Applied ADO.NET: Building Data-Driven Solutions

Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages) ISBN:159059...

Author: Mahesh Chand | David Talbot

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Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2

- Data Components in Visual Studio .NET

Chapter 3

- ADO.NET in Disconnected Environments

Chapter 4

- ADO.NET in Connected Environments

Chapter 5

- Handling ADO.NET Events

Chapter 6

- Integrating XML with ADO.NET

Chapter 7

- Data Binding and Windows Forms Data-Bound Controls

Chapter 8

- Constraints and Data Relations

Chapter 9

- ADO.NET Exception Handling

Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions Back Cover ISBN:1590590732 by Mahesh Chand and David Talbot Applied ADO.NET: Building Data-Driven Solutions provides extensive coverage of ADO.NET technology including Apress © 2003 (928 pages) ADO.NET internals, namespaces, classes, and interfaces. Where most books cover only SQL and OLE DB data This text extensive ADO.NET technology providers, Mahesh Chand andprovides David Talbot covercoverage SQL, OLEofDB, ODBC data providers and the latest additions to including internals, namespaces, and also cover internals of data binding and ADO.NET: Oracle, MySQL, andADO.NET XML .NET data providers. Chandclasses, and Talbot interfaces, takesWindows a comprehensive look atForms XML data binding and data-bound controls. they provide detailed coverage and on both Forms and Web namespaces and classes, and how integrate with a comprehensive look at XML Since XML plays a major role in .NET development, theto authors alsoboth provide ADO.NET. namespaces and classes, and how to integrate both with ADO.NET. Applied ADO.NET: Building Data-Driven Solutions begins with the basics of ASP.NET and data-bound controls. It then delves into internals of data binding and shows how to use DataGrid, DataList, and other data-bound controls Table of Contents in real-world applications. Chand and Talbot also discuss the ASP.NET guest book, database XML Web services, and Applied ADO.NET—Building Data-Driven Solutions even an online bookstore site development and design process. Advanced developers will learn from the coverage Introduction of ADO.NET architecture, related design issues, and how ADO.NET data providers are designed. The authors also show Chapter how1 to -create ADO.NET a Custom BasicsData Provider. Event handling, server side programming, data relations and constraints, Active Directory, messaging, and error handling, and object relational model are other topics Chapter 2 - Data Components in Visual exception Studio .NET covered in detail. Chapter 3 - ADO.NET in Disconnected Environments Chapter 4

- ADO.NET in Connected Environments About the Authors Chapter 5 - Handling ADO.NET Events Mahesh is presentlyXML engaged as a software developer with Kruse. Inc. He has been working with Microsoft ChapterChand 6 - Integrating with ADO.NET database technologies including ODBC, DAO, ADO, and OLE-DB for over 5 years. He has a M.S. degree in Computer Chapter a7 B.S. - Data Binding and and Windows Forms Data-Bound Controls Science, in Mathematics, is also a Microsoft Certified Professional in VC++.In addition to his day job, Mahesh Chapterwrites 8 - Constraints and programs andfor Data C#Relations Corner on C#, VB .NET, ASP .NET and other .NET technologies and help site visitors. Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider David Talbot's background is diverse, ranging from developing license plate recognition technology to television set Chapter 11 - Stored and Views boxes to scalable WebProcedures applications. Currently, David works in the New Business Technologies group at FreeMarkets applying edge .NET technologies to.NET solveData business problems. He has been working with .NET since the early Chapter cutting 12 - Oracle, SQLXML, and Other Providers betas, developing a number of solutions for several start-ups and established companies while working on several Chapter 13 - Developing a Custom Data Provider .NET books and articles. Prior to the development of .NET, David worked primarily on Java, SCO UNIX, Linux, DB2, Chapter 14 -and Developing Database Web Applications using ASP.NET SQL Server, PERL. Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions Applied ADO.NET-Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot Apress MAHESH CHAND AND © 2003 (928 pages)

DAVID TALBOT This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Copyright © 2003 by Mahesh Chand and David Talbot Table of Contents Applied ADO.NET—Building Data-Driven Solutions All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means, Introduction electronic or mechanical, including photocopying, recording, or by any information storage or retrieval Chapter - ADO.NET Basics system,1 without the prior written permission of the copyright owner and the publisher. Chapter 2 - Data Components in Visual Studio .NET ISBN (pbk): 1-59059-073-2 Chapter 3


Printed4and bound in in theConnected United States of America 12345678910 Chapter - ADO.NET Environments Chapter 5


Trademarked names may appear in this book. Rather than use a trademark symbol with every occurrence - Integrating XML with ADO.NET of a trademarked name, we use the names only in an editorial fashion and to the benefit of the trademark Chapter 7 Binding of and Windows Forms Data-Bound owner, with- Data no intention infringement of the trademark.Controls Chapter 6 Chapter 8


Technical Philip Pursglove Chapter 9 -Reviewer: ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

Editorial Directors: Dan Appleman, Gary Cornell, Jason Gilmore, Simon Hayes, Karen Watterson, John Zukowski

Chapter 11 - Stored Procedures and Views

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 -Editor: Developing a Custom Managing Grace Wong Data Provider

Chapter 14 - Developing Database Web Applications using ASP.NET

Project15Manager: Tracy Brown Chapter - Using ADO.NET in XmlCollins Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Development Editor: Philip Pursglove

Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Copy Editor: Kim Wimpsett Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Compositor: Diana Van Winkle,and Van Winkle Design Group Chapter 20 - COM Interoperability ADO.NET Chapter 21 - Messaging

Artist and Cover Designer: Kurt Krames

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix - Relational Indexer:A Ron StraussDatabases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Production Manager: Kari Brooks Appendix C - ADO.NET Frequently Asked Questions Index

Manufacturing Manager: Tom Debolski

List of Figures

List Distributed of Tables to the book trade in the United States by Springer-Verlag New York, Inc., 175 Fifth Avenue,

New NY, 10010 and outside the United States by Springer-Verlag GmbH & Co. KG, Tiergartenstr. List of York, Listings 17,of69112 Heidelberg, Germany. List Sidebars In the United States, phone 1-800-SPRINGER, email , or visit http://www.springer-ny.com. Outside the United States, fax +49 6221 345229, email , or visit http://www.springer.de. For information on translations, please contact Apress directly at 2560 9th Street, Suite 219, Berkeley, CA 94710. Phone 510-549-5930, fax: 510-549-5939, email , or visit http://www.apress.com. The information in this book is distributed on an "as is" basis, without warranty. Although every precaution has been taken in the preparation of this work, neither the author nor Apress shall have any liability to any

person or entity with respect to any loss or damage caused or alleged to be caused directly or indirectly by Applied ADO.NET: Building Data-Driven Solutions the information contained in this work. by Mahesh Chand and David Talbot

ISBN:1590590732

The source codeApress for this©book 2003 (928 is available pages) to readers at http://www.apress.com in the Downloads section. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and and takes look at XML To uncles Banshiinterfaces, Lal and Rajbir Singha comprehensive Malik for their support and guidance. namespaces and classes, and how to integrate both with

-Mahesh Chand ADO.NET. For Nadia whose patience has carried me through this book.

Table of Contents

Applied -DavidADO.NET—Building Talbot Data-Driven Solutions Introduction

About the-Authors ADO.NET Basics

Chapter 1 Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

Mahesh is a Microsoft .NET consultant, an author, and the founder of C# Corner (www.cChapter 18Chand - Object-Relational Mapping in .NET sharpcorner.com), one ofPerformance the leading Considerations online community .NET (C#, VB .NET, and ASP.NET) Chapter 19 - Mapped Objects: and for Data Binding developers. He has a master's degree in computer science and a bachelor's degree in mathematics, and Chapter 20 - COM Interoperability and ADO.NET he is a 21 Microsoft Certified Professional in VC++. Mahesh is also the author of A Programmer's Guide to Chapter - Messaging ADO.NET C# Server (Apress, 2002). Chapter 22 -inSQL and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

David Talbot has worked in a variety of technologies including television set top boxes, license plate recognition, and scalable Web applications. He has written a number of articles concerning .NET technologies and has worked in various capacities on three books. He is currently working as a

development manager in the New Business Technologies group at FreeMarkets in Pittsburgh, Pennsylvania. Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

Apress © 2003 (928 pages) About the Technical Reviewer This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8

- Constraints and Data Relations Philip Pursglove is aException developer with the Willis Group, based in Ipswich, United Kingdom. He has worked Chapter 9 - ADO.NET Handling

with every ofwith Visual onward. Philip was one of the first developers in the UK to gain Chapter 10 -version Working theBasic ODBCfrom .NET3.0 Data Provider the Microsoft Certified Application Developer certification; he also holds the Microsoft Certified Solution Chapter 11 - Stored Procedures and Views

Developer certification in addition to a degree in business information systems. Philip writes for Pinnacle Publishing'sHardcore Visual Basic and SQL Server Professional magazines, and he speaks at user Chapter 13 - Developing a Custom Data Provider group events in the UK. He maintains a Web site at www.philippursglove.com and can be reached Chapter 14 - Developing Database Web Applications using ASP.NET at . Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Chapter 15 - Using ADO.NET in Xml Web Services

Chapter 16 - ASP.NET Server Controls and Data Binding Acknowledgments Chapter 17 - Building Real-World Web Applications

First, I would like to thank Karen Watterson Chapter 18 - Object-Relational Mapping in .NETat Apress. I couldn't even think about finishing this book without her timely comments and motivation. Second, asand always, Chapter 19 -expert Mapped Objects: Performance Considerations Data project Bindingmanager Tracy Brown Collins did a great job of managing the entire project so we could finish it within the time constraints. Without a technical reviewer, a book could never be published. Philip Pursglove did a good job of improving the Chapter 21 - Messaging technical aspect of the book. Thanks also to Kim Wimpsett, the copy editor, and Kari Brooks, the Chapter 22 - SQL Server and ADO.NET: Notes on Performance production manager, for their hard work and for giving the book a professional look. Chapter 20 - COM Interoperability and ADO.NET

Appendix A - Relational Databases: Some Basic Concepts Appendix - Commonly Used SQL Statements -MaheshBChand Appendix C - ADO.NET Frequently Asked Questions

I would like to thank Andy Harris for convincing me to write my first book. Index List of Figures

-David Talbot

List of Tables

List of Listings List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions Introduction ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003developers (928 pages) who want to write desktop or Web-based database applications in This book is for experienced This text provides extensive coverage of ADO.NET technology .NET. This book assumes you have some prior programming knowledge of an object-oriented including ADO.NET internals, namespaces, classes, and programming language such as C++, Java, or Visual Basic; some basic concepts of database interfaces, and takes a comprehensive look at XML programming; and some experience with and previous versions of both Visual Studio (VS). This book also assumes namespaces and classes, how to integrate with you know the basic concepts of .NET and how to install it. ADO.NET.

The following sections briefly introduce this book's chapters. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Chapter 1: "ADO.NET Basics"

Introduction

Chapter 1 - ADO.NET This chapter providesBasics you with a high-level overview of ADO.NET. This chapter covers the basics of Chapter 2 - describes Data Components in Visualover Studio .NET data access technologies, and briefly introduces ADO.NET, its advantages current Chapter ADO.NET 3 -classes ADO.NET and in namespaces. Disconnected Environments It also shows you how to use ADO.NET classes and namespaces to

write simple databaseinapplications using VS .NET (VS .NET). Finally, Microsoft VS .NET provides Chapter 4 - ADO.NET Connected Environments tremendous support ADO.NET for writingEvents database applications in no time using its wizards and utilities. This chapter Chapter 5 - Handling also briefly components and how they fit in the model and work together. Chapter 6 - introduces Integrating ADO.NET XML with ADO.NET Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 MaheshComponents Chand and David Talbot Chapter 2: by "Data in Visual Studio .NET"

Apress © 2003 (928 pages)

The Visual StudioThis .NET .NET)extensive Integratedcoverage Development Environment (IDE) provides design-time text(VS provides of ADO.NET technology support to work with including data components. ADO.NET internals, In thisnamespaces, chapter, you'll classes, learn and how to use these data components in and takes a comprehensive look at XMLThis chapter starts with the Server the VS .NET IDEinterfaces, at design-time to create database applications. namespaces and classes, and how to integrate both with Explorer, a useful tool for database applications. You'll focus on developing database applications quickly ADO.NET. using data components in VS .NET without writing a lot of code. You'll work through a step-by-step tutorial to help you develop and run a project. The chapter also discusses the Connection,DataAdapter, Command, DataSet, and DataView components in more detail. After finishing this chapter, you'll have a Table of Contents good understanding of data components and how to work with them in VS .NET. Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh Chand in andDisconnected David Talbot Chapter 3: by "ADO.NET Environments"


In this chapter, you'll broad view of the coverage ADO.NET and the basic building blocks of This get textaprovides extensive ofarchitecture ADO.NET technology ADO.NET in a disconnected including ADO.NET environment. internals, This namespaces, chapter plays classes, a major and role for later chapters as well. interfaces, takes a look at XML Actually, ADO.NET not onlyand provides a comprehensive way to work with databases, it also allows you to access various namespaces and classes, and how to integrate both with kinds of data sources and even in-memory representations of data. You'll learn how to write database ADO.NET. applications without using a database. You'll also explore the System.Data and System.Data.Common namespace classes. Some of the common data objects covered in this chapter are DataTable, DataColumn, DataRow, and DataSet. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh Chand in andConnected David Talbot Chapter 4: by "ADO.NET Environments"


This chapter examines ADO.NET in a connected environment, This text provides functionality extensive coverage of ADO.NET technology which means you won't be storing data in memory. including You'll ADO.NET be reading internals, andnamespaces, storing dataclasses, in data sources. and You access data from a data takes comprehensive source and save interfaces, data back and to the dataa source with thelook helpatofXML a bridge between the application and the namespaces and classes, and how to integrate both with data source; in ADO.NET this bridge is a data provider. ADO.NET provides many data providers for ADO.NET. working with different data sources to make data access fast, reliable, and easy to use. Each data provider has data components (classes) that let you connect to a data source and read, write, add, delete, and update data. This chapter examines these components and shows how to use Windows data-bound Table of Contents controls to bind data with Data-Driven ADO.NET components. Applied ADO.NET—Building Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions Mahesh ChandADO.NET and David Talbot Chapter 5: by "Handling Events"

ISBN:1590590732


Events are usefulThis for notifying you extensive when some action happens to technology an object. An event can have a method text provides coverage of ADO.NET associated with it.including Not too ADO.NET many books internals, cover namespaces, the ADO.NET classes, eventsand in details. This chapter shows you how interfaces, and takes objects. a comprehensive at XML you can handle events for ADO.NET It coverslook almost every ADO.NET data component event and and classes, and how to integrate both with how to use them namespaces in your applications. ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh Chand and David with Talbot ADO.NET" Chapter 6: by "Integrating XML


This chapter begins introduction of the classes the .NET Framework Library to work Thiswith textthe provides extensive coverage of provided ADO.NET by technology with Extensible Markup including Language ADO.NET(XML) internals, documents. namespaces, Thisclasses, chapterand discusses how to read from and write to and takes a comprehensive look at After XML that it discusses how to navigate XML documents interfaces, using the .NET Framework Library classes. namespaces and classes, and how to integrate both with through XML documents. The chapter also discusses XML transformations. In addition, this chapter covers ADO.NET. the relationship between ADO.NET and XML and shows how to mix them up and use rich ADO.NET database components to display and manipulate XML data. Finally, this chapter covers the XPathNavigator class, which navigates XML documents. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 MaheshBinding Chand and David Chapter 7: by "Data andTalbot Windows Forms Data-Bound Apress © 2003 (928 pages) Controls" This text provides extensive coverage of ADO.NET technology

including ADO.NET internals, namespaces, classes, and

Data-bound controls are not only ease to use, but they also provide many built-in features that interfaces, and takes a comprehensive look at XML programmers willnamespaces find useful. and Thisclasses, chapterand discusses the basics of data how to integrate both with binding and data-bound controls, as well as how toADO.NET. develop interactive Graphical User Interface (GUI) database applications using these controls in minimal time and with minimal effort. This chapter covers how to use Windows controls such as theTextBox,Button,Label,CheckBox,ComboBox,ListBox, and DataGrid controls in the dataTable of Contents binding process and how to write your custom data-bound applications to navigate through the records of Applied Data-Driven Solutions a data ADO.NET—Building source. In this chapter, you'll learn some data-binding techniques that are hard to find in other Introduction ADO.NET books. Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh Chand andand David Data Talbot Relations" Chapter 8: by "Constraints


This chapter discusses constraints and data coverage relations of in ADO.NET detail. First, this chapter starts with a discussion of This text provides extensive technology constraints and how including ADO.NET ADO.NET constraint internals, objects namespaces, maintainclasses, data integrity. and The second part of this chapter interfaces, and takes a comprehensive look at XML discusses data relations. namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh Chand Exception and David Talbot Handling" Chapter 9: by "ADO.NET


Exception and error is oneextensive of the most important parts oftechnology writing reliable and error-prone Thishandling text provides coverage of ADO.NET applications. If you including come from ADO.NET a C++ internals, background, namespaces, you're probably classes, and familiar with different exceptional and takes a comprehensive look at XMLexceptional handling, and Microsoft handling methodsinterfaces, such as C++ exceptional handling, structured namespaces and classes, and how to integrate both with Foundation Classes (MFC) exceptions. If you come from a Visual Basic background, you're probably ADO.NET. familiar with the On Error statement. Besides the exception handling in previous versions of VC++ and Visual Basic, .NET implements exceptions in a different way, and all .NET-supported languages (C# and VB .NET) share the same mechanism. Now Visual Basic developers can enjoy the same rich exception Table of Contents handling C++ developersData-Driven have enjoyed. Discussing .NET exception handling is beyond the scope of this Applied ADO.NET—Building Solutions book; this chapter concentrates on ADO.NET exception handling classes. Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh Chand and David Talbot Chapter 10:by"Working with the ODBC .NET Data Provider"


This chapter discusses theprovides ODBC extensive .NET datacoverage providerofand how totechnology work with various data sources such as This text ADO.NET Access, MySQL, including Excel, and ADO.NET text using internals, the ODBC namespaces, data provider. classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh Chand and David Talbot and Views" Chapter 11:by"Stored Procedures


Stored procedures and views are another important of database programming. This chapter This text provides extensive coverageaspect of ADO.NET technology discusses how you including can take ADO.NET advantage internals, of VSnamespaces, .NET tools to classes, work with and these objects. interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions Mahesh Chand and David Talbot Chapter 12:by"Oracle, SQLXML, and OtherISBN:1590590732 .NET Data Providers" Apress © 2003 (928 pages)

In this chapter, you'll more data providers—specifically, Oracle and SQLXML. In previous This see text some provides extensive coverage of ADO.NET technology chapters, you learned including howADO.NET to work with internals, other namespaces, data providers, classes, so working and with the rest of them is just a and takes a comprehensive look at XML piece of cake. Allinterfaces, data providers implement a similar class hierarchy model with only a few changes. This namespaces and classes, and how to integrate both with chapter concentrates how to work with Oracle databases and how to access SQL Server using SQLXML. ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions Mahesh Chand and David Talbot Chapter 13:by"Developing a Custom Data ISBN:1590590732 Provider" Apress © 2003 (928 pages)

ADO.NET is an extensible architecture that allows anyone, not just Microsoft, to create data providers for This text provides extensive coverage of ADO.NET technology virtually any type including of data source. ADO.NET This internals, chapternamespaces, covers how classes, to createand a data provider for pipe-delimited data interfaces, takesespecially a comprehensive at XMLThis data provider plugs in to the files, which is a common fileand format, for Unixlook systems. namespaces and classes, and how to integrate both with ADO.NET architecture and provides all of the things you would expect from a data provider, including the ADO.NET. ability to fill a DataSet and bind it to any GUI object. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


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Chapter 7


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Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh Chand and David Talbot Chapter 14:by"Developing Database Applications Using ASP.NET"


As the programming moves extensive toward thecoverage Internet of these days,technology it's becoming important for developers This world text provides ADO.NET to be able to create including Web applications ADO.NET internals, and Web namespaces, services. The classes, Microsoft and .NET Framework enables you to interfaces, andreliable takes a and comprehensive look at XML develop, maintain, and deploy high-performance Web applications and Web services. This namespaces and classes, and how to integrate both with chapter starts with an overview of ASP.NET and how to install it, and it then shows how to develop a ADO.NET. simple Web application using VS .NET. Finally, it discusses Web Forms controls and how to use them. The Web Form's DataGrid control is a useful control to develop Web-based database applications. You can of bind a DataSet to the DataGrid control as you did for the Windows Form's DataGrid control. This Table Contents chapter discusses how toData-Driven fill data to aSolutions DataGrid and how to develop powerful Web-based database Applied ADO.NET—Building applications using the DataGrid control. It also discusses how to enable paging in a DataGrid control. Introduction Finally,1it shows you how to develop an ASP.NET guest book for your Web site using ASP.NET. Chapter - ADO.NET Basics Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh Chand and David Talbot Chapter 15:by"Using ADO.NET in XML Web Services"


Web services provide a way to run extensive a service coverage on the Web and access its methods using standard protocols, This text provides of ADO.NET technology including Simple including Object Access ADO.NET Protocol internals, (SOAP), namespaces, XML, Web classes, Service and Description Language (WSDL), and interfaces, takes Technically, a comprehensive look at XMLis nothing more than an application that Hypertext Transfer Protocoland (HTTP). a Web service namespaces and classes, and how to integrate both with exposes its interface over the Web to a client who wants to access the service's abilities. The uses of a ADO.NET. Web service include validating credit cards, searching for data in a database, inserting an order into a shopping cart, and updating a guest list. The sky is the limit on what you can have your Web service do. In the past, JavaBeans, Component Object Model (COM) components, and other, nonstandard service Table of Contents components handled these services, Solutions which required specialized formats or extra, specialized components Applied ADO.NET—Building Data-Driven to exchange data with the client. But Web services under .NET run by invoking methods in the service Introduction directly1through HTTPBasics or SOAP, so someone wanting to run your Web service from their computer can Chapter - ADO.NET simply send an HTTP call to your service, passing Chapter 2 - Data Components in Visual Studio .NET the parameters in a standard Uniform Resource Locator (URL). This chapter shows you how to use ADO.NET in XML Web services. Chapter 3 - ADO.NET in Disconnected Environments Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh Chand and David Talbot Chapter 16:by"ASP.NET Server Controls and Data Binding"


Chapter 14 discussed some of theextensive basics of coverage data binding in Web Forms and ASP.NET data-bound This text provides of ADO.NET technology controls. You alsoincluding saw how ADO.NET to use data-bound internals, namespaces, controls in classes, Web applications. and Chapter 15 discussed how to interfaces, and takes comprehensive lookfunctionality at XML develop data-driven Web services anda how to access the implemented in a Web service from namespaces and classes, and how to integrate both with Web Forms applications. This chapter extends the information in Chapter 14 and concentrates on the ADO.NET. more practical aspect of data binding and Web Forms data-bound controls. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

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Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh Chand Real-World and David Talbot Web Applications" Chapter 17:by"Building


Chapter 14 discussed the provides basics ofextensive ASP.NET and how write data-driven This text coverage ofto ADO.NET technologyWeb applications using ASP.NET and ADO.NET. including ADO.NET Chapter 16 internals, discussed namespaces, data binding classes, in ASP.NET and and ASP.NET server controls interfaces, andtotakes a comprehensive look at XML and how to use these controls develop data-bound Web applications. This chapter uses the functionality namespaces and classes, and how to integrate both with discussed in those chapters. You'll see how you can write a real-world online job board where candidates ADO.NET. can post their resumes, recruiters can post their jobs, recruiters can browse the available resumes, and job hunters can browse and apply for the available jobs online. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

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Applied ADO.NET: Building Data-Driven Solutions Mahesh Chand and David Talbot Chapter 18:by"Object-Relational Mapping ISBN:1590590732 in .NET" Apress © 2003 (928 pages)

Object-relational This mapping is a commonly desired software architecture element on any platform because text provides extensive coverage of ADO.NET technology of the encapsulation including and modeling ADO.NET of internals, data behavior namespaces, from aclasses, relational anddatabase into an object. Although and takes a(XSD) comprehensive look at XML from data, these objects are not easily you can use XMLinterfaces, Schema Document files to create objects namespaces and classes, and how to integrate both with extensible in regard to modeling data behavior. The technique discussed in this chapter extends the ADO.NET. concept provided by Duwamish7 (a demo application from Microsoft) to create custom-built mapped objects. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

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Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh ChandObjects: and David Talbot Chapter 19:by"Mapped Performance Considerations and Apress © 2003 (928 pages) Data Binding" This text provides extensive coverage of ADO.NET technology

including ADO.NET internals, namespaces, classes, and

Building on the object-relational concepts discussed in Chapter 18, this chapter deals with the common interfaces, and takes a comprehensive look at XML problems encountered in a mapped system, performance considerations and how to use data namespaces and classes, andincluding how to integrate both with binding. Data binding ADO.NET. is the preferred way to work with data in .NET, but you'll need to alter your code slightly when using mapped objects. In addition, performance is always a consideration in creating a scalable system, but often many of the things that improve performance can lead to an unmaintainable Table of Contents system design. In the performance part of the chapter, it discusses common performance problems such Applied ADO.NET—Building Data-Driven Solutions as managing large tree structures and balancing the ease of use that lazy loading can provide vs. Introduction reducing round trips to the database. Chapter 1

- ADO.NET Basics

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Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh Chand and David Talbot Chapter 20:by"COM Interoperability with ADO.NET"


COM has been around forprovides many years and iscoverage used byofmany Windows applications. Eventually .NET This text extensive ADO.NET technology platform will replace including COM,ADO.NET but until internals, then you namespaces, may need to classes, developand COM components from .NET and and code, takes aorcomprehensive at XML access them frominterfaces, unmanaged you may wantlook to use COM components in .NET applications. namespaces and classes, and how to integrate both with COM interoperability (also referred to as COM Interop) enables you to use existing COM components in ADO.NET. .NET applications or use .NET components in unmanaged code. This chapter shows you how to use ADO and other COM-based data access technologies through COM Interop in your .NET applications. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


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Applied ADO.NET: Building Data-Driven Solutions Mahesh Chand and David Talbot Chapter 21:by"Messaging"

ISBN:1590590732


A messaging service one of the most effective and popular mediums to communicate between two This is text provides extensive coverage of ADO.NET technology machines. It doesn't including matterADO.NET if you'reinternals, a high-tech namespaces, developer,classes, a stockbroker, and a high-school student, or a and takes comprehensive look at XML businessperson. interfaces, In some means, youaprobably use messaging services. Some of the common messaging namespaces and classes, and how to integrate both with services are electronic mail (email), instant messenger services, text messaging via phones, or messaging ADO.NET. used in complex distributed applications. This chapter covers messaging and its related functionality defined in the .NET Framework Class Library, as well as how to use it in your applications. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


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Applied ADO.NET: Building Data-Driven Solutions Mahesh Chand and David Chapter 22:by"SQL Server andTalbot ADO.NET: ISBN:1590590732 Notes on Performance" Apress © 2003 (928 pages)

Database performance has alwaysextensive been something black arttechnology consisting largely of obscure tricks. This text provides coverageofofaADO.NET Although there's no including single ADO.NET trick that internals, will makenamespaces, your application classes, scale, andthere are several tricks that can help interfaces, and takes aproblems. comprehensive look at XML you identify and address performance This chapter covers those tricks. It also discusses some namespaces and classes, and how to integrate both with best practices to make sure you get most out of your code. ADO.NET.


- ADO.NET Basics

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Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by "Relational Mahesh Chand andDatabases:Some David Talbot Appendix A: Basic Concepts"


Appendix A covers some the basics of databases, as locking, cursors, and normalization. This text of provides extensive coverage such of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


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Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot Appendix B: "Commonly Used SQL Statements"


SQL is a vital partThis of database programming. Appendix is a quick reference to SQL statements and text provides extensive coverage of B ADO.NET technology shows you how toincluding write various ADO.NET SQLinternals, statements. namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


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Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot Appendix C: "ADO.NET Frequently Asked Questions"


This appendix answers some of theextensive commonly asked of questions to ADO.NET. Most of these This text provides coverage ADO.NETrelated technology questions were originally on the discussion forums at C# Corner includingasked ADO.NET internals, namespaces, classes, and (www.c-sharpcorner.com) or interfaces, and takes a comprehensive look at XML other newsgroups. namespaces and classes, and how to integrate both with ADO.NET.


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ADO.NET: Building Data-Driven Solutions Chapter Applied 1: ADO.NET Basics ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

Highlights This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

Activex data objects interfaces, for the and .NETtakes Framework a comprehensive (ADO.NET) lookisatthe XML latest database access technology from namespaces andissues classes, and how to integrate withtechnologies and provides the Microsoft. ADO.NET addresses with previous databaseboth access ADO.NET. foundation for future scalability. Although ADO.NET stands for Active Data Objects .NET, it's perhaps misnamed because unlike ActiveX Data Objects (ADO), ADO.NET isn't an ActiveX/Component Object Model technology. As the business world is moving onto the Internet, one of the main goals of Table of (COM) Contents ADO.NET is allow developers to writeSolutions high-performance, reliable, and scalable database applications over Applied ADO.NET—Building Data-Driven the Internet. ADO.NET uses .NET Common Language Runtime (CLR) services to manage the library, and Introduction it utilizes Extensible Markup Language (XML) to cache the data and exchange data among applications Chapter 1 - ADO.NET Basics over the Internet as well as intranets. Chapter 2


Chapter 3 inthis ADO.NET in Disconnected Environments Our goal chapter is simply to provide you with a high-level overview of ADO.NET. In it, we provide Chapter 4 -ofADO.NET in Connected Environments the basics ADO.NET, describe its advantages over current data access technologies, and briefly Chapter 5 ADO.NET - Handling ADO.NET Events introduce classes and namespaces as well as show how to use them to write simple database Chapter applications 6 - Integrating using Microsoft XML with Visual ADO.NET Studio .NET (VS .NET). VS .NET provides tremendous support for

writing 7database applications in no time, using its wizardsControls and utilities. (Chapter 2 covers VS .NET and Chapter - Data Binding and Windows Forms Data-Bound ADO.NET In this we also briefly describe the ADO.NET components and how they fit in Chapter 8 -support.) Constraints and chapter, Data Relations the model work together. Chapter 9 -and ADO.NET ExceptionChapters Handling 3 and 4 discuss these components in more detail. Specifically, in Chapter coverwith the ADO.NET object model in disconnected environments, and in Chapter 4, we Chapter 103,- we Working the ODBC .NET Data Provider cover ADO.NET in Procedures connected and environments. Chapter 11 - Stored Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Note The .NET Base Class Library is also called the .NET Runtime Library or the .NET Framework

Chapter 13 Class - Developing Library.a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

ADO.NET: Building Data-Driven Solutions Overview ofApplied Microsoft Data Access Technologies by Mahesh Chand and David Talbot

ISBN:1590590732

To understand the importance of ADO.NET, it's useful to take a quick look at existing Microsoft database Apress © 2003 (928 pages) access technologies before ADO.NET. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

Since the first release of Open Connectivity (ODBC) to access databases for Windows interfaces, andDatabase takes a comprehensive look at XML namespaces and introducing classes, andand howimproving to integrate both applications, Microsoft has been ways towith make database programmers' lives ADO.NET. easier. In this series of database technologies, it introduced many new technologies and improved existing technologies. Each of these technologies has its own pros and cons. Some of the technologies are specific to a particular kind of data source, and some of them are common to all kinds of data sources. Table of Contents Together these technologies are called Microsoft Data Access Technologies or Microsoft Data Access Applied ADO.NET—Building Data-Driven Solutions Components (MDAC). These technologies include the following: Introduction

Chapter 1 - ADO.NET Basics ODBC Chapter 2

- Data Components in Visual Studio .NET Data Objects (DAO) Chapter 3 Access - ADO.NET in Disconnected Environments Chapter 4


Chapter 5


Microsoft Foundation Classes (MFC) ODBC and DAO classes

Chapter 6 - Integrating XML(RDO) with ADO.NET Remote Data Objects Chapter 7


Object and and Embedding Database (OLE DB) Chapter 8 - Linking Constraints Data Relations Chapter 9

ADO


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

ODBC

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

ODBC was the first formal database access technology introduced by Microsoft. ODBC provides a lowlevel C/C++ Application Programming Interface (API) to retrieve data from relational databases such as Chapter 15 - Using ADO.NET in Xml Services SQL Server, Access, or Oracle byWeb using ODBC drivers and ODBC Administration. With the help of ODBC Chapter 16 ASP.NET Server Controls and Datayou Binding drivers and the ODBC Administration utility, can connect to any ODBC-compliant data source using Chapter 17 Building Real-World Web Applications the ODBC API. However, ODBC is relational in nature, so it's difficult to use ODBC to communicate with Chapter 18 - Object-Relational Mapping in .NET nonrelational data sources such as object databases, network directory services, email stores, and so on. Chapter 14 - Developing Database Web Applications using ASP.NET

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Figure 20 1-1-shows ODBC connectivity to a database through an ODBC driver and ODBC Administration, Chapter COM Interoperability and ADO.NET also called ODBC driver manager. Chapter 21 - the Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 1-1: ODBC architecture Using ODBC functions isn't a fun way of programming for high-level programmers. ODBC is a hierarchical model, which means you have to create environment and database objects before creating a recordset object with which you can start accessing the data. Other problems with ODBC are multiple connections and multiple data sources. An ODBC connection doesn't allow you to connect to two data sources using the same connection. You need to use two separate connection objects to do so. Being non-objectoriented in nature and having poor memory management are other drawbacks of ODBC. For the History Buffs: How ODBC Came to Be [1]

In early 1988,Applied Microsoft's Applications Group realized it Solutions had a problem. Microsoft had a whole slew of ADO.NET: Building Data-Driven applications that needed to share data. Enter Kyle Geiger. Geiger, fresh from eight years of ISBN:1590590732 by Mahesh Chand and David Talbot experience atApress Wang©Laboratories-primarily in PC databases-recalls that he was given this sort of ill2003 (928 pages) defined problem and told to go "think about it for awhile." Well, Geiger This text provides extensive coverage of ADO.NET technologythought about it for awhile and restated the problem one of internals, deliveringnamespaces, data "from anywhere" into Microsoft applications, producing including as ADO.NET classes, and interfaces, and takes a comprehensive look at XML a first specification by spring 1988. namespaces and classes, and how to integrate both with ADO.NET. By spring 1989, the emerging ODBC specification had gone through several drafts. Geiger and members of Microsoft's Applications and Systems groups wrestled with how much reliance they should put on the just-inherited Sybase DB-Library API. Concurrently, Geiger heard about what was Table of Contents eventually to become the SQL Access Group (SAG). Then came three grueling years of consensus Applied ADO.NET—Building Data-Driven Solutions building as a member of the SAG. The culmination of the first phase was the March 1992 ODBC Introduction Developers Conference where the ODBC 1.0 Software Development Kit (SDK) was demonstrated Chapter 1 - ADO.NET Basics and distributed. Chapter 2


Chapter The 3 design - ADO.NET goalsinofDisconnected ODBC wereEnvironments to provide location, a Database Management System (DBMS), and

particular ODBC in driver transparency; to provide SQL as a language for universal data access, even to Chapter 4 - ADO.NET Connected Environments non-SQL data sources; to Events leverage existing and evolving standards; and to provide tools for easy Chapter 5 - Handling ADO.NET ODBC and administration. Chapter 6 - setup Integrating XML with ADO.NET Chapter 7


Although ODBC was designed as a Windows-specific API, because it was built on top of the SAG's Chapter 8 - Constraints and Data Relations Call Level Interface specification, the potential for cross-platform, ODBC-compliant APIs was always Chapter 9 - ADO.NET Exception Handling present. In fact, in 1994, ODBC links to both the Unix and Macintosh worlds (via Apple Data Access Chapter 10 - Working withbegan the ODBC .NET Data Provider Language, or DAL) to appear. Chapter 11 - Stored Procedures and Views

Meanwhile, Microsoft revised the ODBC specification Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers and introduced it as the ODBC 2.0 SDK. The main between ODBC and ODBC 2.0 was new 32-bit support and enhanced functionality Chapter 13 difference - Developing a Custom Data1.0 Provider for 14 the- so-called "navigational" model. The latter Chapter Developing Database Web Applications usingessentially ASP.NET maps SQL functionality to non-SQL databases and data sources xBASE and Paradox. Chapter 15 - Using ADO.NET in Xml including Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

DAO

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

DAO is a set of COM interfaces for accessing databases; it uses the Microsoft Jet database engine to connect. DAO is best suited for accessing desktop databases including Access, FoxPro, and SQL Server Chapter 22 - SQL Server and ADO.NET: Notes on Performance because it can directly connect to these databases through the Jet database engine. Figure 1-2 shows the Appendix A - Relational Databases: Some Basic Concepts connectivity between a client application, an Access database, and ODBC data sources using DAO. Chapter 21 - Messaging

Appendix B - Commonly Used SQL Statements

Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 1-2: DAO model DAO is easier to use than the ODBC API, but it doesn't provide the degree of low-level control and flexibility afforded by the ODBC API. Therefore, you could classify DAO as a high-level database interface. To access non-Access databases, DAO uses ODBC internally, which adds one more layer of API to access ODBC data sources. This degrades the performance of DAO while accessing ODBC data sources.

MFC ODBCApplied and DAO Classes ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

MFC is a set of C++ classes that provides DAO and ODBC classes to access databases that use DAO Apress © 2003 (928 pages) and ODBC. These classes provide a high-level programming model for Visual C++ developers working This text provides extensive coverage of ADO.NET technology with DAO and ODBC. These classes are a nice wrapper around DAO and ODBC APIs. A drawback of including ADO.NET internals, namespaces, classes, and these classes is that they aren't flexible enough. Also, they slow in performance because of too many interfaces, and takes a comprehensive look are at XML layers. namespaces and classes, and how to integrate both with ADO.NET.

RDO Table of Contents

RDO isADO.NET—Building an object interface for ODBC Solutions that provides an OLE layer on the top of the ODBC API. The main Applied Data-Driven advantage of RDO is that it gives developers an object interface for ODBC developers, but the disadvantage is that it's slow in performance because of too many layers. It also suffers the ODBC Chapter 1 - ADO.NET Basics limitation of not being well suited for nonrelational data sources. Introduction Chapter 2


Chapter 3


OLE DB - ADO.NET in Connected Environments

Chapter 4 Chapter 5


OLE DB was designed to access all kinds of data including relational, nonrelational, text data, graphical - Integrating XML with ADO.NET data, and directory services. OLE DB components consist of data providers, which expose their data; data Chapter 7 - Data Binding and Windows Forms Data-Bound Controls consumers, which use data; and service components, which process and transport data (for example, Chapter 8 - Constraints and Data Relations query processors and cursor engines). OLE DB is a low-level programming model and provides the most Chapter 9 and - ADO.NET Exception flexibility control over data.Handling Figure 1-3 shows the OLE DB model. Chapter 6

Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - 1-3: COM OLE Interoperability Figure DB model and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

As you can see from Figure 1-3, a client application accesses a database through an OLE DB provider and consumers. You must have an OLE DB provider installed to use OLE DB in your application; database Appendix B - Commonly Used SQL Statements venders provide this. Appendix A - Relational Databases: Some Basic Concepts Appendix C - ADO.NET Frequently Asked Questions Index

ADO

List of Figures List of Tables

ActiveX Data Objects (ADO) is a set of ActiveX components that provide object-based programmatic access to OLE DB. ADO is a COM wrapper around OLE DB libraries. ADO is much simpler to use than List of Sidebars OLE DB; you can classify it as a high-level database interface. List of Listings

In comparison to other data access technologies, ADO provides many benefits. ADO is easy to program and, with a few exceptions, is faster than ODBC and DAO. ADO also provides more flexibility and control over data. You don't have to go through a hierarchy of objects to access data as you do in DAO or ODBC. ADO (OLE DB) is a set of COM interfaces. This means ADO provides a binary standard to access any kind of data source. You can use ADO with any language that supports COM, such as Visual Basic (VB) or C++. ADO also supports XML data access with the help of Microsoft XML (MSXML).

ADO.NET

ADO.NET is an evolution of ADO. The ADO.NET and XML .NET APIs construct a uniform model to work Applied ADO.NET: Building Data-Driven Solutions with XML data from any type of data store. The ADO.NET API is managed code, which means you get all ISBN:1590590732 Mahesh Chand and David Talbot the advantages ofby.NET, including automatic memory management and garbage collection. Unlike DAO Apress © 2003 (928 pages) or ODBC, though, you don't have to install new libraries to make an ADO.NET program work if you are This text provides extensive coverage ADO.NET technology already running .NET applications on a machine. We of discuss ADO.NET in more detail in the following including ADO.NET internals, namespaces, classes, and section. interfaces, and takes a comprehensive look at XML [1]Karen Watterson, "ODBC," and Microsoft SQL July 1992. namespaces classes, andServer how toConnection, integrate both with ADO.NET.


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Applied ADO.NET: Building Data-Driven Solutions What Is ADO.NET? by Mahesh Chand and David Talbot

ISBN:1590590732

ADO.NET is a new database technology created by Microsoft; its .NET Framework can access any Apress © 2003 access (928 pages) kind of data source. It's a collection of object-oriented classes thattechnology provides a rich set of data components This text provides extensive coverage of ADO.NET to create high-performance, reliable, and scalable database applications for client-server applications as including ADO.NET internals, namespaces, classes, and and takes comprehensive look at XML well as distributedinterfaces, environments over athe Internet and intranets. namespaces and classes, and how to integrate both with ADO.NET. In the ADO.NET model—unlike ADO (in connected state) and previous data access

technologies—applications are connected to the data sources only when they are reading or updating the data. After that, the connection closes. This is important because in client-server or distributed Table of Contents applications, having connection resources open all the time is one of the most resource-consuming parts. Applied ADO.NET—Building Data-Driven Solutions You don't have to connect to a data source all the time; the only time you need to connect to a data source Introduction is when you are reading and writing final changes to a data source. Chapter 1

- ADO.NET Basics

Chapter - Data Components in Visual Studio .NET The old2 approach of having connections open all the time is problematic when considering the number of Chapter ADO.NET Disconnected Environments clients 3that- access theinsame data source simultaneously. In larger systems, Microsoft Transaction Server Chapter (MTS)/COM+ 4 - ADO.NET was often in Connected used to pool Environments ADO connections to address some of this resource consumption;

however, more optimal paradigm for large systems without needing to utilize Chapter 5 ADO.NET - Handling provides ADO.NET aEvents MTS/COM+ enterprise XML services—unless, Chapter 6 - Integrating with ADO.NET of course, you need to take advantage of such advanced techniques a three-phase commit. Forms Data-Bound Controls Chapter 7 - as Data Binding and Windows Chapter 8


ADO.NET uses Structured Query Language (SQL) queries and stored procedures to read, write, update, ADO.NET Exception Handling and deletedata from a data source. You use SQL queries through the ADO.NET Command object, which Chapter 10 withof the ODBC .NET Data Provider objects. After that connection is closed with the data returns dataWorking in the form DataReader or DataSet Chapter 11 Stored Procedures and Views source, you use DataSet objects to work with the data and connect to the data source again when you Chapter - Oracle, and Other .NET Data Providers need to12 update the SQLXML, data source. Chapter 9

Chapter 13 - Developing a Custom Data Provider

Note queries Database are also called SQL statements. See Appendix B for some SQL query examples. Chapter 14 SQL - Developing Web Applications using ASP.NET Chapter 11 for details on stored procedures. Chapter 15 See - Using ADO.NET in more Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

ADataSet is a collection of DataTable objects and the relationships among them. It works as a container that stores returned data from a database in cached form. You can fill a DataSet with the data Chapter 18 - Object-Relational Mapping in .NET retrieved from multiple tables of a database. Once you have a DataSet (which is disconnected data, stored Chapter - Mapped Objects: Performance Considerations Binding on your19 local machine), you treat the DataSet as your and dataData source and work with it. You call the Update Chapter COM Interoperability and ADO.NET method20to-make DataSet changes final to the actual database. You can even read and update a Chapter 21 -from Messaging DataSet different data sources. Chapter 17 - Building Real-World Web Applications

Chapter 22 - SQL Server and ADO.NET: Notes on Performance

You access a data source and fillSome a DataSet via data providers. The .NET Framework provides three Appendix A - Relational Databases: Basic Concepts differentBtypes of data providers ship with the version 1.0 of Visual Studio .NET: Sql, OleDb, and Odbc. Appendix - Commonly Used SQL that Statements MicrosoftC and third parties have Asked also developed Appendix - ADO.NET Frequently Questions data providers for the Oracle database. Some companies also have developed data providers for MySql and other databases. You use a DataAdapter object of a data provider and call its Fill method to fill a DataSet.

Index

List of Figures

List of plays Tablesa major role in ADO.NET. The ADO.NET model utilizes XML to store the data in cache and XML List of Listings transfer the data among applications. DataSets use XML schemas to store and transfer data among List of SidebarsYou can even use this XML file from other applications without interacting with the actual applications.

DataSet. Because XML is an industry standard, data can be used among all kinds of applications and components; because of its text-based nature, data can be transferred via many protocols, such as Hypertext Transfer Protocol (HTTP). We discuss XML and ADO.NET integration and how you can take advantage of XML support in ADO.NET applications in Chapter 6.

Applied ADO.NET: Building Data-Driven Solutions Why ADO.NET Was Designed by Mahesh Chand and David Talbot

ISBN:1590590732

As mentioned, each previous access technology has its own pros and cons. Some of them were Apress © 2003 data (928 pages) designed specifically for a particular type of data source, some of technology them aren't easy to program for This text provides extensive coverage of ADO.NET developers, and some of them don't have good enough performance. including ADO.NET internals, namespaces, classes, and For example, the ODBC API is a set interfaces, and takes a comprehensive look at XMLapplications using ODBC is a timeof C functions. It has no object-oriented support. So, developing namespaces and classes, andproblem how to integrate bothiswith consuming process for developers. Another with ODBC its relational nature. The ODBC API is ADO.NET. limited to relational databases, and it's difficult to use ODBC with nonrelational data sources such as network directories, email stores, ISAM data, object data, and so on. Table of Contents

DAO is an object model but was specifically designed to work with the Microsoft Jet database engine. The MFC ODBC and DAO classes are one more wrapper for ODBC and DAO APIs. Because of this extra Introduction wrapper, these classes aren't up to the mark performance-wise and still have some of the same limitations Chapter 1 - ADO.NET Basics as ODBC and DAO. Applied ADO.NET—Building Data-Driven Solutions

Chapter 2


Chapter 3 is- aADO.NET Disconnected OLE-DB solution in that works with Environments any kind of data source using OLE-DB providers and consumers; Chapter however, 4 writing - ADO.NET OLE-DB in Connected applications Environments is time consuming, and it's hard for developers to program them.

Moreover, a flat model. That means you could directly connect to a table without going through Chapter 5 -OLE-DB HandlingisADO.NET Events hierarchical objects of connections and databases. Because of the lower-level programming model of the Chapter 6 - Integrating XML with ADO.NET OLE API, OLE-DB API isn't easy toForms program for non-OLE programmers. Chapter 7 the - Data Binding and Windows Data-Bound Controls Chapter 8


To overcome this problem, Microsoft introduced ADO. ADO is a high-level programming model, and it was - ADO.NET Exception Handling the best data access technology at that point. It's a nice COM wrapper for the OLE-DB API, and it suits Chapter 10 - Working with the ODBC .NET Data Provider most developers. The first major drawback of ADO is that it's a COM-based model. Writing COM-based Chapter 11 - Stored Procedures Views one of the most difficult models of programming and a pain for applications and using them isand probably Chapter 12 Oracle, SQLXML, and Other .NET Data Providers non-COM developers. The second drawback is the limited support for XML. You can read XML documents Chapter - Developing a Custom Data through13ADO, but documents have to Provider have a certain format, which negates many of the benefits of XML. Chapter 9


Keeping these ADO.NET problemsininXml mind, Microsoft Chapter 15all - Using Web Serviceswrote a set of new object-oriented classes: ADO.NET. ADO.NET itsServer programming from its predecessor ADO, so ADO programmers will see Chapter 16 -inherits ASP.NET Controls model and Data Binding something between these two APIs. As such, it will also take less time to jump from ADO to Chapter 17 -common Building Real-World Web Applications

ADO.NET. ADO.NET classes are based on the ADO model and have some objects in common, such as Connection and Command. However, DataSets replace recordsets in ADO.NET. These classes are Chapter 19 - Mapped Objects: Performance Considerations and Data Binding easy to use and have solutions for all the problems mentioned. Chapter 18 - Object-Relational Mapping in .NET

Chapter 20 - COM Interoperability and ADO.NET

Chapter - Messaging In brief,21 ADO.NET was designed to meet today's programming needs, including disconnected data, tight Chapter 22 SQL XML, Server anda ADO.NET: Notes on integration-with and common model to Performance work with all kinds of data sources. Welcome to the Appendix A -world. Relational Databases: Some Basic Concepts ADO.NET Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

ADO.NET: Building Data-Driven Solutions AdvantagesApplied of ADO.NET by Mahesh Chand and David Talbot

ISBN:1590590732

ADO.NET offers Apress several©advantages over previous Microsoft data access technologies, including ADO. 2003 (928 pages) The following sections outline these advantages. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Single Object-Oriented API

As discussed earlier, with the many available data access methods, sometimes developers are confused about which technology to use. For example, to work with Microsoft Access databases, you can use Table of Contents ODBC, DAO, OLE-DB, ADO, DAO, or ODBC MFC classes. Applied ADO.NET—Building Data-Driven Solutions

Which one would you choose? It all depends on your requirements. Another problem with these Introduction technologies is installing the right version. For example, ODBC and ADO have different versions of DLLs, Chapter 1 - ADO.NET Basics and some -ofData these versions aren't backward or forward compatible. So, if a user is running some Components in Visual Studio .NET programs that require ODBC 3.0 and your application uses ODBC 3.5, then the user will have to install Chapter 3 - ADO.NET in Disconnected Environments ODBC 3.5 to run your application. However, the users' programs that are based on ODBC 3.0 may not Chapter 4 - ADO.NET in Connected Environments work properly after installing ODBC 3.5. Having multiple DLL versions is a well-known problem, termed Chapter 5 - Handling ADO.NET Events DLL hell. Chapter 2

Chapter 6


Chapter 7 -provides Data Binding and object-oriented Windows Forms set Data-Bound Controls ADO.NET a single of classes. Different data providers work with different data Chapter sources, 8 but - Constraints the programming and Datamodel Relations for all these data providers work in the same way. So, if you know

how to 9work with one Exception data provider, you can easily work with others. It's just a matter of changing class Chapter - ADO.NET Handling names10 and- Working connection Chapter withstrings. the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

Note You can use more than one data provider to access a single data source. For example, you can use Odbc or OleDb data providers to access Microsoft Access databases.


Chapter 14 - Developing Applications ASP.NET because of their object-oriented nature. The ADO.NET classesDatabase are easy Web to use and easy using to understand Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Managed Code

Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET They have all the advantages of the .NET CLR, such as The ADO.NET classes are managed classes. Chapter 19 independency - Mapped Objects: Considerations and DataAll Binding language andPerformance automatic resource management. .NET languages access the same API. Chapter So, if you 20 know - COMhow Interoperability to use theseand classes ADO.NET in C#, you will have no problem using them in VB .NET. Another

big advantage is you don't have to worry about memory allocation and freeing it. The CLR takes care of it Chapter 21 - Messaging for you.22 - SQL Server and ADO.NET: Notes on Performance Chapter Appendix A - Relational Databases: Some Basic Concepts

XML Support

Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Today, XML is an industry standard and the most widely used method of sharing data among applications Index over Internet. As mentioned earlier, in ADO.NET data is cached and transferred in XML format. All List of the Figures components List of Tables and applications can share this data, and data can be transferred via different protocols such as of HTTP. We explain this topic in more detail in Chapters 6 and 7. List Listings List of Sidebars

Visual Data Components VS .NET offers ADO.NET components and data-bound controls to work in visual form. That means you can use these components as you use any Windows controls. You drag and drop these components on Windows and Web Forms, set their properties, and write events. This helps programmers to write less code and develop applications in no time. VS .NET also offers the Data Form Wizard, which helps you create full-fledged database applications without writing a single line of code. Using these components, you can directly bind these components with data-bound controls by setting these control's properties at design-time.Chapter 4 explains this in detail.

Performance and Scalability

Performance andApplied scalability are two major factors when developing Web-based applications and services. ADO.NET: Building Data-Driven Solutions Transferring data from one source to another is a costly affair over the Internet because of connection ISBN:1590590732 by Mahesh Chand and David Talbot bandwidth limitations and rapidly increasing traffic. Using disconnected cached data in XML takes care of Apress © 2003 (928 pages) both of these problems. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions ComparingApplied ADO.NET and ADO by Mahesh Chand and David Talbot

ISBN:1590590732

Prior to ADO.NET, ADO©was Apress 2003 the (928most pages)popular and powerful Microsoft data access technology. So, how does ADO.NET improve on ADO? To understand the of power of ADO.NET, This text provides extensive coverage ADO.NET technologyit's not a bad idea to compare ADO.NET with ADO. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, how to integrate both withare some key differences between The ADO.NET model is inherited from its and predecessor ADO, but there ADO.NET. ADO and ADO.NET. The following sections describe these differences.

Connections and Disconnected Data

Table of Contents

Applied ADO.NET—Building Data-Driven Solutions

With ADO.NET, you use as few connections as possible and have more disconnected data. In fact, it's Introduction recommended to useBasics disconnected data in ADO.NET. In ADO.NET, disconnected data is stored in the Chapter 1 - ADO.NET

form of in-memory DataTable or XML DataSet objects. Having disconnected data not only reduces the - Data Components in Visual Studio .NET load and resource consumption on the server and network, but it also provides better performance.

Chapter 2 Chapter 3


Chapter 4 - ADO.NET in Connected The ADO.NET DataSet not only Environments supports disconnected data, but it provides rich features in comparison Chapter 5 - recordset. Handling ADO.NET Events to an ADO A DataSet, which is a collection of DataTable objects, can store data, but it can Chapter 6 -database Integrating XML with ADO.NET also store table schemas and the relationship between multiple tables. Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Chapter 8

- Constraints and Data Relations Recordsets vs. DataSets

Chapter 9


Chapter 10the - Working withrepresentation the ODBC .NETofData In ADO, in-memory dataProvider is the recordset. A recordset is a set of records that can be Chapter 11database - Stored Procedures and Views an entire table, a section of a table, or a join of more than one table. You use SQL statements to

return the of data. You use recordset's MoveNext, MovePrevious,MoveFirst, and MoveLast Chapter 12 -set Oracle, SQLXML, anda Other .NET Data Providers methods navigate through the Data data.Provider Chapter 13to - Developing a Custom Chapter 14 - Developing Database Web Applications using ASP.NET

Note Even though there's no support of move methods in a DataSet, you can implement them using data binding. We discuss data binding in more detail in Chapter 7.


Chapter 16 - ASP.NET Server Controls and Data Binding

Chapter 17 - Building Real-World Web Applications In ADO.NET, the recordset is gone. The new objects introduced in ADO.NET that serve the purpose of the Chapter 18 are - Object-Relational Mapping in .NET recordset the DataSet and DataReader. A DataSet object represents a DataSet, and a Chapter DataReader 19 - Mapped objectObjects: represents Performance a DataReader Considerations in ADO.NET. and Data A DataSet Binding is a collection of one or more

than one DataSet can and alsoADO.NET contain metadata of database tables, such as their relationships, Chapter 20 table. - COMAInteroperability constraints, and primary and foreign keys. A DataTable object represents a table of a DataSet. With Chapter 21 - Messaging the help youNotes can have multiple views of the same DataSet. Chapter 22of- the SQLDataView Server and object, ADO.NET: on Performance Appendix A - Relational Databases: Some Basic Concepts

ADataSet doesn't have any move methods to navigate through DataSet records like a recordset does. In ADO.NET, a DataTable is a collection of DataRows. You use a DataRow object to navigate through Appendix C - ADO.NET Frequently Asked Questions the records. ADO.NET also provides DataRelation objects to navigate through master and detail Index records using primary and foreign keys. The DataReader object provides fast-cached, forward-only data List of Figures to read data and navigate through its records. Appendix B - Commonly Used SQL Statements

List of Tables List of Listings

XML Support

List of Sidebars

The ADO.NET model uses XML to store and transfer data among applications, which is not only an industry standard but also provides fast access of data for desktop and distributed applications. ADO uses COM marshaling to transfer data among applications, which is not only hard to program but also not as efficient or reliable as XML because of its limitations, its data types and their conversions, and the nature of COM. Using XML, it's easy to program XML files, and you can also transfer data through firewalls using HTTP, which isn't possible using COM marshaling.

ADO.NET: Building Data-Driven Solutions Overview ofApplied ADO.NET Namespaces and Classes by Mahesh Chand and David Talbot

ISBN:1590590732

TheSystem.Data namespace and its five supporting namespaces define the ADO.NET functionality. In Apress © 2003 (928 pages) this section, we briefly describe these namespaces. chaptertechnology describe these namespaces and This text provides extensive coverageLater of ADO.NET classes in more detail. These namespaces reside in the System.Data.dll assembly. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with A namespace is a logical group of Note In the .NET Framework, each class belongs to a namespace. ADO.NET. related types and their definitions. To access a type defined in a namespace, you must reference the namespace by using the Imports keyword or by referencing it directly. For example, the System namespace defines all the system-related functionality. For example, the Console Table of Contents class of the System namespace represents the system console. If you want to access the Applied ADO.NET—Building Data-Driven Solutions Console class, you need to call System.Console or Imports System in your application. Introduction Chapter 1

- ADO.NET Basics The six general ADO.NET namespaces are System.Data,System.Data.Common, Chapter 2 - Data Components in Visual Studio .NET System.Data.OleDb, System.Data.Odbc, System.Data.SqlClient, and Chapter 3 - ADO.NET in Disconnected System.Data.SqlTypes. BesidesEnvironments these namespaces, each new data provider may have its own Chapter 4 - ADO.NET in Connected Environments namespace. For example, if you install the Oracle .NET data provider, the installation adds a new Chapter 5 - Handling ADO.NET Events namespace, the Microsoft.Data.OracleClient namespace, which also belongs to ADO.NET. Chapter 6

- Integrating XML with ADO.NET TheSystem.Data namespace is the Forms core namespace ADO.NET. It consists of the base classes for Chapter 7 - Data Binding and Windows Data-Bound of Controls

the ADO.NET architecture. All data providers use these classes. It defines classes that represent tables, Chapter 8 - Constraints and Data Relations columns, rows, and DataSets. Some common classes from this namespace are DataView, - ADO.NET Exception Handling DataViewManager,DataSet,DataTable,DataRow,DataColumn, and DataRelation. To use Chapter 10 - Working with the ODBC .NET Data Provider these classes in your applications, you need to add a reference to the System.Data namespace. Chapter 9


Chapter 12 All - Oracle, SQLXML, and Other Data Providers Note classes in the .NET Base .NET Class Library are derived from the Object class and represent a Chapter 13 type. - Developing a Custom Data Provider Some authors and documentation also use the word type for a .NET Framework class. Chapter 14 - Developing Database Web Applications using ASP.NET

TheSystem.Data.Common namespace defines common classes. These classes are base classes for Chapter 15 - Using ADO.NET in Xml Web Services concrete provider classes. All data providers share these classes. DBConnection,DataAdapter, Chapter 16data - ASP.NET Server Controls and Data Binding DbDataAdaper, DataColumnMapping, and DataTableMapping are some of the classes defined in Chapter 17 - Building Real-World Web Applications this namespace. To use these classes your application, you need to add a reference to the Chapter 18 - Object-Relational Mapping in in .NET System.Data.Common namespace in your application. Sql, OleDb, and Odbc.


Chapter 20 - COM Interoperability and ADO.NET TheSystem.Data.OleDb namespace defines classes to work with OLE-DB data sources using .NET Chapter 21 Messaging OleDb data providers. To work with an OLE-DB data source, you must have an OleDb provider for that Chapter 22 - SQL Server ADO.NET: Notes on Performance data source. Each dataand provider component has a class corresponding to it. These classes start with Appendix A Relational Databases: Some Basic Concepts OleDb, followed by the component. For example, the OleDbConnection class represents a Appendix Connection B - Commonly object. Some Used SQL of the Statements common classes of this namespace are OleDbDataAdapter,

OleDbDataReader, OleDbCommand, OleDbCommandBuilder,OleDbError,OleDbParameter, Appendix C - ADO.NET Frequently Asked Questions OleDbPermission, and OleDbTransaction. To use these classes in your application, you need to Index addofaFigures reference to the System.Data.OleDb namespace in your application. List List of Tables

Similar to the System.Data.OleDb namespace, the System.Data.Odbc namespaces define Odbc .NET data provider classes to work with the ODBC data sources. To work with ODBC data sources, you List of Sidebars need to install an ODBC driver for a database. The System.Data.Odbc namespace classes start with Odbc, followed by the component. For example, the OdbcConnection class represents a Connection object. Some of the common classes of this namespace are OdbcDataAdapter,OdbcDataReader, OdbcCommand,OdbcCommandBuilder,OdbcError,OdbcParameter,OdbcPermission, and OdbcTransaction. To use these classes in your application, you need to add a reference to the System.Data.Odbc namespace in your application. List of Listings

TheSystem.Data.SqlClient namespaces define Sql .NET data provider classes to work with SQL Server 7.0 or later databases. Similar to Odbc and OleDb classes, the classes in this namespace start with Sql, followed by the component. For example, common classes are SqlConnection, SqlDataAdapter,SqlCommand,SqlDataReader, and SqlTransaction.

The last namespace, System.Data.SqlTypes, provides a group of classes representing the specific Applied ADO.NET: Data-Driven Solutions types found in SQL Server. Some of Building these classes are SqlBinary, SqlMoney,SqlString,SqlInt32, ISBN:1590590732 by Mahesh Chand and David Talbot SqlDouble,SqlDateTime, and SqlNumeric. Apress © 2003 (928 pages)

We discuss theseThis namespaces, classes, andcoverage their members in more detail in Chapters 3 and 4. text provides extensive of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



AppliedADO.NET ADO.NET: Building Data-Driven Solutions Understanding Components by Mahesh Chand and David Talbot

ISBN:1590590732

You can categorize ADO.NET components into three categories: disconnected, common or shared, and Apress © 2003 (928 pages) the .NET data providers. The disconnected components build thetechnology basic ADO.NET architecture. You can This text provides extensive coverage of ADO.NET use these components (or classes) with or without data providers. For example, you can use a including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look or at common XML DataTable object with or without data providers. Shared components are the base classes and classes, and providers. how to integrate bothprovider with for data providersnamespaces and are shared by all data The data components are specifically ADO.NET. designed to work with different kinds of data sources. For example, Odbc data providers work with ODBC data sources, and OleDb data providers work with OLE-DB data sources. Table of Contents

Figure 1-4 represents the ADO.NET components model and shows how the components work together.

Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8 - 1-4: Constraints and Data components Relations Figure The ADO.NET model Chapter 9 - ADO.NET Exception Handling

Adata provider is a set ofthe components, Connection,Command,DataAdapter, and Chapter 10 - Working with ODBC .NET such Data as Provider DataReader. TheProcedures Connection is the first component that talks to a data source. The Connection Chapter 11 - Stored and Views

object establishes a connection to a data source and is used in Command and DataAdapter objects as a connection reference. A Command object executes a SQL query and stored procedures to read, add, Chapter 13 - Developing a Custom Data Provider update, and delete data in a data source via a DataAdapter. The DataAdapter is a bridge between a Chapter 14 - Developing Database Web Applications using ASP.NET DataSet and the connection. It uses Command objects to execute SQL queries and stored procedures. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


Chapter - ASP.NET Server andcommon Data Binding All data16providers share theControls ADO.NET components. These components represent the data. Chapter 17 Building Real-World Web Applications Some of the common components are DataSet,DataView, and DataViewManager. The DataSet Chapter uses XML 18 -toObject-Relational store and transfer Mapping data between in .NET the applications and the data provider. A DataSet is a set of

DataTable objects. A DataTable represents a database table.Binding The DataView and Chapter 19 - Mapped Objects: Performance Considerations and Data DataViewManager objects provide single or multiple views of a DataSet. You can attach a DataView Chapter 20 - COM Interoperability and ADO.NET or a DataViewManager directly to data-bound controls such as a DataGrid or a DataList. Other Chapter 21 - Messaging common DataRow, DataColumn, and so on. Now let's break down the Chapter 22 components - SQL Server are andDataTable, ADO.NET: Notes on Performance ADO.NET to see how it works. Appendix A -model Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

The Connection Object

Appendix C - ADO.NET Frequently Asked Questions Index

The object is the first component of ADO.NET that we should talk about. A connection sets List ofConnection Figures

a link between a data source and ADO.NET. A Connection object sits between a data source and a DataAdapter (via Command). You need to define a data provider and a data source when you create a List of Listings connection. With these two, you can also specify the user ID and password depending on the type of data List of Sidebars source.Figure 1-5 shows the relationship between a connection, a data source, and a DataAdapter. List of Tables


ISBN:1590590732


Table of Contents Applied Figure ADO.NET—Building 1-5: The relationship Data-Driven between Solutions Connection,DataAdpater, and a data source Introduction

You can connectBasics a Connection object to a Command object to execute SQL queries, which you can Chapter 1 also - ADO.NET use to retrieve, update, and delete data .NET in a data source. Figure 1-6 shows the relationship between Chapter 2 - Dataadd, Components in Visual Studio theCommand and Connection objects.

Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Figure 1-6: The relationship between the Command object and the Connection object

Chapter 9

- ADO.NET Exception Handling TheConnection object alsoODBC plays.NET a useful in creating a transaction. Transactions are stored in Chapter 10 - Working with the Data role Provider

Transaction objects, and Transaction classes have all those nice features for dealing with Chapter 11 - Stored Procedures and Views transactions such as commitand andOther rollback. 1-7 shows the relationship between the Connection Chapter 12 - Oracle, SQLXML, .NETFigure Data Providers object and transaction. Chapter 13 - aDeveloping a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

Figure 1-7: Creating a transaction from a Connection object

Chapter 18 - Object-Relational Mapping in .NET


Each data provider has a Connection class. The OleDbConnection,SqlConnection, and

Chapter 20 - COM Interoperability and ADO.NET OdbcConnection classes represent the Connection object of the OleDb, Sql, and Odbc data Chapter 21 Messaging providers, respectively. Chapter 22 - SQL Server and ADO.NET: Notes on Performance

NoteA ADO.NET are discussed in more detail in "The Connection: Connecting to a Data Appendix - Relationalconnections Databases: Some Basic Concepts section ofSQL Chapter 4. Appendix B Source" - Commonly Used Statements Appendix C - ADO.NET Frequently Asked Questions

The Command Object

Index

List of Figures

You usually use the Command object to execute SQL queries and stored procedures. You can execute List of will Tables SQL List of queries Listings to return data in a DataSet or a DataReader object. To retrieve, add, update, and delete data, you use SELECT,INSERT,UPDATE, and DELETE SQL queries. A DataAdapter generated using List of Sidebars the VS .NET Integrated Development Environment (IDE) has these queries. Figure 1-8 shows the relationship between a DataAdaper and a Command object.


ISBN:1590590732


1-8: The relationship between DataAdapter and Command Table Figure of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Similar to the Connection class, each data provider has its own Command class. Each data provider has Chapter 1 - ADO.NET aConnection class.Basics The OleDbCommand,SqlCommand, and OdbcCommand classes represent the Chapter 2 -object Data Components inSql, Visual Studio Command of the OleDb, and Odbc.NET data providers, respectively. Chapter 3 - ADO.NET in Disconnected Environments

You call ExecuteReader method of a Command object, which executes the query and returns data in Chapter 4 the - ADO.NET in Connected Environments aDataReader object (see Figure 1-9). Chapter 5 - Handling ADO.NET Events Chapter 6


Chapter 7


Chapter 8


Chapter 9

- ADO.NET Exception Handling Figure Creating a DataReader from a Command object Chapter 10 - 1-9: Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

Note ADO.NET commands are discussed in more detail in "The Command: Executing SQL Statements" section of Chapter 4.



The Command Builder

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

The SQL SELECT command is fairly easy to construct. Even if you don't know how to construct a SQL

Chapter 17command, - Building Real-World Web Applications SELECT the Query Builder in VS helps you. But notice there are three other commands in Chapter Mapping in .NET Figure 18 1-8-toObject-Relational construct: InsertCommand, UpdateCommand, and DeleteCommand. These commands Chapter - Mapped Objects: Considerations Data Binding can get19 quite complicated in Performance .NET because they requireand complex parameter objects and often involve Chapter 20 of - COM Interoperability ADO.NET large lists columns. ADO.NETand provides a nice utility known as the CommandBuilder that automatically Chapter 21 - Messaging builds these commands for you. Figure 1-10 describes the relationship between CommandBuilder and Chapter DataAdapter. 22 - SQL CommandBuilder Server and ADO.NET:isNotes constructed on Performance with DataAdapter and immediately generates the

remaining Appendix A Command - Relationalobjects. Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List ofFigure Tables 1-10: The relationship between DataAdapter and CommandBuilder List of Listings

Note TheCommandBuilder is discussed in more detail in "Command-Builder: Easing the Work of Programmers" section of Chapter 4.

List of Sidebars

The DataAdapter Object TheDataAdapter object serves as a conduit between the data source and the DataSet. The DataAdapter knows about the DataSet, and the DataAdapter knows how to populate the DataSet. TheDataAdapter also knows about the connection to the data source. Figure 1-11 is a model that shows the simple relationship between the DataAdapter, a DataSet, and a data source.

Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

Figure 1-11:Apress The relationship between DataAdapter and DataSet © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and As you can see from Figureand 1-11, the aFill method oflook a DataAdapter fills data from a DataAdapter to interfaces, takes comprehensive at XML theDataSet, andnamespaces the UPDATE method makes DataSet changes the final data source. and classes, and how to integrate both to with ADO.NET.

There's a DataAdapter available for each data provider. OleDbDataAdapter,SqlDataAdapter, OdbcDataAdapter represent the DataAdapter classes for OleDb, Sql, and Odbc data providers, Table of Contents respectively. Applied ADO.NET—Building Data-Driven Solutions

Note ADO.NET DataAdapters are discussed in more detail in "The DataAdapter: Adapting to Your Introduction section of Chapter 4. Chapter 1 Environment" - ADO.NET Basics Chapter 2


- ADO.NET in Disconnected Environments DataSet Structure

Chapter 3 Chapter 4

- ADO.NET in Connected Environments ADataSet object falls into theEvents disconnected components category. You can use it with or without data Chapter 5 - Handling ADO.NET

providers. DataSet consists of a collection of tables, rows, columns, and relationships. Figure 1-12 Chapter 6 -The Integrating XML with ADO.NET illustrates relationship between a DataSet and its contents. Chapter 7 the - Data Binding and Windows Forms Data-Bound Controls Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - 1-12: Relational Basicclasses Concepts Figure TheDatabases: relationshipSome between in a DataSet Appendix B - Commonly Used SQL Statements

As you can see from Frequently Figure 1-12, a DataSet is a collection of DataTables and DataRelations. All Appendix C - ADO.NET Asked Questions DataTable objects of a DataSet are accessed through the Tables property, which represents a Index collection of DataTable objects. The Relations property of a DataSet represents the collection of List of Figures DataRelation objects associated with a DataSet. List of Tables List of Listings

ADataTable is a collection of DataRow,DataColumn, and Constraint objects. The Rows,

List of Sidebars Columns, and Constraints properties of a DataTable represent a collection of DataRow,

DataColumn, and Constraint objects. DataRow,DataColumn, and Constraint are the smallest units of a DataSet, and they represent a table row, column, and constraint, respectively. Note The DataSet object is discussed in more detail in the "The DataSet: The Heart of ADO.NET" section of Chapter 3 and the "The DataSet in Connected Environments" section of Chapter 4.

DataSets in DataViews Another thing you can do with the contents of DataSets is sort and filter them using DataViews. You can have multiple views of a single DataSet. A DataView is a view of your data created according to certain criteria. Each DataView has a one-to-one mapping to a DataTable in a DataSet. For example, say

you have three tables in a DataSet: table1, table2, and table3. Using three different data tables and data Applied this ADO.NET: Building Data-Driven Solutions views, you can represent DataSet in three different views. Using sort and filters, you can even sort ISBN:1590590732 by Mahesh Chand and David Talbot and filter the data based on some criteria. Figure 1-13 shows three different views of a DataSet in the Apressdata © 2003 (928 pages) form of three different views. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Figure 1-13: The relationship between DataSet and DataView objects

Chapter 5

- Handling ADO.NET Events ADataView can directly attach data-bound controls such as a DataGrid,DataList, or a combo Chapter 6 - Integrating XML with to ADO.NET

box. We this data binding in Chapter and Chapter 7 in more detail. Chapter 7 cover - Data Binding and Windows Forms2Data-Bound Controls Chapter 8


OK, enough theory. Let's see how to write your first database application and get some hands-on - ADO.NET Exception Handling experience with ADO.NET.

Chapter 9


Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions Writing ADO.NET Applications by Mahesh Chand and David Talbot

ISBN:1590590732

It's now time to write your first (928 ADO.NET Apress © 2003 pages) application. In the following sections, we discuss the necessary steps required to This writetext a database application using ADO.NET. provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Choosing a .NET Data Provider

The first step of writing your first ADO.NET application is to decide what .NET data provider you'll use in your application. As discussed previously, there are many data providers that work with multiple data Table of Contents sources. Some of the available data providers are OleDb, Sql, Odbc, and Oracle. You use the OleDb data Applied ADO.NET—Building Data-Driven Solutions provider to access OLE-DB data sources. The Sql data provider works with SQL Server 7.0 or later Introduction databases. The Odbc data provider works with ODBC data sources, and the Oracle data provider works with Oracle databases. You can also use more than one data provider to access the same database. For Chapter 1 - ADO.NET Basics example, you can use the OleDb and Odbc Chapter 2 - Data Components in Visual Studiodata .NETproviders to work with Microsoft Access databases. Chapter 3


Note Some documentation and authors represent the Sql data provider as the SqlClient data provider. - ADO.NET in Connected Environments This may be because the Sql data provider is defined in the SqlClient namespace.

Chapter 4 Chapter 5


Chapter - Integrating ADO.NET For this6example, you'llXML learnwith how to build an application that uses OleDb data providers to access an Chapter 7 Data Binding and Windows Data-Bound Access 2000 database. In the "Using aForms DataSet to Read Controls Data" section, you'll learn how to create an Chapter 8 - that Constraints and Data Relations application uses Sql data providers to access a SQL Server 2000 database. Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

Adding Namespace References


Chapter 12 - Oracle, and Other .NET After you've chosenSQLXML, your data provider, you Data needProviders to add references to the assembly and include the namespaces in your project. The System.Data.dll assembly defines ADO.NET namespaces. You can Chapter 13 - Developing a Custom Data Provider

add references to the project using Project Ø using Add Reference Chapter 14 - Developing Database Webthe Applications ASP.NET option. The .NET tab of the Add Reference box lists all the available .NET assemblies (see Figure 1-14). Select the Chapter 15 - dialog Using ADO.NET in Xml Web Services System.Data.dll assembly. Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 1-14: Adding a reference to the System.Data.dll assembly After selecting the System.Data.dll assembly, click the Select button and then the OK button. This action adds the System.Data assembly and related namespace references to your project. After adding a reference to the assembly, you need to include namespaces in your project by using the Imports directive. The Imports directive imports a namespace definition in a project. The following code shows how to import the System,System.Data,System.Data.Common, and

System.Data.OleDb namespaces:


Imports Imports Imports Imports

ISBN:1590590732

System Apress © 2003 (928 pages) System.Data This text provides extensive coverage of ADO.NET technology System.Data.OleDb including ADO.NET internals, namespaces, classes, and System.Data.Common interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Note If you are using the Sql data provider, you need to include the System.Data.Sql namespace. If you are using the Odbc data provider, you need to include the System.Data.Odbc Applied ADO.NET—Building Data-Driven Solutions namespace.

Table of Contents Introduction Chapter 1

- ADO.NET Basics

Establishing a Connection Chapter 2 - Data Components in Visual Studio .NET Chapter 3

- ADO.NET in Disconnected Environments Now, the next step is to create a Connection object. You create a Connection object using the data

Chapter 4 Connection - ADO.NET in Connected Environments provider's class. In the following code, the OleDbConnection class creates a connection Chapter 5 Handling ADO.NET Events with an Access 2000 database. The OleDbConnection constructor takes one parameter of a string type. Chapter 6 -isIntegrating XML with ADO.NET and it has two parts. First, it has a provider, and second, it has This string called connectionString, Chapter 7 Data Binding and As Windows Forms Controls the path of the data source. you can see, Data-Bound the following code uses the Microsoft.Jet.OLEDB.4.0 Chapter 8 and - Constraints and Data Relations provider the northwind.mdb data source: Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider Dim connectionString As String Chapter 11 -connection Stored Procedures Views 'Create andand command objects Chapter 12 Oracle, SQLXML, and Other .NET Data Providers connectionString = "Provider=Microsoft.JET.OLEDB.4.0;" & _ Chapter - Developing a Custom Data Provider "data13source=C:\\Northwind.mdb" Chapter Dim conn 14 - Developing As OleDbConnection Database Web Applications = New OleDbConnection(connectionString) using ASP.NET

'Open15connection Chapter - Using ADO.NET in Xml Web Services conn.Open() Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Note In this sample, the northwind.mdb database path is "C:\\northwind.mdb". You can use any database you want. You just need to change the path and name of the database and Chapter 22 - SQL Server and ADO.NET: Notes on Performance change the table names you are using in the SQL statements to access the data. Chapter 21 - Messaging

Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Creating a Command or DataAdapter Object

Appendix C - ADO.NET Frequently Asked Questions

Index Next, you need to create a DataAdapter or Command object. You create a Command object by using the List of Figures OleDbCommand class. (You'll see a DataAdapter object in the SQL Server example at the end of this List of Tables chapter; see the "Using a DataSet to Read Data" section.) List of Listings

The constructor takes two parameters. The first is a SQL query, and the second is the List ofOleDbCommand Sidebars Connection object. You can create a SELECT SQL query from the Customers table in the Northwind database. The following code shows how to create a Command object: Dim sql As String sql = "SELECT CustomerID, ContactName, ContactTitle FROM Customers" Dim cmd As OleDbCommand = New OleDbCommand(sql, conn)

Filling Data to a DataSet or DataReader Object The next step is to open the connection by calling the Open method of the Connection object and

reading data from the Command object. The ExecuteReader method, OleDbCommand, returns data in Applied ADO.NET: Building Data-Driven Solutions an OleDbDataReader object. A DataReader object is used to read fast and forward only cached data. ISBN:1590590732 by Mahesh Chand and David Talbot The following code shows this: Apress © 2003 (928 pages)

This text provides extensive coverage of ADO.NET technology

Dim reader Asincluding OleDbDataReader = cmd.ExecuteReader() ADO.NET internals, namespaces, classes, and

interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Displaying Data

The of next step is to perform some operation on the data. In this example, you'll write data out to the Table Contents console. The Read method of OleDbDataReader reads data. The DataReader class has a number of Applied ADO.NET—Building Data-Driven Solutions methods that return different types of data (for example, GetString and GetInteger). These methods Introduction take the1 index of the field from which you want to read data. The following code reads data from two fields Chapter - ADO.NET Basics of the Customers table, whose indexes are 0 and 1: - Data Components in Visual Studio .NET

Chapter 2 Chapter 3


While4 reader.Read() Chapter - ADO.NET in Connected Environments Console.Write(reader.GetString(0).ToString() + " ,") Chapter 5 - Handling ADO.NET Events Console.Write(reader.GetString(1).ToString() + " ,") - Integrating XML with ADO.NET Console.WriteLine("") Chapter 7 - Data Binding and Windows Forms Data-Bound Controls End While Chapter 6 Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider

Closing the Connection

Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Finally, the last step is to close the reader and connection objects by calling their Close methods:



reader.Close() conn.Close()

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 You - Mapped Performance and Binding Note must Objects: always close an openConsiderations DataReader. WeData discuss DataReaders in more detail in the Chapter 20 "The - COMDataReader: Interoperability An and EasyADO.NET Walk Through the Data" section of Chapter 4. Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

ADO.NET: Building Data-Driven Solutions Creating a Applied Simple ADO.NET Application by Mahesh Chand and David Talbot

ISBN:1590590732

Now, let's use allApress of the © previous 2003 (928steps pages) and write a console-based application to read data and display it on the console. In this application, you'll read data from the Northwind database's Customers table and display This text provides extensive coverage of ADO.NET technology it on the console.including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces classes, and ahow to integrate both with In this example, you'll use VSand .NET to create console application by selecting Visual Basic Projects and ADO.NET. then choosing the Console Application template from the Templates listing. Name your project FirstAdoNetApp1. Table of Contents

After creating the project, add the Listing 1-1 source code to the project. As you can see from this listing,

Applied ADO.NET—Building Data-Driven Solutions first you import the required namespace. Second, you create a connection and create an Introduction OleDbConnection object by passing the connection string as only one argument. Next, you construct a Chapter 1 statement - ADO.NETand Basics SELECT create an OleDbCommand object by passing the SQL statement and connection Chapter - Data in Visual Studio .NETthe OleDbConnection.Open method. Once a object. 2Then youComponents open the connection by calling Chapter connection 3 - is ADO.NET opened,inyou Disconnected can execute Environments SQL statement by simply calling the ExecuteXXX methods of the

DataReader. As youincan see, theEnvironments code calls the ExecuteReader method, which returns data in an Chapter 4 - ADO.NET Connected OleDataReader object. ThenEvents you read data from the DataReader and display it on the console. The last Chapter 5 - Handling ADO.NET step is 6to close the DataReader and the connection. You do this by calling the Close methods of Chapter - Integrating XML with ADO.NET OleDbDataReader andand OleDbConnection objects. Controls Chapter 7 - Data Binding Windows Forms Data-Bound Chapter 8


Chapter 9


Listing 1-1: Your ADO.NET Application


Imports Chapter 11 -System Stored Procedures and Views Imports Chapter 12 -System.Data Oracle, SQLXML, and Other .NET Data Providers Imports System.Data.OleDb Imports System.Data.Common

Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Module Module1 Sub Main() Chapter 17 - Building Real-World Web Applications Dim connectionString As String ChapterDim 18 -sql Object-Relational As StringMapping in .NET Chapter'Create 19 - Mapped Objects: Performance Considerations and Data Binding connection and command objects Chapter 20 - COM Interoperability and ADO.NET ConnectionString = "Integrated Security=SSPI; Initial Catalog=Northwind; " & _ Chapter - Messaging "Data21Source=localhost;" ChapterDim 22 -conn SQL Server and ADO.NET: Notes on As OleDbConnection = Performance New OleDbConnection(connectionString) Appendix sql A -=Relational "SELECT Databases: CustomerID, Some Basic ContactName, Concepts ContactTitle FROM Customers" Dim cmd As OleDbCommand = New OleDbCommand(sql, conn) Appendix B - Commonly Used SQL Statements 'Open connection Appendix C - ADO.NET Frequently Asked Questions Index conn.Open() 'Call ExecuteReader List of Figures Dim reader As OleDbDataReader = cmd.ExecuteReader() List of Tables Console.WriteLine("Contact Name, Contact Title") List of Listings Console.WriteLine("=======================") List of Sidebars 'Read data until reader has data While reader.Read() Console.Write(reader.GetString(0).ToString() + " ,") Console.Write(reader.GetString(1).ToString() + " ,") Console.WriteLine("") End While ' Close reader and connection reader.Close() conn.Close() End Sub End Module Chapter 16 - ASP.NET Server Controls and Data Binding

Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh ChandYou and should David Talbot Now compile andbyrun the project. see data on the console (see Figure 1-15).

Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Figure 1-15: Displaying data on the console using DataReader


Applied ADO.NET: Using a DataSet to ReadBuilding Data Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

You just saw an example of working with an Access 2000 database. For variety, you'll now see an example Apress © 2003 (928 pages) of using a SQL Server database. Instead of writing a console-based application, this time you'll create a This text provides extensive coverage of ADO.NET technology Windows Forms application and use the VS .NET IDE. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML andSQL classes, andNorthwind how to integrate bothYou'll with read data from the Customers In this application,namespaces you'll use the Server database. ADO.NET. table using the same CustomerId,ContactName, and ContactTitle columns you selected in Listing 1-1 and display data in a DataGrid control. Table of Contents

Begin your first ADO.NET application by launching VS .NET and by creating a new project using File Ø

Applied Data-Driven Solutionsand select the Windows Application template from the NewØ ADO.NET—Building Project. Choose Visual Basic Projects Introduction available templates, name your project DataGridSamp, and click OK. Chapter 1

- ADO.NET Basics

Clicking2 the OK button creates Windows application project. Now you read data from the SQL Server Chapter - Data Components inaVisual Studio .NET Northwind database and display data in a DataGrid control. This example shows the Customers table Chapter 3 - ADO.NET in Disconnected Environments data in a DataGrid control. Chapter 4 - ADO.NET in Connected Environments Chapter 5

- Handling ADO.NET Events Drag a DataGrid control from the Toolbox onto the form using Toolbox Ø Window Forms and then resize

Chapter - Integrating withonto ADO.NET it. Also 6drag a Button XML control the form and assign it a Text property of Fill. Now double-click the Chapter 7 Data Binding and Windows Data-Bound Controls button to write a click event handler forForms the button. Fill data from a database to the DataGrid on the Fill Chapter 8 - Constraints and Data Relations button click event handler. Chapter 9 - ADO.NET Exception Handling

To access Server, the.NET Sql Data .NETProvider data provider, which is defined in the Chapter 10 -SQL Working withyou the use ODBC System.Data.SqlClient Before adding this namespace class, you need to import the Chapter 11 - Stored Procedures namespace. and Views namespace using the Imports statement. Add the following two lines in the beginning of your application: Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

Imports Chapter 14 -System.Data Developing Database Web Applications using ASP.NET Imports Chapter 15 -System.Data.SqlClient Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

You implement your ADO.NET routine inside this method. To retrieve data from the database, you first need to connect to the database using a Connection object. The DataAdapter is the bridge between Chapter 19source - Mapped Considerations and Data Bindingis constructed with two elements in the data (sql)Objects: and thePerformance DataSet (memory). The DataAdapter Chapter 20 COM Interoperability and ADO.NET this example: a SQL SELECT command to tell the DataAdapter which data to extract into the DataSet Chapter - Messaging object to tell the DataAdapter how to connect to the data source. In this example, and the21 Connection Chapter 22 SQL Server and ADO.NET: Notes onContactTitle Performance select the -CustomerId, ContactName, and column data from the Customers table. Appendix A Relational Databases: Some Basic Concepts After creating a DataAdapter, the next step is to create and fill data from a DataAdapter to a DataSet, Appendix which you B -do Commonly by making Used a call SQLtoStatements the Fill method of DataAdapter. The Fill method takes two parameters: a DataSet and a database table name. Appendix C - ADO.NET Frequently Asked Questions Chapter 18 - Object-Relational Mapping in .NET

Index

Finally, you'll want to display the data from the Customers table in the DataGrid control. You do this by simply binding the DataSet to the DataGrid through its DefaultViewManager (Chapters 2 and 4 List of Tables discussDataViewManager in more detail) by using the DataGrid'sDataSource property. You just set List of Listings theDataSource property of the DataSet'sDefaultViewManager. List of Figures

List of Sidebars

Listing 1-2 shows the button click event handler. As you can see, this code creates a connection using the localhost server and the Northwind database, and you create a DataAdapter using the Customers table. After that, create a DataSet object and call the DataAdapter'sFill method. After that, bind DataSet.DefaultViewManager to the DataGrid using the DataSource property of the DataGrid. Listing 1-2: Viewing Data from a SQL Server Database to a DataGrid Control Private Sub Button1_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button1.Click ' Create a Connection Object Dim ConnectionString As String

Dim sql As String Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot ConnectionString = "Integrated Security=SSPI; Initial Catalog=Northwind; " & _ Apress © 2003 (928 pages) "Data Source=localhost;" This text provides extensive coverage=of New ADO.NET technology Dim myConnection As SqlConnection SqlConnection() including ADO.NET internals, namespaces, classes, and myConnection.ConnectionString = ConnectionString interfaces, and takes a comprehensive look at XML sql = "SELECT CustomerID, ContactName, ContactTitle FROM Customers" namespaces and classes, and how to integrate both with Dim adapter As SqlDataAdapter = New SqlDataAdapter(sql, myConnection) ADO.NET. ' Construct the DataSet and fill it Dim dtSet As DataSet = New DataSet("Customers") Table ofadapter.Fill(dtSet, Contents "Customers") Applied'ADO.NET—Building Data-Driven Solutions Bind the Listbox to the DataSet Introduction DataGrid1.DataSource = dtSet.DefaultViewManager

Chapter 1

- ADO.NET Basics

Chapter End Sub 2 - Data Components in Visual Studio .NET Chapter 3


Chapter 4


Chapter 5

- Handling ADO.NET Events Now compile and run the project. Press the Fill button. The output of the program should look like Figure 1Chapter 6 - Integrating XML with ADO.NET

16.

Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

Figure Output of ADO.NET: the ADO.NET in a DataGrid control Chapter 22 - 1-16: SQL Server and Notesapplication on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Caution Make sure your SQL Server is running and the name of the SQL Server is correct. If you're not using a local server, you need to pass the correct server name, with valid a user ID and Index password. We discuss using user IDs and passwords in a connection in Chapter 4. If SQL List of Figures Server isn't running, you will get an exception. Appendix C - ADO.NET Frequently Asked Questions

List of Tables List of Listings List of Sidebars

Summary


ISBN:1590590732

This chapter introduced basics of ADO.NET and its components. You learned why ADO.NET is a Apress ©the 2003 (928 pages) much better dataThis access technology than previous technologies. text provides extensive coverage of ADO.NET ADO.NET technology provides data providers such as OleDb, Sql, and Odbc to work with OLE-DB, SQL Server, and data sources, respectively. After including ADO.NET internals, namespaces, classes, ODBC and and ADO.NET takes a comprehensive at XML that, you learned interfaces, about various objects suchlook as Connection, Command,DataAdapter, namespaces classes, and howas to the integrate both with DataReader,DataSet, andand DataView as well relationships between them. For example, ADO.NET. DataSet is a collection of DataTable objects. A DataTable can attach to a DataView, which can later be bound with data-bound controls. Further, using a DataView's filter and sort properties, you can provide different views of a DataSet and a DataView. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

At the end of this chapter, you learned how to write a simple application to read data from Microsoft Access and SQL Server databases using ADO.NET.

Introduction Chapter 1

- ADO.NET Basics

Chapter 2 2 -isData Components Visual StudioIDE. .NETIt covers how to take advantage of VS .NET IDE wizards Chapter heavily based oninthe VS .NET Chapter 3 - ADO.NET Disconnected Environments and utilities to developindatabase applications without writing much code. You'll probably find this chapter Chapter exciting4because - ADO.NET you'll in learn Connected to build Environments fully functioning database applications by simply writing a couple of

lines of5code. Chapter - Handling ADO.NET Events Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 2: Data Components inISBN:1590590732 Visual Studio .NET by Mahesh Chand and David Talbot Apress ©you 2003 (928the pages) In the previous chapter, saw basics of the ADO.NET model and its components and how they are This text provides extensive coverage ofThe ADO.NET connected to each other in the ADO.NET architecture. Visualtechnology Studio .NET (VS .NET) Integrated including ADO.NET internals, namespaces, classes, and Development Environment (IDE) provides design-time support to work with data components. In this interfaces, and takes a comprehensive look at XML chapter, you'll learn how to use dataand components in the both VS .NET namespaces andthese classes, how to integrate with IDE at design-time to create database applications. Using ADO.NET components (also referred to as data components) is similar to ADO.NET. using any Windows control. You just drag the component from the Toolbox to a form, set its properties and methods, and you're up and running.

Table of Contents

Applied We start ADO.NET—Building this chapter withData-Driven the Server Explorer, Solutions a useful tool for creating database applications. We focus

on developing database applications quickly using data components in VS .NET without writing a lot of Introduction code. We provide a step-by-step tutorial to help you develop and run a project. After that, we discuss Chapter 1 -also ADO.NET Basics theConnection, DataAdapter, Command, and DataView components in more detail. After Chapter 2 - Data Components in Visual StudioDataSet, .NET finishing chapter,in you'll have a good understanding of data components and how to work with them in Chapter 3 this - ADO.NET Disconnected Environments VS .NET. Chapter 4 - ADO.NET in Connected Environments Chapter 5


Creating an ADO.NET Project - Integrating XML with ADO.NET

Chapter 6 Chapter 7


Begin your project by launching the VS .NET IDE and choosing New Ø Project from the Project menu. Chapter 8 - Constraints and Data Relations Choose Visual Basic Projects from Project Types and then pick the Windows Application template. If you Chapter 9 - ADO.NET Exception Handling like, type an appropriate name into the Name field for your first ADO.NET application and click OK. Our Chapter 10 - Working with the ODBC .NET Data Provider project name is MyFirstADONetApp. Chapter 11 - Stored Procedures and Views


Applied ADO.NET: Building Data-Driven Solutions Using the Server Explorer by Mahesh Chand and David Talbot

ISBN:1590590732

The Server Explorer is new to (928 VS pages) .NET; it enables you to manage your database servers and connections. Apress © 2003 You can use the Server Explorer to add a new server of or ADO.NET a data connection This text provides extensive coverage technologyto your list. The Server Explorer allows you to view, add, edit, and delete data in a tabular grid. The Server Explorer also allows you to including ADO.NET internals, namespaces, classes, and takessuch a comprehensive look procedures, at XML create and deleteinterfaces, databaseand objects as tables, stored views, and triggers. namespaces and classes, and how to integrate both with Note If you'veADO.NET. ever used Open Database Connectivity (ODBC) data source names (DSNs) in your

applications, then you might be familiar with the traditional Windows ODBC Administration. With ODBC Administration, you created DSNs using ODBC drivers for a data source and then Table of Contents connected your application using this DSN. Now, you'll hardly use ODBC Administration at all Applied ADO.NET—Building Data-Driven Solutions because the Server Explorer provides connection management services. Introduction

Chapter 1 see - ADO.NET Basics OK, let's how to use the Server Explorer. You can open the Server Explorer by clicking the View Ø Chapter - Data menu Components Server 2Explorer item. in Visual Studio .NET Chapter 3

- ADO.NET in Disconnected Environments Tip4The use of the Explorer isn't limited to SQL Server databases. You can add any type of Chapter - ADO.NET in Server Connected Environments

including MySQL Chapter 5database, - Handling ADO.NET Eventsand Access. Chapter 6

Integrating XML with ADO.NET When you-open the Server Explorer, you'll see two root nodes: Data Connections and Servers. Initially, the

Chapter 7 - Data Binding and no Windows Data-Bound Controls Data Connections node has items Forms listed under it, but the Servers node displays all the available Chapter 8 By - Constraints andServers Data Relations servers. expanding the node, you can see all the servers and services running on your

Chapter 9 The - ADO.NET Exception Handling machine. SQL Servers node of the Server Explorer lists all the available SQL Servers running on that Chapter 10 - Working with the ODBC .NET Data Provider machine. Chapter 11 - Stored Procedures and Views

If you don't any serversand listed in your list, you can right-click the Servers node and select the Chapter 12 - have Oracle, SQLXML, Other .NETServers Data Providers Add Server menu option. This option you to add new servers to the list. You can also unregister a Chapter 13 - Developing a Custom Data allows Provider server by right-clicking it and selecting the "Unregister Server" menu option.


Chapter 15also - Using ADO.NET in Xml Web Services You can manage services running on your server. If you expand the Services node, you'll see a list of Chapter 16 ASP.NET Server Controls Data Binding services running on your system. Byand right-clicking a service, you can even start and stop a service using Chapter 17 -Explorer. Building Real-World Web Applications the Server Chapter 18 - Object-Relational Mapping in .NET

To view19and managed database objects such as tables,and views, orBinding stored procedures, you can simply Chapter - Mapped Objects: Performance Considerations Data expand20 thedatabase server name under the Data Connections node. After that you can expand Chapter COM Interoperability andlisted ADO.NET Tables,21 Views, and Stored Procedures nodes. To view, delete, and update a database table, you rightChapter - Messaging click the table and use the available options.

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Adding a New Connection

Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Adding a new connection is the next step after adding a server (if you're using a server) to the Server Explorer. You add a new connection to your list by right-clicking the Data Connections node and choosing List of Figures the Add Connection option. This brings up a Data Link Properties Wizard. By default, the Connection tab is List of Tables active, but you may want to click the Provider tab. The first tab of this wizard, Provider, displays all the data List of Listings source providers installed on your machine; this is where you select your database provider. The list could List of Sidebars contain any OLE-DB provider, Jet OLE-DB, or other data driver available on your computer. Index

The second tab of this wizard, Connection, lets you pick your server and corresponding data source. The drop-down list displays all the available servers. Our server is a SQL Server with the default name localhost. After selecting a server, the Database drop-down list displays all the available databases on the server. Select the Northwind database in this example. You can also pick what security mode you want to use for your connection on this tab. You can use the user ID and password of a SQL Server or use the Windows NT Integrated security option. By clicking the Test Connection button, you can make sure your database connection is working. If you've provided an incorrect user ID or password, the test will throw an error. The third tab, Advanced, is for setting connection timeout and access permissions. You can give this connection read, write, or other permissions using the Advanced tab. The last tab, All, shows you all

properties of the connection in a list, such as server name, connection timeout, data source, initial catalog ADO.NET: Building Data-Driven Solutions (database name),Applied security, and other network options. You can also edit this data from this tab by just by Mahesh Chand and David Talbot double-clicking a particular property and editing the value of it.ISBN:1590590732 Apress © 2003 (928 pages)

After adding a data connection, you'll see that the wizard adds a node This text provides extensive coverage of ADO.NET technology including ADO.NET internals, classes,root andnode. If you expand this node, you (Servername.DatabaseName.dbo) to thenamespaces, Data Connections interfaces, and takes comprehensive look at XML can see the database objects such asatables, views, stored procedures, and functions. namespaces and classes, and how to integrate both with ADO.NET.

Managing and Viewing Data Table of Contents As mentioned earlier, the Server Explorer not only lets you add server and database connections, but it Applied ADO.NET—Building also lets you manage andData-Driven view data. Solutions You can add, update, and delete data from a database. Of course, Introduction you must have read and write permissions on the server to read and write data. The Server Explorer also Chapter 1 options - ADO.NET Basics new databases and objects, including tables, views, stored procedures, and provides for creating Chapter 2 - can Datado Components in Visual Studio (Data .NET Connections or Servers). so on. You this from both root nodes Chapter 3 - ADO.NET in Disconnected Environments

The Server Explorer shows database objects in a tree structure. Each database is a tree node of the Chapter 4 - ADO.NET in Connected Environments

server. As -you expand the Northwind database node, for example, you can see its children listed as tables, Handling ADO.NET Events stored procedures, and views.

Chapter 5 Chapter 6


Chapter 7 - Data and Windows Forms Data-Bound If you expand thisBinding connection by double-clicking it, you'll Controls notice it shows tables, views, and stored Chapter 8 - Constraints and Data Relations procedures. You can further expand these items to see them in more detail. Chapter 9

- ADO.NET Exception Handling Note discuss stored procedures and Provider views in more detail in Chapter 11. Chapter 10 We - Working with the ODBC .NET Data Chapter 11 - Stored Procedures and Views

Besides showing a list of database objects such as tables, views, stored procedures, and functions, the Server Explorer also lets you retrieve, add, edit, and delete data from a data source. You can always Chapter 13 - Developing a Custom Data Provider double-click to view the data of a table. Alternatively, right-clicking a database object (such as a table) Chapter 14you - Developing Database Web using provides menu options based on Applications the selection. ForASP.NET example, you can right-click and then select the Chapter 15 Using ADO.NET in Xml Web Services Retrieve Data from Table menu option to retrieve data from that table. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


Now, if 17 you- Building retrieve data from the Employees table by double-clicking or using the Retrieve Data from Chapter Real-World Web Applications Table option, data will be displayed editable grid. You can edit this data at any time-again, assuming Chapter 18 - Object-Relational Mappingininan .NET you have correctObjects: permissions. For example, to delete a row a collection of rows, select the rows and Chapter 19 the - Mapped Performance Considerations and DataorBinding hit Delete right-click the selected and then hit the Delete option. The right-click option of the grid Chapter 20 or - COM Interoperability and rows ADO.NET also provides you options to move to the grid's first, next, previous, and last records.

Chapter 21 - Messaging

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions Using Visual Data Components by Mahesh Chand and David Talbot

ISBN:1590590732

At this time, ADO.NET three Apresshas © 2003 (928base pages)data providers and multiple add-on data providers to work with various kinds of data sources, including SQLcoverage Server, OLEDB datatechnology sources, and ODBC data sources. What This text provides extensive of ADO.NET do we mean by base data providers? Well, initially Microsoft released including ADO.NET internals, namespaces, classes, and only three data providers; now, based interfaces, and takes aand comprehensive at XML new data providers to the library. For on additional requirements, Microsoft third parties look are adding namespaces andCore classes, how to Development integrate both provide with example, Microsoft, Oracle, and Laband Software three different data providers for ADO.NET. the Oracle database. (We discuss these new data providers in later chapters.) The main class hierarchy model of these data providers remains the same, so programmers will have no problem switching between dataof providers. Table ContentsSome of these data providers are OleDb, Sql, Odbc, and Oracle. In this chapter, we concentrate on the OleDbData-Driven and Sql data providers. Later chapters discuss the ODBC, Oracle, and other data Applied ADO.NET—Building Solutions providers. Introduction Chapter 1

- ADO.NET Basics

Tip You can even write your own custom data provider. ADO.NET provides a set of interfaces, which Chapter 2 - Data Components in Visual Studio .NET you must implement to write your own data provider. Chapter 13 of this book covers writing custom Chapter 3data - ADO.NET in Disconnected Environments providers. Chapter 4

- ADO.NET in Connected Environments You can the dataADO.NET providerEvents components at design-time in VS .NET. The data provider components are Chapter 5 use - Handling

available design-timeXML via with the Toolbox. Chapter 6 at - Integrating ADO.NETThe Toolbox's Data tab shows you the available data controls in VS .NET. the components you mayData-Bound see are DataSet, Chapter 7 Some - Data of Binding and Windows Forms ControlsDataView, SqlConnection, SqlCommand, SqlDataAdapter, OleDbConnection,OleDbCommand,OleDbDataAdapter, Chapter 8 - Constraints and Data Relations OdbcCommand, OdbcCommandBuilder,OdbcConnection, and OdbcDataAdapter. These - ADO.NET Exception Handling components are available only when you're in a design view. Chapter 10 - Working with the ODBC .NET Data Provider Chapter 9

Chapter - Stored Procedures Tip11 You can open Toolboxand by Views using the View Ø Toolbox menu item. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

As mentioned briefly inaChapter theProvider .NET Framework Library contains many ADO.NET data providers, Chapter 13 - Developing Custom 1, Data including Sql, and Odbc.Web The Applications OleDb datausing provider wraps up the native OLE-DB COM Application Chapter 14 OleDb, - Developing Database ASP.NET Programming Interface (API) for working with OLE-DB data sources. To access an OLE-DB data source, Chapter 15 - Using ADO.NET in Xml Web Services you need install anServer OLE-DB data and provider that database. Sql data providers work with SQL Server 7 Chapter 16 to - ASP.NET Controls Data for Binding or later17 databases. data providers wrap up the ODBC API to work with ODBC data sources (with the Chapter - BuildingOdbc Real-World Web Applications help of the ODBC Administration and ODBC drivers). Chapter 4 discusses these data providers in more detail. Microsoft and other vendors might introduce more data providers, which you can add to the library Chapter 19 - Mapped Objects: Performance Considerations and Data Binding later. Chapter 18 - Object-Relational Mapping in .NET


Chapter 21 - Messaging In the .NET Framework, each of these data providers has its own namespaces. For instance, the Chapter 22 - SQL Server and ADO.NET:consists Notes onofPerformance System.Data.OleDb namespace classes belonging to the OleDb data providers. All of these Appendix namespace A - Relational classes start Databases: with OleDb. Some The BasicMicrosoft.Data.ODBC Concepts and System.Data.SqlClient Appendix namespaces B - Commonly consist ofUsed classes SQL belonging Statementsto the Odbc and Sql data providers, respectively. Similar to

OleDb, classes in Odbc start with Odbc, and classes in SqlClient start with Sql. Appendix C - ADO.NET Frequently Asked Questions Index

In VS .NET, some of these classes (or objects) are available from the Toolbox; you can drag them onto a form like any other Windows control in the Toolbox. These controls are called data components.


List Listings VSof.NET also provides a set of data-bound controls. The DataGrid,ListBox, and DataList are good List of Sidebars examples of some of these data-bound controls. It's fairly easy to work with these controls. You just set a

few properties, and they're ready to display your data. For example, setting a DataGrid control's DataSource property displays data from a DataSet object. We use these data-bound controls in the examples throughout this book. In the next section, we discuss how you can add these components to your Windows Forms applications and set their properties and methods at design-time with the help of the .NET wizards.

Understanding Data Connections To connect to a data source, the first thing you need to learn about is a data connection. Each data provider has a Connection class, and if you're using the VS .NET IDE, you can see these class

objects as components in the Data tab of the Toolbox. For example, the SqlConnection, Applied ADO.NET: Building Data-Driven OdbcConnection, and OleDbConnection class objectsSolutions represent a connection for the Sql, Odbc, and ISBN:1590590732 by Mahesh Chand and David Talbot OleDb data providers, respectively: Apress © 2003 (928 pages)

SqlConnection creates andextensive managescoverage SQL Server database connections. This text provides of ADO.NET technology including ADO.NET internals, namespaces, classes, and

OdbcConnection interfaces, creates and takes and manages a comprehensive connections look attoXML ODBC data sources. namespaces and classes, and how to integrate both with ADO.NET.creates and manages connections to OLE-DB data sources. OleDbConnection

In the VS .NET IDE, you can create a Connection in many ways. You can use the IDE to add a

Table of Contents Connection object to a project, create it programmatically, or use DataAdapters that automatically Applied Data-Driven create ADO.NET—Building a Connection object for you.Solutions In this chapter, we concentrate on adding a connection through the Introduction VS .NET IDE. Chapter 1

- ADO.NET Basics

Chapter 2

- Data Components in Visual StudioIDE .NETvs. Manual Coding

Chapter 3


In some cases, you may not know if you should use the IDE or write code manually. Actually, creating a - ADO.NET in Connected Environments connection and other objects such as a Command manually is usually much better. Those types of Chapter 5 - Handling ADO.NET Events objects only require a few lines of code, and creating them manually allows you to know where the Chapter 6 - Integrating XML with ADO.NET code is and what it means. If you use the VS .NET IDE, it adds a connection and other data Chapter 7 - Data Binding and Windows Forms Data-Bound Controls components but sometimes also writes lots of code that is difficult to understand. For example, adding Chapter 8 - Constraints and aData Relations aDataAdapter adds great deal of code that you may not need. If you want to modify it, you'll almost Chapter 9 ADO.NET Exception Handling certainly get lost if you don't have a lot of experience. Chapter 4


Now, nextProcedures question probably is, "Why do I need to use the IDE at all?" Well, the IDE may help you Chapter 11 your - Stored and Views if you know how to and create connection and other objects because it writes code for you. Chapter 12 don't - Oracle, SQLXML, Other .NET Datastrings Providers Basically, the IDE isa useful part-time ADO.NET developers-those who write non-database-related Chapter 13 - Developing Customfor Data Provider code occasionally use ADO.NET. It's alsousing useful for beginners, who want to have their application Chapter 14 but - Developing Database Web Applications ASP.NET ready running in nointime. But after completing this book, I bet you'll hate using IDE. Chapter 15 -and Using ADO.NET Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping to in .NET The easiest way to add a connection a project in VS .NET is to drag a connection component Chapter 19 - Mapped OleDbConnection, Objects: Performance Considerations and Data from Binding (SqlConnection, or OdbcConnection) the Toolbox's Data tab to a form. Chapter 20 -you COM Interoperability and ADO.NET After that, can set the connection's properties using the Properties window. For this demonstration, drop

aSqlConnection from the Toolbox onto the form. You can set the SqlConnection properties from the Chapter 21 - Messaging Properties by right-clicking theNotes SqlConnection and selecting the Properties menu item. Chapter 22 -window SQL Server and ADO.NET: on Performance Appendix A - Relational Databases: Some Basic Concepts

Note that the default connection name is the class name with a unique name appended to it. Because this is the first connection, the name is sqlConnection1.



Index As you can see in the Properties window, a connection's properties include Database, List of Figures ConnectionTimeout, DataSource,PacketSize,WorkstationId,Name, and List ConnectionString. of Tables List of Listings

The connection properties depend on the data provider. Some properties may not be available for List ofNote Sidebars some data providers. For example, the WorkstationId property is available in Sql data providers but not in OleDb or ODBC data providers.

Understanding Connection Strings TheConnectionString property is the main property of a connection. By clicking the drop-down list of theConnectionString property, you can see all the available data connections. If you don't have a data connection, you can use its New Connection option, which launches the Data Link Properties Wizard. (Refer to the earlier "Using the Server Explorer" section for more information.) For this example, we use the database server name MCB instead of localhost. The SQLConnection string for server MCB looks like following:

Applied ADO.NET: Building Data-Driven Solutions

data source=MCB;initial catalog=Northwind;integrated security=SSPI;" & _ ISBN:1590590732 by Mahesh Chand and David Talbot "persist security info=False;workstation id=MCB;packet size=4096 Apress © 2003 (928 pages)

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Note In Chapter 4, we discuss a connection and properties more detail and show how to set them namespaces and classes, and how to its integrate bothinwith programmatically. ADO.NET. You can also use a user ID and password in a connection string.

Working with SQL DataAdapters

Table of Contents


ADataAdapter is another important component of a data provider. Similar to a connection, each data

Introduction provider has a corresponding DataAdapter class. All DataAdapters in ADO.NET work in same way, Chapter 1 - ADO.NET Basics which means if you know how to work with Sql DataAdapters, you can use OleDb, ODBC, and other Chapter 2 - Data Components in Visual Studio .NETOleDbDataAdapter, and OdbcDataAdaper classes DataAdapters easily. The SqlDataAdapter, Chapter 3 DataAdapter - ADO.NET in Disconnected Environments represent components in Sql, OleDb, and Odbc data providers, respectively. Chapter 4

- ADO.NET in Connected Environments Besides5 creating a DataAdapter programmatically (see Chapter 4 for more details), VS .NET provides Chapter - Handling ADO.NET Events

various6ways to create DataAdapters. Chapter - Integrating XML with ADO.NETTwo common ways are by using the Server Explorer and by using the Data Configuration Wizard. Chapter 7 Adapter - Data Binding and Windows Forms Data-Bound Controls Chapter 8


Creating- ADO.NET DataAdapters with the Server Explorer Exception Handling

Chapter 9

Chapter Working with the ODBC .NET Data It's easy10to-create a DataAdapter using theProvider Server Explorer. You just drag and drop database objects to a Chapter 11 Stored Procedures and Views form and the IDE takes care of everything for you. The IDE writes code that you can use programmatically Chapter - Oracle, SQLXML, and Other Providers or bind12 data controls at design-time. To.NET addData a new connection to a project, expand your database in the Chapter - Developing a Custom Server 13 Explorer, and drag a tableData fromProvider the Server Explorer to your form. For this example, expand the Chapter Northwind 14 -database Developing in Database the ServerWeb Explorer Applications and drop using theASP.NET Employees table to the form. Chapter 15 - Using ADO.NET in Xml Web Services

This action adds a SqlConnection and SqlDataAdapter object to the project. You can even drag selected columns or stored procedures onto the form. The VS .NET IDE takes care of the rest. Right-click Chapter 17 - Building Real-World Web Applications the form and choose View Code to examine the code generated by the wizard; in this example, you'll see Chapter 18 - Object-Relational Mapping in .NET oneSqlConnection component and one SqlDataAdapter component along with a set of Chapter 19 - Mapped Objects: Performance Considerations and Data Binding SqlCommand components: Chapter 16 - ASP.NET Server Controls and Data Binding

Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

Friend WithEvents SqlSelectCommand1 As System.Data.SqlClient.SqlCommand Friend WithEvents SqlInsertCommand1 As System.Data.SqlClient.SqlCommand Appendix A - Relational Databases: Some Basic Concepts Friend WithEvents SqlUpdateCommand1 As System.Data.SqlClient.SqlCommand Appendix B - Commonly Used SQL Statements Friend WithEvents SqlDeleteCommand1 As System.Data.SqlClient.SqlCommand Appendix C - ADO.NET Frequently Asked Questions As System.Data.SqlClient.SqlConnection Friend WithEvents SqlConnection1 Index Friend WithEvents SqlDataAdapter1 As System.Data.SqlClient.SqlDataAdapter Chapter 22 - SQL Server and ADO.NET: Notes on Performance


You'll also see that the IDE writes SQL statements and sets the CommandText property of SqlCommand List of Listings objects. Once you have a DataAdapter, you can use it to populate DataSets and work with its List of Sidebars properties. (We discuss DataSet basics and how to construct them manually in Chapter 4.) With the VS .NET IDE, you can even generate DataSets using the visual representation of the DataAdapter. (We discuss how to populate a DataSet using VS .NET IDE wizards in the "Generating Typed DataSets Using a DataAdapter" section of this chapter.)

Creating DataAdapters with the Data Adapter Configuration Wizard The Data Adapter Configuration Wizard is a powerful tool to develop database applications. To see how you can create DataAdapters using this wizard, you'll create a new Windows Forms-based project in the following step-by-step sections. In this first project, you'll learn how to create SQL DataAdapters, read data from a SQL Server data

source, and display the data from a DataAdapter to a DataGrid control. After completing these steps, Applied ADO.NET: Building Data-Driven Solutions you'll see how easy it is to develop database applications using the Data Adapter Configuration Wizard. by Mahesh Chand and David Talbot

ISBN:1590590732

Apress © 2003Template (928 pages) Step 1: Selecting a Project This text provides extensive coverage of ADO.NET technology

To create a new Windows application using VS .NET, select File Øand New Ø Project Ø Visual Basic Projects including ADO.NET internals, namespaces, classes, interfaces, andselect takes an a comprehensive look at XML Ø Windows Application. Next, appropriate directory and type your project name. namespaces and classes, and how to integrate both with

Step 2: Adding aADO.NET. DataGrid Control to the Form Now add a DataGrid control to the form. You do this by just dragging a DataGrid control from the Table of Contents Toolbox's Windows Forms category to the form and resizing it. Applied ADO.NET—Building Data-Driven Solutions

Step 3: Adding a DataAdapter Component Introduction Chapter 1

- ADO.NET Basics

Chapter 4


Next, drag a SqlDataAdapter control from the Toolbox's Data category to the form. As you drop the Chapter 2 - Data Components in Visual Studio .NET SqlDataAdapter the Data Adapter Configuration Wizard pops up. The following sections walk you Chapter 3 - ADO.NET in Disconnected Environments through this wizard. Chapter 5 -Page Handling ADO.NET Events Welcome Chapter 6

- Integrating XML with ADO.NET The first of Binding this wizard just a welcome screen. Click the Next button to move to the next screen. Chapter 7 page - Data and is Windows Forms Data-Bound Controls Chapter 8


Chapter 9


Choose Your Data Connection Page

Chapter 10 - Working the ODBC Provider The second page of with the wizard lets.NET you Data create a new connection or pick from a list of available connections Chapter on your11 machine. - StoredAll Procedures availableand connections Views are listed in the drop-down list. If you don't have any

connections listed inSQLXML, the list, and you Other can click New Connection button, which launches the Data Link Chapter 12 - Oracle, .NETthe Data Providers Properties (discussed previously in the "Adding a New Connection" section). Chapter 13 -Wizard Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Choose a Query Type

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16page - ASP.NET and Data The next of theServer wizardControls is for selecting a Binding SQL query type. If you see this page, three options are Chapter 17 Building Real-World Web Applications available for the SQL Server connection: Chapter 18 - Object-Relational Mapping in .NET

The SQL Statement option allows you to createand a new query. Chapter 19Use - Mapped Objects: Performance Considerations DataSQL Binding Chapter 20 - COM Interoperability and ADO.NET

The Create New Stored Procedure option allows you to create a new stored procedure.


Chapter 22Use - SQL ServerStored and ADO.NET: Notes on Performance The Existing Procedure option allows you to select a stored procedure from the existing Appendix stored A - procedures. Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Note The last two options aren't available for databases that don't support stored procedures.

Appendix C - ADO.NET Frequently Asked Questions Index Generate the SQL Statement List of Figures

The page of the Data Adapter Configuration Wizard lets you build a SQL statement or a stored List of next Tables procedure. List of ListingsYou can type a SQL statement directly into the text box, or you can click the Query Builder button to use the Query Builder to build your SQL statement. List of Sidebars Query Builder The Query Builder option lets you pick tables from your data source. First, select the Employees table to read in the Employee data. You actually have the option of selecting as many as tables you want, but for now select only one table and click the Add button. After clicking the Add button, the Query Builder provides you with an option to select columns of the table. You can check *(All Columns) to select all the columns of a table, or you can check only the columns you want to participate in the SQL statement. If you've ever used the New Query Wizard in Microsoft Access, you'll find that the Query Builder is similar to it. In Access, you can create queries by dragging tables and their columns to the grid (or checking the columns), and the Query Builder builds a SQL query for your action.

In this sample, select EmployeeID,FirstName, and LastName from the Employees table to build your Data-Driven Solutions SQL statements. Applied The SQLADO.NET: statementBuilding after selecting these three columns looks like this: by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

SELECT EmployeeID, LastName, FirstName FROM Employees

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML You can even type this SQL statement directly intotothe text box.both with namespaces and classes, and how integrate ADO.NET.

Note You can even write your own SQL statement if you don't want to use the Query Builder. For performance reasons, if you only want few columns, then use column names instead of using Table of Contents SELECT * statements. Applied ADO.NET—Building Data-Driven Solutions

One more button is available on this page: Advanced Options. By clicking the Advanced Options button, you Introduction launch 1the- Advanced SQL Generation Options page. On this page, there are three options: Generate Insert, Chapter ADO.NET Basics Update, Delete Statements; Use Optimistic Concurrency; and Refresh the DataSet. By default all three Chapter 2 and - Data Components in Visual Studio .NET options are checked. If you don't want to generate INSERT,UPDATE, or DELETE SQL statements, you - ADO.NET in Disconnected Environments should uncheck the first check box.

Chapter 3 Chapter 4


Chapter 5 - ADO.NET Handling ADO.NET Events concurrency. If you don't want your program to implement optimistic By default, uses optimistic Chapter 6 Integrating XML with ADO.NET concurrency, you should uncheck the second check box. Chapter 7


View Wizard Results and Data Relations Chapter 8 - Constraints Chapter 9


The View Wizard Results page shows you the action being taken by the wizard. If everything went well, the wizard generates a message saying, "The data adapter… was configured successfully." For this example, Chapter 11 - section Stored Procedures the Details shows thatand the Views wizard has generated SQL SELECT,INSERT,UPDATE, and DELETE Chapter 12 Oracle, SQLXML, and Other .NET Data Providers statements and mappings. Chapter 10 - Working with the ODBC .NET Data Provider


Now you click the Finish button complete the process. Chapter 14can - Developing Database WebtoApplications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Currently, if you examine the design surface at the bottom of the Form window, you'll see two components: sqlConnection1 and sqlDataAdapter1. The wizard sets the properties of these components for you. Chapter 17 - Building Real-World Web Applications Now you can use the DataAdapter to populate your DataSets. Don't forget to resize the DataGrid you Chapter 18 - Object-Relational Mapping in .NET added to the project. Chapter 16 - ASP.NET Server Controls and Data Binding

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter - COM and Interoperability ADO.NET Properties Step 4:20 Setting Reviewingand DataAdapter Chapter 21 - Messaging

Now that you have a DataAdapter on your form, let's look at the SqlDataAdapter component properties. You can see its properties by right-clicking the adapter and selecting the Properties menu item. Appendix A - Relational Databases: Some Basic Concepts The wizard also shows the available command properties, including InsertCommand,DeleteCommand, Appendix B - Commonly Used SQL Statements SelectCommand, and UpdateCommand. Chapter 22 - SQL Server and ADO.NET: Notes on Performance


Index You can set DataAdapter properties by clicking these properties. . A DataAdapter has four List of Figures properties-SelectCommand, DeleteCommand, InsertCommand, and UpdateCommandSqlCommand List thatofall Tables execute SQL commands on the data source. For example, if you look at the SelectCommand

property, you'll see the SQL SELECT statement. List of Listings List of Sidebars

Note Chapter 4 covers SelectCommand,InsertCommand,UpdateCommand, and DeleteCommand in more detail.

From the Properties window, you can also set CommandText,CommandType,Connection, and other properties. If you double-click CommandText, it pops up the Query Builder where you can rebuild your query. TheTableMapping class represents a mapping of DataColumns in the data source to DataColumns in theDataSet. We discuss DataTables and table mappings in more detail in Chapters 3 and 4. If you click theTableMappings property (which is a collection of TableMapping objects), it brings up the Table Mappings dialog box.

Question and Answer


ISBN:1590590732

Apress © 2003table (928 pages) Q: Why do I need mappings? I've also heard of column mapping. What is it? This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Answers

namespaces and classes, and how to integrate both with ADO.NET.

A:

Sometimes, you won't want to display your actual table names and their columns as Table of Contents defined in a database. For instance, say you have a MyTable table with two fields, a0 and a1. The Data-Driven table storesSolutions a customer's information, and the fields a0 and a1 store customer Applied ADO.NET—Building names and addresses. If you display your table in data components such as a DataGrid, Introduction it will display the table name as MyTable and the column names as a0 and a1, which Chapter 1 - ADO.NET Basics makes no sense to user. Chapter 2


Chapter 3

- ADO.NET in Disconnected Environments Using table mappings, you can change the table name to Customers Table. Using - ADO.NET in Connected column mapping,Environments you can change the columns' names to Customer Name and Customer

Chapter 4 Chapter 5 Chapter 6

- Handling ADO.NET Events Address. After this mapping, DataGrid will display the table name as Customers Table - Integrating XML with ADO.NET and the columns as Customer Name and Customer Address, which make more sense to

Chapter 7

- Data Binding a user. and We discuss Windowstable Forms and Data-Bound column mappings Controls in Chapter 3 in more detail.

Chapter 8


Chapter 9



If you click the TableMappings property, it opens the Table Mappings dialog box. The Table Mappings dialog box has two columns: Source Table and Dataset Table (see Figure 2-1). If you have more than one Chapter - Developing a Custom Dataall Provider table in13 a DataAdapter, you'll see the tables listed in the Source Table list box. By default the source Chapter 14 Developing Database Web Applications using ASP.NET table Table is listed in the list box. The Source Table column is a list of actual columns, and the Dataset Chapter 15 - Using Xml Web Services Table column is aADO.NET list of theincolumn names used in the DataSet. By default, DataSet columns names Chapter - ASP.NET andisData Binding are the16 same as the Server sourceControls table. This useful when you want to use different names in a program. You Chapter can change 17 - Building DataSet Real-World columnsWeb by editing Applications the column itself. Of course, you can't change source columns, Chapter but you18 can - Object-Relational reorder them by Mapping using theinColumn .NET Mappings drop-down list. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


Figure 2-1: Table Mappings dialog box By using this dialog box, you can even delete columns from your mapping using the Delete button. Step 5: Reviewing Other Options

If you look closelyApplied at the DataAdapter's Properties window, you'll see three links: Configure Data Adapter, ADO.NET: Building Data-Driven Solutions Generate Dataset, and Preview Data. ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

The Configure Data Adapter option calls the Data Adapter Configuration Wizard, discussed earlier in this This text provides extensive coverage of ADO.NET technology chapter. If you want to reset the wizard to change your options, you can use this link. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

The Generate Dataset option lets you generate a DataSet for this DataAdapter. The Generate DataSet namespaces and classes, and how to integrate both with option provides you with options that allow you to select whether you want to use an existing DataSet or ADO.NET. create a new DataSet. The Existing option is available only when a typed DataSet is available in your project. Table of Contents

CreateADO.NET—Building a new DataSet with the default name DataSet1. (You can change the DataSet name if you want.) Applied Data-Driven Solutions Clicking the OK button adds a typed DataSet (DataSet1.xsd) to the project. Introduction Chapter 1

- ADO.NET Basics

Chapter 2

and Answer - Data Components in Visual Studio Question .NET

Chapter 3


Chapter 4 Chapter 5

-Q: ADO.NET Connected Environments What'sina typed DataSet? Are there other types of - Handling ADO.NET Events DataSets?

Chapter 6


Chapter 7

-Answers Data Binding and Windows Forms Data-Bound Controls

Chapter 8


Chapter 9

- ADO.NET Exception Handling There are two types of DataSets: typed and untyped. A typed DataSet is represented Chapter 10 -A: Working with the ODBC .NET Data Provider

by an Extensible Markup Language (XML) schema. See the "Typed and Untyped DataSets" section of Chapter 3 for more information.



Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Actually, Generate DataSet option adds class DataSet1 to your project, which is inherited from Chapter 16the - ASP.NET Server Controls and DataaBinding DataSet. you go Real-World to the ClassWeb View, you can see the DataSet1 class and its members. Chapter 17 -IfBuilding Applications Chapter 18 - Object-Relational Mapping in .NET

The Preview Data option enables you to view the DataSet schema. You can even preview the data in the DataSet by pressing the Fill button, which opens the Data Adapter Preview dialog box (see Figure 2-2).


Figure 2-2: Previewing data for the DataAdapter

The Fill Dataset button in Figure 2-2 fills data into a grid based upon the current state of the Applied ADO.NET: Building Data-Driven Solutions SelectCommand in the DataAdapter. The Parameters grid displays available parameters if a ISBN:1590590732 by Mahesh Chand and David Talbot DataAdapter has any. The Clear Results button clears the records. Apress © 2003 (928 pages)

Thisthe text provides extensive coverage of ADO.NET technology Step 6: Reviewing Source Code including ADO.NET internals, namespaces, classes, and

interfaces, takes comprehensive look at XML Now it's time to examine theand code anda see what the wizard has done for you automatically. You can see the namespaces and classes, and how to integrate both with source code by right-clicking the form and selecting the View Source option. ADO.NET.

Note You should take the time to look at the code so you know what goes under the hood when you use the IDE to write your code. It'll help you in the long run. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

All source code generated by the Windows form designer is defined in the InitializeComponent method of the file. Right-click your form and choose View Code. Upon examining the source code, you'll Chapter 1 -the ADO.NET see where wizardBasics has added two components, sqlConnection1 and sqlDataAdapter1, to your Chapter Data Components in Visual Studio .NET source 2file-as well as four SqlCommand components. Scroll down to the Windows Designer Generated Chapter 3 - ADO.NET in Disconnected Environments Code option and expand it. This reveals the contents of the InitializeComponent routine (see Listing 2Chapter 4 - ADO.NET in Connected Environments 1). Introduction

Chapter 5


Listing62-1: Added SqlXML Server Provider Components Chapter - Integrating with ADO.NET Chapter 7


Chapter 8 WithEvents - Constraints and Data Relations Friend DataGrid1 As System.Windows.Forms.DataGrid Chapter Friend 9 - ADO.NET WithEvents Exception SqlDataAdapter1 Handling As System.Data.SqlClient.SqlDataAdapter

Friend WithEvents Chapter 10 - Working with theSqlSelectCommand1 ODBC .NET Data ProviderAs System.Data.SqlClient.SqlCommand Friend WithEvents SqlInsertCommand1 As System.Data.SqlClient.SqlCommand Chapter 11 - Stored Procedures and Views Friend WithEvents As System.Data.SqlClient.SqlCommand Chapter 12 - Oracle, SQLXML, SqlUpdateCommand1 and Other .NET Data Providers Friend WithEvents SqlDeleteCommand1 As System.Data.SqlClient.SqlCommand Chapter 13 - Developing a Custom Data Provider Friend WithEvents SqlConnection1 System.Data.SqlClient.SqlConnection Chapter 14 - Developing Database Web ApplicationsAs using ASP.NET Friend WithEvents DataSet11 As MyFirstADONetApp.DataSet1 Private Sub InitializeComponent() Chapter 16 - ASP.NET Server Controls and Data Binding Me.DataGrid1 = New System.Windows.Forms.DataGrid() Chapter 17 - Building Real-World Web Applications Me.SqlDataAdapter1 = New System.Data.SqlClient.SqlDataAdapter() Chapter 18 - Object-Relational Mapping in .NET Me.SqlSelectCommand1 = New System.Data.SqlClient.SqlCommand() Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Me.SqlInsertCommand1 = New System.Data.SqlClient.SqlCommand() ChapterMe.SqlUpdateCommand1 20 - COM Interoperability and = ADO.NET New System.Data.SqlClient.SqlCommand() ChapterMe.SqlDeleteCommand1 21 - Messaging = New System.Data.SqlClient.SqlCommand() Chapter 22 - SQL Server and Notes on Performance Me.SqlConnection1 = ADO.NET: New System.Data.SqlClient.SqlConnection() Chapter 15 - Using ADO.NET in Xml Web Services

Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Search for the ConnectionString by hitting Ctrl+F to bring up VS .NET's Find dialog box. If you examine Index theof InitializeComponent() method, you'll see that the wizard sets SqlConnection's List Figures ConnectionString property to the following: List of Tables List of Listings

Me.SqlConnection1.ConnectionString = _ List of Sidebars "data source=localhost;initial catalog=Northwind;" & _ "integrated security=SSPI;persist " & _ "security info=False;workstation id=MCB;packet size=4096"

It also sets the CommandText property of the SqlCommand with the corresponding SELECT,INSERT, UPDATE, and DELETE SQL statements. The Connection property of SqlCommand is set to SqlConnection: Me.SqlSelectCommand1.CommandText = "SELECT EmployeeID, LastName, " & _ "FirstName FROM Employees"

Me.SqlSelectCommand1.Connection = Me.SqlConnection1 Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

If you examine Listing Apress 2-2, © 2003 you'll (928see pages) that DataAdapter is connected to a Connection through data commands, and the property is responsible for mapping tables and their columns. Note ThisTableMapping text provides extensive coverage of ADO.NET technology including ADO.NET internals,columns namespaces, classes, and columns generated by the wizard that the table mappings between DataSet and DataSource interfaces, andnames. takes a comprehensive look at XML have exactly the same column namespaces and classes, and how to integrate both with ADO.NET.

Listing 2-2: DataAdapter Connection through TableMapping

TableMe.SqlDataAdapter1.DeleteCommand of Contents = Me.SqlDeleteCommand1 AppliedMe.SqlDataAdapter1.InsertCommand ADO.NET—Building Data-Driven Solutions = Me.SqlInsertCommand1 Introduction Me.SqlDataAdapter1.SelectCommand = Me.SqlSelectCommand1 ChapterMe.SqlDataAdapter1.TableMappings.AddRange(_ 1 - ADO.NET Basics ChapterNew 2 -System.Data.Common.DataTableMapping() Data Components in Visual Studio .NET { _

"Employees", _ ChapterNew 3 -System.Data.Common.DataTableMapping("Table", ADO.NET in Disconnected Environments { _ ChapterNew 4 -System.Data.Common.DataColumnMapping() ADO.NET in Connected Environments "EmployeeID"), _ ChapterNew 5 -System.Data.Common.DataColumnMapping("EmployeeID", Handling ADO.NET Events "LastName"), _ ChapterNew 6 -System.Data.Common.DataColumnMapping("LastName", Integrating XML with ADO.NET "FirstName")})}) ChapterNew 7 -System.Data.Common.DataColumnMapping("FirstName", Data Binding and Windows Forms Data-Bound Controls Me.SqlDataAdapter1.UpdateCommand = Me.SqlUpdateCommand1 - Constraints and Data Relations

Chapter 8 Chapter 9



It looks like the wizard did a lot of the work for you!

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter Step 7:13 Filling - Developing the DataGrid a Custom Control Data Provider with Data Chapter 14 - Developing Database Web Applications using ASP.NET

Until now, you haven't had to write a single line of code. Now, though, you'll add few lines of code and then you'll be all set to see the data from your data source. Now you have two options. First, you can use the Chapter 16 - ASP.NET Server Controls and Data Binding typed DataSet to read the data, and second, you can create a DataSet object programmatically and fill it Chapter 17 - Building Real-World Web Applications using the SqlDataAdapter'sFill method. Chapter 15 - Using ADO.NET in Xml Web Services


Chapter 19 - Mapped Objects: Performance Considerations anditData You'll create a DataSet object programmatically and use to fillBinding data in a DataGrid. Add the code in Chapter Listing 20 2-3-toCOM the Interoperability form load eventand handler. ADO.NET As you can see, this code creates a DataSet object and fills it

by calling Fill method. The Fill method of SqlDataAdapter fills data from a Chapter 21 SqlDataAdapter's - Messaging DataAdapter the DataSet. You Notes call the method in the FillDBGrid method. Once you have a Chapter 22 - SQL to Server and ADO.NET: onFill Performance DataSet you can do anything with it, including creating views for that data. In this example, Appendix A -containing Relational data, Databases: Some Basic Concepts you set aB DataGrid DataSource Appendix - Commonlycontrol's Used SQL Statements property to the DataSet.DefaultViewManager, which binds theC DataSet to theAsked DataGrid control. Appendix - ADO.NETobject Frequently Questions Index

Listing 2-3: Form's Load Event Handler


Private Sub Form1_Load(ByVal sender As System.Object, _ List of Listings ByVal e As System.EventArgs) Handles MyBase.Load Dim ds As DataSet = New DataSet() SqlDataAdapter1.Fill(ds) DataGrid1.DataSource = ds.DefaultViewManager End Sub

List of Sidebars

Another option is to use the typed DataSet you generated using the Generate DataSet option. The wizard added an instance of DataSet1 called DataSet11 to the project. Now just call the Fill method of DataAdapter and bind the DataSet's default view to the DataGrid. Just write the following two lines on the form load event handler:

SqlDataAdapter1.Fill(DataSet11) Applied ADO.NET: Building Data-Driven Solutions DataGrid1.DataSource = DataSet11.DefaultViewManager by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

Finally, build andThis run the using eithercoverage of the two The result looks like Figure 2-3. Easy, text project provides extensive of methods. ADO.NET technology including ADO.NET internals, namespaces, classes, and huh? interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Figure 2-3: Output of the Employee data to a DataGrid control


Applied ADO.NET: BuildingComponents Data-Driven Solutions Using DataSet and DataView by Mahesh Chand and David Talbot

ISBN:1590590732

After discussing DataAdapters data connections, you should have a pretty good idea of how to take Apress © 2003 (928 and pages) advantage of the This VS .NET design-time support to develop databound Windows Form database text provides extensive coverage of ADO.NET technology applications. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

TheDataSet andnamespaces DataViewand components classes, and are how twotopowerful integrateand botheasy-to-use with components of the ADO.NET model.ADO.NET. In this section, you'll learn how to utilize DataSet and DataView components at design-time. In Chapter 4, we discuss their properties and methods in more detail and show how to use them programmatically. The DataSet and DataView components fall into the disconnected Table of Contents components category, which means you can use these components with or without data providers. We Applied ADO.NET—Building Data-Driven Solutions discuss disconnected data components in Chapter 3. Introduction Chapter 1

- ADO.NET Basics

Chapter 3


Understanding Typed DataSets Chapter 2 - Data Components in Visual Studio .NET in VS .NET There are two types of DataSets: typed and untyped. As discussed in Chapter 1 (and in more detail in - ADO.NET in Connected Environments Chapter 4), a typedDataSet has an XML schema attached to it. The XML schema defines members for Chapter 5 - Handling ADO.NET Events aDataSet corresponding to database table columns, and you can access data through these columns. Chapter 6 - Integrating XML with ADO.NET Untyped datasets are ones that are created at runtime and don't have a schema attached to them. In the Chapter 7 section, - Data Binding andyou Windows Forms Controls following we show how you can Data-Bound generate typed datasets using a VS .NET wizard. Chapter 4

Chapter 8


Chapter 9 - ADO.NET Exception Handling Generating Typed DataSets Using

a DataAdapter


As you 11 saw earlier,Procedures you can generate typed datasets by using the Generate Dataset option from a Chapter - Stored and Views DataAdapter's Properties dialog box..NET AndData as mentioned Chapter 12 - Oracle, SQLXML, and Other Providers earlier, the Generate DataSet option adds an XML schema to the project and also adds a class to the project inherited from the DataSet class. The designer looks like Figure 2-4. Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 13 - Developing a Custom Data Provider

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Figure 2-4: ADataSet's Properties window showing a typed DataSet


Again, you can see a typed DataSet's properties by right-clicking the DataSet and using the Properties menu option.



EveryDataSet generated by theSome IDE creates an XML schema for the DataSet. If you look at the bottom Appendix A - Relational Databases: Basic Concepts of the Properties window of SQL a DataSet, you'll see two links: View Schema and DataSet Properties. The Appendix B - Commonly Used Statements View Schema option Frequently lets you view the Questions DataSet schema, and the DataSet Properties hyperlink lets you Appendix C - ADO.NET Asked set the DataSet properties. By following these links you can also set the DataSet's column names and Index other properties. List of Figures List of Tables

Now you can use this DataSet as discussed earlier.

List of Listings

List of Sidebars Adding a Typed

DataSet

In the previous discussion, you saw how you can generate DataSet objects from a DataAdapter. There are also other ways to create a typed DataSet object. You can click the Project menu and choose Add New Item. This brings up the Add New Item window where you'll find the DataSet template (see Figure 2-5). The default name of the DataSet template is DataSet1.xsd, but you can change it by entering something in the Name text box.


ISBN:1590590732



- ADO.NET Basics

Chapter 2

- Data Components in Visual Studio .NET Figure Creating a typed DataSet from the Add New Item window Chapter 3 - 2-5: ADO.NET in Disconnected Environments Chapter 4


After adding the DataSet, the designer creates an XSD (XML Schema) file and adds it your project area. - Handling ADO.NET Events By default the schema is empty the first time you add a DataSet schema using the Add New Item. You Chapter 6 - Integrating XML with ADO.NET can see the contents of a DataSet schema by double-clicking DataSet1.xsd in the Solution Explorer. Chapter 7 - Data Binding and Windows Forms Data-Bound Controls As you can see from Figure 2-6, the designer has two options: the Server Explorer and the Toolbox. If you Chapter 8 Server - Constraints and Data Relations the Server Explorer. The XML designer has its own Toolbox, click the Explorer link, it launches Chapter 9 ADO.NET Exception Handling which contains various XML schema items. Chapter 5

Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index

Figure 2-6: EmptyDataset1.xsd in the VS .NET IDE


List The of next Listings step is to fill this XML schema with data and connect to a database. The easiest way to do this is

to use the Server Explorer. Open the Server Explorer by clicking the Sever Explorer link in the designer. List of Sidebars You can expand any database and simply drop a database object such as a table, a view, or a stored procedure on the designer from the Server Explorer. You can even drop multiple database objects. To keep it simple, drop only one table, the Employees table from the SQL Server Northwind database. Dragging the Employees table to the designer adds one XML schema (see Figure 2-7).


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Figure Designand viewData of the DataSet's XML schema Chapter 8 - 2-7: Constraints Relations Chapter 9


It also automatically adds the typed DataSet class that inherits from DataSet. If you go to the Class View, you can see the DataSet1 class. If you expand this class, you'll notice this class is derived from the Chapter 11 - Stored Procedures and Views DataSet class. You can explore the code added by the designer. However, you'll never use these class Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers members directly. Chapter 10 - Working with the ODBC .NET Data Provider


Chapter 14 -have Developing Web Once you a typedDatabase DataSet, youApplications can bind itusing to anyASP.NET data-bound control (as discussed earlier in this Chapter 15 - Using ADO.NET in Xml Web Services chapter). Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

Understanding the DataView


Chapter ADataView 19 - Mapped represents Objects: a view Performance of a DataSet Considerations object. and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

Question and Answer


Q: Why do I need a DataView when I can use a DataSet's DefaultViewManager?



Answers


A: List of Listings List of Sidebars

Actually, the DefaultViewManager provides a view of all the available tables in a DataSet. What if you want to display only one table? Or what if you want to filter or sort data?

ADataView provides you with Filter and Sort properties; by using them you can filter and sort the data. There are many occasions when you don't want all data from a table. You can apply a filter criteria on a DataView and bind the DataView to the data-bound controls. You can also separate multiple tables of a DataSet by associating each table with a DataViewl. For example, you can create a DataSet with three tables and create three different DataView objects for each table. Once you have a DataView object, you can attach it with any data-bound control, such as a DataGrid or a ComboBox control using the data-bound control's DataSource property. Or you can filter only records based on a

date or an ID.


ISBN:1590590732 by Mahesh and David Talbot Note In this chapter, weChand concentrate on the VS .NET part of DataView. We discuss the DataView Apress © 2003 (928in pages) class and its members more detail in Chapter 4.


Creating and attaching a DataView with a data source is classes, simple inand the designer. In this sample, you'll including ADO.NET internals, namespaces, and takes comprehensive look at XMLa DataView, though, you need to have a create and attachinterfaces, a DataView with aaDataSet. Before creating namespaces and classes, and how to integrate both with DataSet. ADO.NET.

First, you create a DataAdapter by simply dragging a database table from the Server Explorer to the form. This action adds a Connection and a DataAdapter to the application and makes them available Table of Contents at design-time. Second, you generate a DataSet from a DataAdapter by selecting the Generate Applied ADO.NET—Building Data-Driven Solutions Dataset menu option available after right-clicking the DataAdapter. Introduction

Chapter 1 need - ADO.NET Now you to addBasics a DataView. You simply drag a DataView by dragging the DataView control from Chapter 2Ø -Data Dataonto Components in Visual Studioadds .NETa DataView1 to the project. Toolbox your form. This action Chapter 3

- ADO.NET in Disconnected Environments Next, attach DataView1 to the DataSet. You can do that by simply setting the Table property of the Chapter 4 - ADO.NET in Connected Environments

DataView. The Table property of DataView1 lists the DataSet and DataSet tables. In this case, - Handling ADO.NET Events selectDataSet11.Employees as the Table property of DataView1 (see Figure 2-8).

Chapter 5 Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Figure 2-8: DataView Properties window


Appendix C - ADO.NET Frequently Asked Questions This is where the DataView is useful. The DataView has two properties: Sort and RowFilter. The Index Sort property takes an expression with the name of the column followed by the sort order. For example, if List Figures youofwant to sort data based on the FirstName column in ascending order, you set the FirstName ASC List string of Tables as the Sort property of DataView. List of Listings

TheRowFilter property filters the data of a DataView. This property works as a WHERE clause of the SELECT statement. The RowFilter property takes an expression with the column name and the criteria. For example, if you want to retrieve records where the country is USA, you simply set "Country='USA'" as the filter. As you can see in Figure 2-8, we set the RowFilter and Sort properties.

List of Sidebars

Note To sort in descending order, use DESC instead of ASC. Once you have a DataView, you can bind it to a data-bound control such as a DataGrid by setting databound control's DataSource property. To test this, you can drop a DataGrid control onto the form and setDataGrid'sDataSource property as DataView1. You can simply set that from the Properties window of DataGrid. Now if you compile and run your project, you'll only see USA records sorted on the FirstName column

(see Figure 2-9).


ISBN:1590590732


Table of Contents

Figure 2-9: Sorted and filtered data in a DataGrid Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions Using the Data Form Wizard by Mahesh Chand and David Talbot

ISBN:1590590732

The Data Form Wizard one (928 most useful tools for developing database applications. You can use the Data Apress is © 2003 pages) Form Wizard to develop your database application with and deleting capabilities. This is This text provides extensive coverage of viewing, ADO.NETupdating, technology probably the fastest way to develop database applications in .NET (unless you're an extremely fast typist!). including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces classes, andForm how to integrate bothawith In the following sections, you'lland use the Data Wizard to write fully functional database application including ADO.NET. features such as inserting, updating, and deleting data without writing a single line of code. In this simple example, you'll use the familiar Northwind database, and you'll use both the Customers and Orders tables to build a data relationship between table data. Table of Contents Applied ADO.NET—Building Data-Driven Solutions First, you'll create a Windows application. Second, you'll add a Data Form Wizard to it and then call the Data Introduction Form Wizard from the main application. Like many parts of this book, this topic is in the form of tutorial. Just Chapter 1 -simple ADO.NET Basics follow the steps, and in a few minutes you'll be able to run the application. Chapter 2 - Data Components in Visual Studio .NET Chapter Step 1: 3 Selecting - ADO.NET in a Disconnected Project Template Environments Chapter 4

- ADO.NET in Connected Environments Create 5a new Windows projectEvents by selecting File Ø New Project Ø Visual Basic Projects Ø Windows Application Chapter - Handling ADO.NET

and typing-MyDataFormWizardSamp as your application name. Integrating XML with ADO.NET

Chapter 6 Chapter 7

- Data Binding and Windows Forms Data-Bound Controls Step 2: Adding a Data Form Wizard Item

Chapter 8


Chapter 9 a- Data ADO.NET Handling Now add FormException Wizard by selecting Project Ø Add New Item Ø Data Form Wizard from the available Chapter 10 - You Working with the ODBC .NET Data Provider templates. can type DataForm1.vb as the name of your DataForm class in the Name field of the dialog box Chapter (see Figure 11 - 2-10). Stored (If Procedures you're using andC# Views language, the filename would be DataForm1.cs.) Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures

Figure 2-10: Adding a Data Form Wizard

List of Tables

List of click Listings Now Open, which calls the Data Form Wizard. List of Sidebars

Step 3: Walking through the Data Form Wizard The first page of the wizard is a welcome page telling you what the wizard is about to do.

Step 4: Choosing the DataSet You Want On the second page of the wizard, you can choose a DataSet name that will later be used to access the data. You can either create a new DataSet name or select an existing one. If there's no DataSet available in the project, the Use the Following Dataset Named option is disabled. For this test, type MyDS as the DataSet name in the Create a New Dataset Named option and move to the next page by clicking the Next button.

Step 5: Choosing a Data Connection

The next page ofApplied the wizard ADO.NET: asks youBuilding to provide Data-Driven a connection. Solutions The combo box displays your available connections. If you create a connection, use the New Connection ISBN:1590590732 button, which launches the Server by didn't Mahesh Chand and David Talbot Explorer discussed earlier in this You'll select the usual database, Northwind. If you followed the Server Apress © 2003 (928chapter. pages) Explorer discussion the provides beginning of this chapter, should have a Northwind connection in the list. If you Thisintext extensive coverageyou of ADO.NET technology don't have any connection including ADO.NET listed in this internals, list, create namespaces, a new connection classes, and using the Northwind SQL Server database. interfaces, and takes a comprehensive look at XML namespaces and or classes, and how to integrate both with Step 6: Choosing Tables Views ADO.NET.

The next page of the wizard lets you pick the tables and views you want to connect to the DataSet. As you can see in 2-11, we selected the Customers and Orders tables in the Available Items list on this page and use Table of Figure Contents the > button to add these tables to the Selected Items list. Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter Figure 17 - 2-11: Building Choosing Real-World tables Weband Applications views Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Now you're ready to create a relationship between these two tables.

Chapter 20 - COM Interoperability and ADO.NET Chapter 21 Creating - Messaging a Step 7:

Relationship between Tables


The nextApage of the wizard lets you define relationship between the Customers and Orders tables. It's useful Appendix - Relational Databases: Some BasicaConcepts to provide relationship between tables when you have a master-detail relationship in the database. In other Appendix B -a Commonly Used SQL Statements words, aCcustomer may have many orders associated with it, so there's a relationship through the CustomerID in Appendix - ADO.NET Frequently Asked Questions the Orders table joined to information about the customer in the Customers table. Now, say you want to see all Index theoforders of a customer based on the CustomerID. If you do this manually, you need to write code to select data List Figures from the Orders table to correspond to a CustomerID and then fill data to the form. If you use the Data Form Wizard instead, it does everything for you. Cool, huh?

List of Tables

List of Listings

List of is Sidebars This the same step you're going to see on the Create a Relationship between Tables page of the wizard.

You're going to create a relationship between the Customers and Orders tables based on the CustomerID. Name the relationship between the Customers and Orders table CustOrderRelation. You also need to pick the associated primary key and foreign key that links the parent to the child table. Once you've chosen the joining key (CustomerID), you have to press the > button to tell the wizard that you want to add it. When you run the final program, you'll see how you can filter all orders for a customer based on the CustomerID. As you can see from Figure 2-12, you need to pick one table as parent and another table as a child based on the relationship between them. In this example, the Customers table is the parent table, and the Orders table is the child table.


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7 - 2-12: Data Binding andCustomers Windows Forms Figure Selecting as theData-Bound parent andControls Orders as the child table to create the Chapter CustOrderRelation 8 - Constraints and Data relationship Relations Chapter 9



Step 8: Choosing Tables and Columns to Display on the Form


Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

The next page of the wizard lets you select which tables and columns you want to show on the form. For this

Chapter 13 select - Developing Custom from Data Provider example, all the acolumns both of the tables (this is the default selection). As you can see in Figure 2Chapter 14 Developing Database Web Applications using table ASP.NET 13, the Customers table is the master, and the Orders is the detail table. On this page, you can select Chapter 15 Using ADO.NET in Xml Web Services whatever column you want to display on the form. Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 2-13: Choosing columns to display on the Data Form Wizard

Step 9: Choosing the Display Style This page is an important part of creating your form. Actually, the Data Form Wizard adds a Form with some controls on it and writes code to fill, update, delete, and navigate data. There are two ways to view the data, and you choose your option on this page. These two options are as follows:

All Records in a Grid


byin Mahesh Chand and David Talbot Single Record Individual Controls

ISBN:1590590732


Figure 2-14 displays options.extensive coverage of ADO.NET technology This these text provides including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


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Figure 2-14: Choosing between a grid and individual controls on the Data Form Wizard



The output All Records in a Grid looks like Figure 2-15. After that you can resize or move the controls on the Chapter 13 - of Developing a Custom Data Provider form. 14 - Developing Database Web Applications using ASP.NET Chapter Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings

Figure 2-15: Grid DataForm output

List of Sidebars

The second option, Single Record in Individual Controls, shows data in text boxes and provides you with navigation controls. As you can see from Figure 2-16, the Single Record in Individual Controls option activates Add, Delete, Cancel, and Navigation Controls check boxes. You can uncheck these check boxes if you don't want to add those features to your project.


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Figure- 2-16: The Single Record in Individual Controls option Handling ADO.NET Events

Chapter 5 Chapter 6

- Integrating XML with ADO.NET The form generated by this option looks like Figure 2-17. As you can see, each column of the table has a field on

Chapter 7 - Data Binding and Windows Forms Data-Bound Controls the form. Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Figure Data Form Wizard-generated Appendix C - 2-17: ADO.NET Frequently Asked Questions form for the Single Record in Individual Controls option Index List of Figures

After selecting the data display style, click the Finish button. The Data Form Wizard adds the Windows form

List of Tables and the class DataForm1.vb corresponding to it. DataForm1 List of Listings List of Sidebars Step 10: Calling

the Data Form Wizard Form from the Application

Now you need to change one more thing. You need to call the DataForm1 form. Generally, you call a DataForm from a menu or a button click event handler. Say you've added two DataForm objects, DataForm1 andDataForm2, using both the options. The code in Listing 2-4 calls DataForm1. Listing 2-4: CallingDataForm1 from a Button Click Private Sub Button1_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button1.Click Dim dfw1 As DataForm1 = New DataForm1() dfw1.Show()

End Sub Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

Listing 2-5 calls DataForm2 This text provides from extensive a button click coverage handler. of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes comprehensive Listing 2-5: Calling DataForm2 froma a Button Clicklook at XML


Private Sub Button2_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button2.Click Table of Contents Dim dfw2 As DataForm2 = New DataForm2() Applieddfw2.Show() ADO.NET—Building Data-Driven Solutions Introduction End Sub Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3

- ADO.NET in Disconnected Environments Note have in modified the Environments name of your Data Form Wizard-generated form, you need to call that form Chapter 4 If- you ADO.NET Connected

of DataForm1 and DataForm2. Chapter 5 instead - Handling ADO.NET Events Chapter 6


Chapter 8


Step 11: the Chapter 7 - Viewing Data Binding andOutput Windows Forms Data-Bound Controls When you run any of the modes (DataGrid mode or individual column mode), you'll see Load and Update - ADO.NET Exception Handling buttons. The Load and Update buttons load and update the data, respectively, and Cancel All cancels all the Chapter 10 - Working with the ODBC .NET Data Provider operations. The neat thing is if you move into the top grid, corresponding information changes in the bottom grid. Chapter 9


Chapter After compiling 12 - Oracle, andSQLXML, running and yourOther application, .NET Data you'll Providers notice that without writing a single line of code, you just

created13a fully functional database application. Chapter - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

The Load button on the individual control form loads the data, and the Add, Update, and Delete buttons on the form inserts, updates, and deletes records, respectively.


Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

Data Form Wizard: Looking under the Hood



You just saw how you can develop fully functional database applications with the help of the Data Form Wizard. Now let's see what the wizard does for you in the actual code. (The inherent beauty of the VS .NET IDE is that it Chapter 21 - Messaging magically hides all the messy code for you.) The wizard adds two items to your project: MyDS.xsd and Chapter 22 - SQL Server and ADO.NET: Notes on Performance DataForm1.vb. Chapter 20 - COM Interoperability and ADO.NET


Understanding MyDS.xsd

Appendix C - ADO.NET Frequently Asked Questions Index MyDS.xsd is an XML schema for the DataSet you've added to the project. (It's similar to the one discussed in List Figures theof"Understanding Typed DataSets in VS .NET" section of this chapter.) List of Tables List of Listings

Understanding DataForm1.vb

List of Sidebars

The second item added by wizard is the DataForm1 class, a class derived from System.Windows.Forms.Form. The DataForm1 class defines the class's entire functionality: Public Class DataForm1 Inherits System.Windows.Forms.Form

ThebtnUpdate_Click and btnLoad_Click methods are the event handlers for the Update and Load buttons, respectively. As you can see from Listing 2-6, the btnLoad_Click method calls LoadDataSet, and thebtnUpdate_Click method calls the UpdateDataSet method.

Listing 2-6: The Load and Update Button Click Event Handlers


ISBN:1590590732

Private Sub btnUpdate_Click(ByVal sender As System.Object, _ Apress © 2003 (928 pages) ByVal e As System.EventArgs) Handles btnUpdate.Click This text provides extensive coverage of ADO.NET technology Try including ADO.NET internals, namespaces, classes, and 'Attempt to update the datasource. interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Me.UpdateDataSet() ADO.NET. Catch eUpdate As System.Exception 'Add your error handling code here. 'Display error message, if any. Table of Contents System.Windows.Forms.MessageBox.Show(eUpdate.Message) Applied ADO.NET—Building Data-Driven Solutions End Try Introduction Chapter 1

- ADO.NET Basics

End Sub Chapter 2 - Data Components in Visual Studio .NET Private Sub btnLoad_Click(ByVal sender As System.Object, _ Chapter 3 - ADO.NET in Disconnected Environments ByVal e As System.EventArgs) Handles btnLoad.Click ChapterTry 4 - ADO.NET in Connected Environments Chapter 5 'Attempt - Handling to ADO.NET loadEvents the dataset. Chapter 6 Me.LoadDataSet() - Integrating XML with ADO.NET ChapterCatch 7 - Data Binding Windows Forms Data-Bound Controls eLoad Asand System.Exception Chapter 8 'Add - Constraints and Data Relations code here. your error handling Chapter 9 'Display - ADO.NET error Exception message, Handling if any. System.Windows.Forms.MessageBox.Show(eLoad.Message) Chapter 10 - Working with the ODBC .NET Data Provider End Try Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

TheLoadDataSet method loads the data from the data source into the controls by calling FillDataSet (see Listing 2-7). As you can see from the code, it assigns the MyDS DataSet generated by the Data Form Wizard as Chapter 16 - ASP.NET Server Controls and Data Binding a temporary DataSet and fills it using the FillDataSet method. Chapter 15 - Using ADO.NET in Xml Web Services

Chapter 17 - Building Real-World Web Applications

Chapter - Object-Relational in .NET Listing18 2-7: LoadDataSet Mapping Method Generated by the Data Form Wizard Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Public Sub LoadDataSet() 'Create a new dataset to hold the records returned Chapter'A 22 temporary - SQL Server and ADO.NET: Performance dataset is Notes usedonbecause filling the existing dataset would Appendix A Relational Databases: Some Basic Concepts 'require the databindings to be rebound. Appendix B -objDataSetTemp Commonly Used SQL As Statements Dim MyDataFormWizardSamp.MyDS Appendix C - ADO.NET Frequently Asked Questions objDataSetTemp = New MyDataFormWizardSamp.MyDS() Index Try List of Figures 'Attempt to fill the temporary dataset. Me.FillDataSet(objDataSetTemp) List of Tables Catch List of Listings eFillDataSet As System.Exception 'Add your error handling code here. List of Sidebars Throw eFillDataSet End Try Try 'Empty the old records from the dataset. objMyDS.Clear() 'Merge the records into the main dataset. objMyDS.Merge(objDataSetTemp) Catch eLoadMerge As System.Exception 'Add your error handling code here. Throw eLoadMerge End Try End Sub Chapter 21 - Messaging


ISBN:1590590732

Apress © 2003 (928 pages) TheFillDataSet fills the DataSet from the DataAdapter by calling the Fill method on each DataAdapter. Note This text that provides with the extensive Data Form coverage Wizard,ofa ADO.NET DataAdapter technology is created for each table-one including ADO.NETtable internals, namespaces, classes,for and DataAdapter for the Customers and one DataAdapter the Orders table. Both DataAdapters fill interfaces, and takes a comprehensive look at XML the same DataSet. Listing 2-8 shows the FillDataSet method. namespaces and classes, and how to integrate both with ADO.NET.

Listing 2-8: The FillDataSet Method Generated by the Data Form Wizard Table of Contents

Public Sub FillDataSet(ByVal dataSet As MyDataFormWizardSamp.MyDS)

Applied'Turn ADO.NET—Building Data-Driven Solutions before the dataset is filled. off constraint checking Introduction 'This allows the adapters to fill the dataset without concern Chapter'for 1 - ADO.NET Basics dependencies between the tables. ChapterdataSet.EnforceConstraints 2 - Data Components in Visual Studio = .NET False Chapter Try 3 - ADO.NET in Disconnected Environments Chapter 4 'Open - ADO.NET thein connection. Connected Environments Chapter 5 Me.OleDbConnection1.Open() - Handling ADO.NET Events

the dataset through the OleDbDataAdapter1. Chapter 6 'Attempt - Integratingto XMLfill with ADO.NET Chapter 7 Me.OleDbDataAdapter1.Fill(dataSet) - Data Binding and Windows Forms Data-Bound Controls Chapter 8 Me.OleDbDataAdapter2.Fill(dataSet) - Constraints and Data Relations

fillException As System.Exception Chapter Catch 9 - ADO.NET Exception Handling 'Add your error handling code here. Throw fillException 11 - Stored Procedures and Views Finally 12 - Oracle, SQLXML, and Other .NET Data Providers 'Turn constraint checking back on. 13 - Developing a Custom Data Provider dataSet.EnforceConstraints = True 14 - Developing Database Web Applications using ASP.NET 'Close the connection whether or not the exception was thrown. 15 Me.OleDbConnection1.Close() - Using ADO.NET in Xml Web Services 16 Server Controls and Data Binding End- ASP.NET Try

Chapter 10 - Working with the ODBC .NET Data Provider Chapter Chapter Chapter Chapter Chapter Chapter

Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET End Sub Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

Note youand may notice isNotes that the Form Wizard uses the OleDb provider to write the Data Form Chapter 22 One - SQLthing Server ADO.NET: on Data Performance code. Appendix A Wizard - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

TheUpdateDataSource method updates the data source from the DataSet. This method is called by the

Appendix C - ADO.NET Frequently Asked Questions UpdateDataSet method and utilizes the Update command of the DataAdapters. Listing 2-9 shows the Index UpdateDataSource method. List of Figures

Listing 2-9: The UpdateDataSource and UpdateDataSet Methods Generated by the Data Form Wizard List of Tables List of Listings List ofPublic Sidebars Sub UpdateDataSet()

'Create a new dataset to hold the changes that have been made to the main dataset. Dim objDataSetChanges As MyDataFormWizardSamp.MyDS = _ New MyDataFormWizardSamp.MyDS() 'Stop any current edits. Me.BindingContext(objMyDS, "Customers").EndCurrentEdit() Me.BindingContext(objMyDS, "Orders").EndCurrentEdit() 'Get the changes that have been made to the main dataset. objDataSetChanges = CType(objMyDS.GetChanges, MyDataFormWizardSamp.MyDS) 'Check to see if any changes have been made. If (Not (objDataSetChanges) Is Nothing) Then Try

'There are changes that need to be made, so attempt to update" Applied ADO.NET: Data-Driven Solutions 'calling the updateBuilding method and passing the dataset and any parameters. ISBN:1590590732 by Mahesh Chand and David Talbot Me.UpdateDataSource(objDataSetChanges) Apress © 2003 (928 pages) objMyDS.Merge(objDataSetChanges) This text provides extensive coverage of ADO.NET technology objMyDS.AcceptChanges() including ADO.NET internals, namespaces, classes, and Catch eUpdate As System.Exception interfaces, and takes a comprehensive look at XML 'Add namespaces your error codeto here. and handling classes, and how integrate both with ThrowADO.NET. eUpdate End Try 'Add your code to check the returned dataset for any errors" Table of Contents 'pushed into the row object's error. AppliedEnd ADO.NET—Building Data-Driven Solutions If Introduction End Sub Chapter 1

- ADO.NET Basics

Chapter Public 2 Sub - Data UpdateDataSource(ByVal Components in Visual Studio .NET ChangedRows As MyDataFormWizardSamp.MyDS) ChapterTry 3 - ADO.NET in Disconnected Environments

data insource only needs to be updated if there are changes pending. Chapter 4 'The - ADO.NET Connected Environments (Not (ChangedRows) Chapter 5 If- Handling ADO.NET Events Is Nothing) Then Chapter 6

theXML connection. -'Open Integrating with ADO.NET

Chapter 7

-Me.OleDbConnection1.Open() Data Binding and Windows Forms Data-Bound Controls

'Attempt to update the data source. OleDbDataAdapter1.Update(ChangedRows) Chapter 9 - ADO.NET Exception Handling OleDbDataAdapter2.Update(ChangedRows) Chapter 10 - Working with the ODBC .NET Data Provider End If Chapter 11 - Stored Procedures and Views Catch updateException As System.Exception Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers 'Add your error handling code here. Chapter 13 - Developing a Custom Data Provider Throw updateException ChapterFinally 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services 'Close the connection whether or not the exception was thrown. Chapter 16 ASP.NET Server Controls and Data Binding Me.OleDbConnection1.Close() ChapterEnd 17 -Try Building Real-World Web Applications Chapter End Sub 18 - Object-Relational Mapping in .NET Chapter 8


Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

ThebtnCancelAll_Click method is the Cancel All button click handler, which calls the DataSet's RejectChanges method (see Listing 2-10).

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Listing 2-10: Cancel All Button Click Event Handler


Private Sub btnCancelAll_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles btnCancelAll.Click List of Tables Me.objMyDS.RejectChanges() List of Listings End Sub List of Figures

List of Sidebars

Summary


ISBN:1590590732

Congratulations! Apress You've©now 2003completed (928 pages) one more step toward understanding ADO.NET and its components. After completing this extensive chapter, you should a good idea of how to write database This text provides coverage of have ADO.NET technology applications usingincluding the VS .NET IDE. ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and components how to integrate both with The Server Explorer is a handy In this chapter, you learned about visual data in VS .NET. ADO.NET. utility added to VS .NET IDE to help you manage your database connections.

DataAdapters let you connect to a data source at design-time and populate DataSet objects. In

Table of Contents addition, DataAdapters also allow you to add, update, and delete data through data command objects. Applied ADO.NET—Building Data-Driven Solutions The VS .NET IDE also lets you generate typed DataSets, which are DataSets with properties of tables Introduction and columns specific to a data source. Chapter 1 - ADO.NET Basics

ADataView is a Components bindable view a DataSet. You can sort and filter a DataSet with a DataView and Chapter 2 - Data in of Visual Studio .NET use it to3 bind to a graphical component in many of the Windows form controls. Chapter - ADO.NET in Disconnected Environments Chapter 4


Finally, the Data Form Wizard is a useful tool for generating full-fledged database applications with - Handling ADO.NET Events features such as inserting, deleting, and updating in no time.

Chapter 5 Chapter 6


Chapter 7 -chapter, Data Binding and Windows Forms Data-Bound classes Controls and components. In the next we discuss ADO.NET disconnected Chapter 8 - Constraints and Data Relations Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 3: ADO.NET in Disconnected Environments ISBN:1590590732 by Mahesh Chand and David Talbot

Overview


This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and In Chapter 1 and Chapter interfaces, 2,and youtakes learned a comprehensive about ADO.NET, look and at XML you learned how to use ADO.NET and classes, how to learned integratehow bothtowith components withnamespaces Visual Studio (VS) .NET.and You also write code that binds ADO.NET ADO.NET.

components to data-bound controls and how to use VS .NET's Integrated Development Environment (IDE) wizards to write full-fledged database applications. Table of Contents

In this chapter, you'll get a broad view of the ADO.NET architecture and the basic building blocks of ADO.NET in a disconnected environment. Now, the first question on your mind might be, "What is a Introduction disconnected environment?" Generally, when we talk about ADO.NET and data access, we're talking Chapter 1 - stored ADO.NET about data in aBasics database server such as a SQL Server or Oracle. Actually, ADO.NET not only Chapter 2 a-way DatatoComponents in Visual Studio provides work with databases, it also.NET allows you to access various kinds of data sources and even Chapter 3 - representations ADO.NET in Disconnected Environments in-memory of data. In-memory data is stored in a system's memory and erased when an Chapter 4 - is ADO.NET Connected Environments application closed. in Data that is held in-memory is referred to as a disconnected environment. Applied ADO.NET—Building Data-Driven Solutions

Chapter 5

- Handling ADO.NET Events Why use data? there may be occasions when you don't want to store data in a database Chapter 6 in-memory - Integrating XML Well, with ADO.NET

but you7want to perform actionsForms such as adding, deleting, Chapter - Data Binding some and Windows Data-Bound Controlssorting, and searching data, and once you're done, you don't care what happens to the data. This scenario would be perfect for working with - Constraints and Data Relations disconnected data.

Chapter 8 Chapter 9


Chapter 10 In - Working .NET Data Note Chapter with 4, wethe willODBC concentrate onProvider working with connected data, where data will be stored in a Chapter 11 database. - Stored Procedures and Views In the connected environment, you use a data provider to connect to a database and Chapter 12 read - Oracle, Other Providers and SQLXML, write dataand using the.NET dataData provider classes. Chapter 13 - Developing a Custom Data Provider

ADO.NET classes Web are basic buildingusing blocks of the ADO.NET architecture. The classes are Chapter 14 disconnected - Developing Database Applications ASP.NET independent of data providers andWeb dataServices sources. In other words, you can use these classes with data Chapter 15 - Using ADO.NET in Xml providers as well as without data providers.

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 -data Building Real-World Web ADO.NET providers are sets ofApplications classes designed to work with multiple data sources to provide the Chapter Object-Relational Mapping in .NET ADO.NET provides many data providers to work with best of 18 all -the database access technologies. Chapter 19kinds - Mapped Objects: Performance Considerations different of data sources, including OleDb, ODBC,and andData Sql.Binding Chapter 20 - COM Interoperability and ADO.NET

Note can access SQL Server 6.5 or previous versions using ODBC or OleDb data providers. Chapter 21 You - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Although ADO.NET is a new programming model, it still uses old native data access technologies to access different data sources. For example, OleDb data providers use the native OLE DB Application Appendix B - Commonly Used SQL Statements Programming Interface (API) to access OLE DB data sources. Similar to OLE DB data sources, ODBC Appendix C - ADO.NET Frequently Asked Questions data providers use ODBC drivers and the ODBC Administration to access ODBC data sources. ADO.NET Index data providers wrap up these technologies for easier programming. Appendix A - Relational Databases: Some Basic Concepts

List of Figures

So,ofwhat's List Tablesnew in ADO.NET? That is a good question. Weren't you using the ODBC and OLE DB APIs in previous data access technologies? You're right. ADO.NET uses the same native API. The only difference List of Listings is, of ADO.NET List Sidebars provides high-level, object-oriented classes that are easy to program and understand. Further, all the data providers supply the same programming model. So, if you know how to write applications using OleDb data providers, you'll be able to write applications using ODBC or Sql providers in no time. It's just a matter of changing the class names and connection strings. When working with SQL Server databases, the Sql data provider is much more efficient and faster in comparison to the OleDb or ODBC data providers. Unlike ODBC and OleDb data providers, which use ODBC and OLE DB data layers to connect to a SQL Server database, the Sql data provider uses the native SQL Server layer to connect to the databases. We discuss this in more detail in later chapters.

Appliedthe ADO.NET: BuildingArchitecture Data-Driven Solutions Understanding ADO.NET by Mahesh Chand and David Talbot

ISBN:1590590732

You briefly lookedApress at the©ADO.NET architecture in Chapter 1. Now you'll see a broad view of the ADO.NET 2003 (928 pages) architecture and learn how disconnected andcoverage connected components (classes) provide access to multiple This text provides extensive of ADO.NET technology data sources. In this section, we talk about objects in general. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML and classes,ofand to integrate both Figure 3-1 showsnamespaces the basic architecture thehow ADO.NET model. Aswith you can see, the entire ADO.NET ADO.NET. model sits between the data source and client applications that can be built using Windows Forms, Web Forms, or even console-based applications. The Connection is the first component that talks to a data source. In ADO.NET, each data provider (OleDb, Sql, Odbc, or Oracle) has its own Connection class. Table of Contents TheConnection component is a mediator between a DataAdapter or a Command component. The Applied ADO.NET—Building Data-Driven Solutions DataAdapter components create SQL INSERT,SELECT,UPDATE, and DELETE statements that add, Introduction read, update, and delete data from a data source, respectively. Not only does a DataAdapter create Chapter 1 - ADO.NET Basics these SQL statements, it also executes these statements. Basically, a DataAdapter (with the help of Chapter 2 -physically Data Components Visual Studio Command) updatesinand reads data.NET from a data source. In Figure 3-1, an arrow shows this flow Chapter 3 ADO.NET in Disconnected Environments of data. Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - 3-1: Relational Databases: Some Basic Concepts Figure ADO.NET architecture Appendix B - Commonly Used SQL Statements

You canCuse the Command components with or without a DataAdapter. You can directly execute Appendix - ADO.NET Frequently Asked Questions commands and read data in a DataReader, which provides a read-only, forward-only fast access to data. Index This best when you need to read data in applications that are not data-bound. You can also see from List of is Figures Figure 3-1 that all arrows are double-sided arrows except the arrow connecting a DataReader and List of Tables Command. A double-sided arrow means data transfer is possible on both sides. A DataReader can only List of Listings read data, which is why the DataReader has only a one-sided arrow. This shows that you can fill a DataReader from the Command, but you can't send back data from a DataReader to the Command.

List of Sidebars

ADataAdapter sits between a data source and a DataSet. It provides Fill and Update methods to fill a DataSet from a data source based on the SELECT statement, and the Update method saves a DataSet's changes to the data source. The DataSet plays a vital role in data-bound Graphical User Interface (GUI) applications to display and manipulate data. Not only does it provide fast data manipulation using Extensible Markup Language (XML) schemas, it also provides multiple views of data that can be bound with multiple Windows Forms and Web Forms data-bound controls. ADataSet is a collection of DataTable components. A DataTable represents a table in a data source. You can apply a filter or do sorts on a table. You can bind a DataTable to data-bound controls such as a DataGrid,DataList,ListBox, or ComboBox using DataView. You can also apply sorts and filters on

aDataView. As you can see from Figure 3-1, there are three DataSets represented and three Applied ADO.NET: Building Data-Driven Solutions DataTables. Each DataTable binds to different data-bound controls using different DataViews. by Mahesh Chand and David Talbot

ISBN:1590590732

2003 (928 pages) This section gaveApress you an© overview of the ADO.NET architecture. We discuss these controls in more detail throughout this chapter and Chapter 4, depending on of their category. This text provides extensive coverage ADO.NET technology

including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Solutions Exploring the ADO.NET ClassData-Driven Hierarchy by Mahesh Chand and David Talbot

ISBN:1590590732

Before you start swimming in the Apress © 2003 (928 deep pages) ocean of ADO.NET, you need to take a quick look at the ADO.NET class hierarchy provided by the .NET Runtime Class Library (alsotechnology known as Base Class Library, or BCL). This text provides extensive coverage of ADO.NET These classes represent ADO.NET components. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and.NET classes, and how to integrate with in three general namespaces and All ADO.NET functionality in the Runtime Class Library isboth defined ADO.NET. a number of provider-specific namespaces. System.Data and System.Data.Common are two general namespaces common to all data providers. The System.Data.SqlTypes namespace is a SQL Serverspecific namespace. The remainder of the functionality is defined in the data provider-specific Table of Contents namespaces; some of them are System.Data.OleDb,System.Data.ODBC, and Applied ADO.NET—Building Data-Driven Solutions System.Data.SqlClient. Introduction

Chapter 1 - ADO.NETnamespace Basics TheSystem.Data defines classes that you can use with all the data providers or without Chapter 2 - Data in Visual Studio .NET interfaces that are base classes for the data provider data providers at Components all. This namespace also defines Chapter classes. 3Figure - ADO.NET 3-2 shows in Disconnected the System.Data Environments namespace's class hierarchy. Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List ofFigure Tables 3-2: TheSystem.Data namespace class hierarchy List of Listings

The namespace defines classes common to all data providers. Figure 3-3 shows List ofSystem.Data.Common Sidebars theSystem.Data.Common namespace hierarchy.


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Figure 3-3: TheSystem.Data.Common namespace hierarchy


TheSystem.Data.SqlTypes defines classes for native SQL Server data types that provide Chapter 12 - Oracle, SQLXML, and namespace Other .NET Data Providers type-safe the .NET data types and the SQL Server native data types. Figure 3-4 Chapter 13 conversion - Developingbetween a Custom Data Provider shows the System.Data.SqlTypes namespace hierarchy.

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 3-4: TheSystem.Data.SqlTypes namespace hierarchy In addition to these three namespaces, there are a number of provider-specific namespaces. The class hierarchy models of these namespaces are similar except for the name of the class. The classes defined

in the provider-specific namespaces start with the data provider name. For example, the Sql data provider ADO.NET: Building Data-Driven classes start withApplied Sql, and the OleDb data provider classesSolutions start with OleDb. The Command object class ISBN:1590590732 by Mahesh Chand and David Talbot of the Sql data provider is SqlCommand, and the Command object class of the OleDb data provider is Apress © 2003 (928 pages) OleDbCommand. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, namespace classes, and class hierarchy because all the data In this section, you'll see only the System.Data.OleDb interfaces, and takes a comprehensive look at XML providers (including System.Data.Sql and System.Data.Odbc) implement the same class hierarchy namespaces and classes, and how to integrate both with model (with minorADO.NET. changes). Figure 3-5 shows the System.Data.OleDb namespace hierarchy.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Figure TheObjects: System.Data.OleDb namespaceand hierarchy Chapter 19 - 3-5: Mapped Performance Considerations Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

We discuss these namespaces and their classes in more detail throughout this chapter and Chapter 4.


Building Data-Driven Solutions Choosing aApplied DataADO.NET: Provider by Mahesh Chand and David Talbot

ISBN:1590590732

As you saw earlier, many data(928 providers Apress © 2003 pages) are available in ADO.NET. There may be cases when you can access a data source using more one data provider. Now thetechnology question arises: Which one is better? This text providesthan extensive coverage of ADO.NET When choosing aincluding data provider, the main criteria of selection is performance and multiple data source ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML connectivity. namespaces and classes, and how to integrate both with ADO.NET. In brief, to work with SQL Server 7 or later databases, the Sql data provider is the best choice. The Sql

data provider bypasses many layers and directly connects to the internal layer of the infrastructure. Not only that, but the Sql data provider provides classes that help you to convert from native SQL Server data Table of Contents types to the .NET data types, and vice versa. Applied ADO.NET—Building Data-Driven Solutions

Introduction OleDb data provider uses native OLE DB providers to access OLE DB data sources. OleDb data providers Chapter 1 -because ADO.NETsome Basicsdatabase providers don't implement ODBC drivers to connect to a database are useful Chapter - Data Components in Visual Studio .NET through2 ODBC. Chapter 3

- ADO.NET in Disconnected Environments The Odbc provider provides aEnvironments way to work with different kinds of data sources through ODBC drivers. Chapter 4 -data ADO.NET in Connected

ODBC 5is an older data accessEvents technology, but many applications still use ODBC to access data sources. Chapter - Handling ADO.NET ODBC data providers provide a way to access ODBC data sources through ODBC drivers and ODBC - Integrating XML with ADO.NET Administration. Database venders generally provide the ODBC drivers. Using ODBC you can access any Chapter 7 - Data Binding and Windows Forms Data-Bound Controls data source for which you have an ODBC driver installed. Chapter 6 Chapter 8


Chapter 9 - Odbc ADO.NET In general, dataException provider Handling connectivity is faster than OLE-DB because of OLE DB's COM nature, Chapter - Working with ODBC .NET is Data Provider which is10very "chatty." Sqlthe data provider faster than ODBC to work with SQL Server databases. But Chapter - Stored Procedures and ODBC 11 is useful when you need to Views write a generic class that can access multiple data sources through Chapter ODBC.12 For- Oracle, example, SQLXML, say you're and Other writing.NET an application Data Providers that can work with multiple back-end servers

including Server, Oracle, Access, and MySql. When you install these back-end servers, you also Chapter 13 SQL - Developing a Custom Data Provider install the driverDatabase for theseWeb databases. So, you can write a generic application that accesses these Chapter 14 ODBC - Developing Applications using ASP.NET data sources based on the in ODBC DataServices Source Name (DSN). You can also pass the driver and data Chapter 15 - Using ADO.NET Xml Web source 16 information the application itself, butBinding the user has to only create a DSN from ODBC, and the Chapter - ASP.NETinServer Controls and Data application use Real-World that DSN as theApplications connection string in the application for the Odbc data provider. Chapter 17 - can Building Web Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

AppliedADO.NET ADO.NET: Building Data-Driven Solutions Understanding Disconnected Classes by Mahesh Chand and David Talbot

ISBN:1590590732

ADO.NET disconnected the basic building blocks of the ADO.NET architecture. These classes Apress ©classes 2003 (928are pages) loosely couple with data providers. The System.Data defines these classes. This text provides extensive coverage of namespace ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

The System.Data Namespace

TheSystem.Data namespace consists of classes that are the basic building blocks of the ADO.NET architecture. These classes are also known as disconnected classes because they store disconnected Table Contents dataof and can work without data providers. Applied ADO.NET—Building Data-Driven Solutions

Table 3-1 describes some of the common classes of the System.Data namespaces. We discuss these Introduction classes1in -more detailBasics throughout this chapter. Chapter ADO.NET Chapter 2


Chapter 3


Table 3-1: The System.Data Namespace Classes

Chapter 4 - ADO.NET in Connected Environments CLASS DESCRIPTION Chapter 5


Constraint, Constraints are rules set on a database table and its - Integrating XML with ADO.NET ConstraintCollection, columns to help maintain the integrity of the data or to Chapter 7 - Data Binding and Windows Forms Data-Bound Controls UniqueConstraint, enforce business rules. The Constraint class object Chapter 8 - Constraints and Data Relations ForeignKeyConstraint represents a constraint that you can apply on a Chapter 9 - ADO.NET Exception Handling DataColumn object. Some of these constraints are Chapter 10 - Working with the ODBC .NET Data Provider primary key, uniqueness, and foreign key. The Chapter 11 - Stored Procedures and ViewsConstraintCollection class represents a collection of Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers constraints for a DataTable.UniqueConstraintand Chapter 13 - Developing a Custom Data Provider ForeignKeyConstraint represent unique and foreign Chapter 14 - Developing Database Web Applications using ASP.NET key constraints. Chapter 6


TheDataColumn object represents a column of a table. DataColumnCollection represents a collection of Chapter 17 - Building Real-World Web Applications columns of a table. DataColumn, DataColumnCollection

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 18 - Object-Relational Mapping in .NET

DataRelation, DataRelation object represents a parent/child Chapter 19 - Mapped Objects: PerformanceThe Considerations and Data Binding DataRelationCollection relationship between two DataTable objects. Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

DataRelationCollection represents a collection of

DataRelation. Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts DataRow, DataRowCollection ADataRow object represents a row of a table, and Appendix B - Commonly Used SQL Statements DataRowCollection represent a collection of rows. Appendix C - ADO.NET Frequently Asked Questions

DataRowView

Index

List of Figures List of Tables ListDataSet of Listings List of Sidebars

DataRowView represents a view of DataRow. It's useful when you want to attach a DataRow with data-bound controls such as a DataGrid. In ADO.NET, a DataSet object is a replacement of the ADO recordset and represents an in-memory cache of data. A DataSet is a collection of DataTableobjects.

DataTable, DataTableCollection

ADataTable object represents an in-memory cache of a table, and DataTableCollection is a collection of one or more DataTable objects.

DataView

Represents a data-bindable, customized view of a DataTable for sorting, filtering, searching, editing, and navigation.

DataViewManager

TheDefaultViewManager represents the default view of aDataSet or DataTableCollection.

TheSystem.Data namespace also defines many enumerations and delegates that we discuss Applied ADO.NET: Building Data-Driven Solutions throughout this chapter. by Mahesh Chand and David Talbot

ISBN:1590590732

Once you have an Apress idea © of2003 what (928 classes pages) the System.Data.Common namespace constaints, you'll have no problem understanding how to useextensive these classes in aofsample application. This text provides coverage ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

The System.Data.Common Namespace

As its name says, the System.Data.Common namespace contains classes shared by the .NET data providers. Some of these classes are the base classes for the .NET data provider classes. Table 3-2 Table of Contents defines some of these classes. Applied ADO.NET—Building Data-Driven Solutions Introduction Table 3-2: The System.Data.Common Namespace Classes Chapter 1 - ADO.NET Basics

CLASS DESCRIPTION Chapter 2 - Data Components in Visual Studio .NET Chapter 3 - ADO.NET in Disconnected Environments DataAdapter TheDataAdapter class represents a DataAdapter Chapter 4 - ADO.NET in Connected Environments that works as a bridge between a data source and Chapter 5


Chapter 6 Chapter 7

- Integrating XML with ADO.NET methods. The Fill method fills data from a data source - Data Binding and Windows Forms toData-Bound a DataSetControls using Command objects. This class is a

Chapter 8

- Constraints and Data Relations base class for the DbDataAdapter class, which itself is

DataSet. It implements the Fill and Update

a base class for the OleDbDataAdapter, SqlDataAdapter, and ODBC DataAdapter classes. Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views These classes are discussed in the "The DataAdapter: to Your Environment" section of Chapter 4. Chapter 12 - Oracle, SQLXML, and Other .NETAdapting Data Providers Chapter 9


Chapter 13 - Developing a Custom Data Provider DataColumnMapping If you don't want to use the default column names of a Chapter 14 - Developing Database Web Applications ASP.NET table tousing access these columns, you can define your own Chapter 15 - Using ADO.NET in Xml Web Services names. You map your custom names with the original Chapter 16 - ASP.NET Server Controls and Data column Binding names through DataAdapters and use these

names in your application. The SourceColumn and Chapter 17 - Building Real-World Web Applications DataSetColumnproperties of this class represent the Chapter 18 - Object-Relational Mapping in .NET source column name DataSet column name. Chapter 19 - Mapped Objects: Performance Considerations and Data and Binding Chapter 20 - COM Interoperability and ADO.NET DataColumnMappingCollection Collection of DataColumnMapping objects. Chapter 21 - Messaging

DataTableMapping can even map a database table to a DataTable Chapter 22 - SQL Server and ADO.NET: NotesYou on Performance and use this DataTable as the source in your Appendix A - Relational Databases: Some Basic Concepts

applications. The ColumnMappings property returns DataColumnMappingCollection for the Appendix C - ADO.NET Frequently Asked Questions DataTable. The DataSetTable and SourceTable Index properties represent the DataTable and source tables. Appendix B - Commonly Used SQL Statements

List of Figures

ListDataTableMappingCollection of Tables List of Listings

Collection of DataTableMapping objects.

DbDataAdapter

Inherited from DataAdapter, this class implements the IdbDataAdapter interface. This class is used as the base class of a data provider's DataAdapterclasses.

DBDataPermission

Ensures that data providers have security to access data. This class is a base class from the OleDbDataPermission,OdbcDataPermission, andSqlDataPermission classes.

List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions Working with DataTables by Mahesh Chand and David Talbot

ISBN:1590590732

ADataTable object represents database table. A data table is a collection of columns and rows. The Apress © 2003 (928apages) DataRow object This represents a table row, andcoverage the DataColumn object represents a column or a field of the text provides extensive of ADO.NET technology table. Assuming you haven't imported, reengineered, or otherwise "inherited" a database and its including ADO.NET internals, namespaces, classes, and takes a with comprehensive at XML DataTables, theinterfaces, first step and to working these threelook objects is to create a DataTable schema, which is namespaces and classes, and how to integrate defined by the DataColumnCollection object. You use theboth Addwith method of DataColumnCollection ADO.NET. to add columns to the collection. The Columns property of the DataTable object represents the DataColumnCollection, which is a collection of DataColumn objects in a DataTable. You use a DataRow object to add data to a DataTable. The DataRowCollection object represents a collection Table of Contents of rows of a DataTable Data-Driven object, which can be accessed by its Rows property. Applied ADO.NET—Building Solutions Introduction

Figure 3-6 shows the relationship between the DataTable, the DataRow, and the DataColumn.

Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Figure 3-6: Relationship between the DataTable, the DataRow, and the DataColumn


A database table schema is the structure or design of the table, which includes table columns, their types,

Chapter 21 - Messaging relationships, and constraints. You can view a database schema from the Server Explorer as well as from Chapter 22 - SQL Server and ADO.NET: on Performance other places such as the SQL Server Notes Enterprise Manager or Visio. To view a table schema from the Appendix A - Relational Databases: BasicinConcepts Server Explorer, simply right-clickSome the table the Server Explorer and then click the Design Table menu Appendix B - see Commonly Used SQL Statements item. You'll the Column Name, Data Type, Length, and Allow Nulls columns. These columns Appendix C the - ADO.NET Frequently Asked Questions represent name, data type, length, and whether the column allows null values, respectively. The Index Columns area represents the properties of a column; you can see and specify the description, default

value, formula if any, and other properties of a column. List of Figures List of Tables

Note A database table column is also called a field.

List of Listings

List Sidebars So,ofwhen we talk about creating a DataTable, we mean building a database table (in memory, of

course) and its schema using the DataTable and the DataColumn objects. Based on a column requirement, you can also apply constraints on a column. A constraint is a rule that restricts adding unwanted data to a column. For example, the uniqueness of a column means that a column can't have duplicate values. You'll see constraints in more detail in Chapter 8. After creating a data table schema, the next step is to add DataRows to the DataTable. You use DataRows using the DataRow object. A DataRow object represents a row in a table. Tip To see data in the Customers table, double-click the Customers table in the Server Explorer. OK, now you'll learn how to accomplish this task in ADO.NET using the DataTable,DataColumn, and DataRow objects. First we discuss the DataColumn and the DataRow objects, followed by the DataRelation and the DataTable objects. Then, you'll create a sample project containing all these

objects to build a DataTable and add data to it programmatically.


The DataColumn Apress © 2003 (928 pages)

ISBN:1590590732

text provides extensive coverage of ADO.NET technology To understand a This DataTable, you must first understand DataRows and DataColumns. As you can see including ADO.NET internals, namespaces, classes, and fromFigure 3-6, the DataColumnCollection type returns collection of columns that you can access interfaces, and takes a comprehensive look at aXML through the Columns property of classes, the DataTable. namespaces and and how to integrate both with ADO.NET.

TheDataColumnCollection object represents a collection of columns attached to a DataTable. You add a DataColumn to the DataColumnCollection using its Add method. The DataColumn object Table of Contents represents a column of a DataTable. For example, say you want to create a Customers table that Applied ADO.NET—Building Data-Driven Solutions consists of three columns: ID, Address, and Name. So, you create three DataColumn objects and add Introduction these columns to the DataColumnCollection using the DataTable.Column.Add method. Chapter 1

- ADO.NET Basics

TheDataColumn has some properties. These properties describe a column, such as its uniqueness, Chapter 2 - Data Components in Visual Studio .NET what kind of data you can store in that column, its default value, its caption, its name, and so on. Table 3-3 Chapter 3 - ADO.NET in Disconnected Environments describes some of the DataColumn class members. Chapter 4 - ADO.NET in Connected Environments Chapter 5


Chapter 6


Table 3-3: The DataColumn Class Properties

Chapter 7 - Data Binding and DESCRIPTION Windows Forms Data-Bound Controls PROPERTIES Chapter 8 - Constraints and Data Relations

AllowDBNull Both read and write; represents whether the column can store null - ADO.NET Exception Handling values Chapter 10 - Working with the ODBC .NET Data Provider Chapter 9

Chapter 11 - Stored ProceduresRepresents and Views whether column's value is auto increment AutoIncrement Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

AutoIncrementSeed

Starting value of auto increment, applicable when AutoIncrement is True



AutoIncrementStep Chapter 15 - Using ADO.NET inIndicates Xml Web the Services increment value Chapter 16 - ASP.NET Server Controls and Data Binding

Caption

Caption of the column


ColumnMapping the MappingType of the column Chapter 18 - Object-Relational Represents Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

ColumnName

Name of the column


DataType Chapter 21 - Messaging

Data type stored by the column

Chapter 22 - SQL Server and ADO.NET: Notes on Performance DefaultValue

Default value of the column

Appendix A - Relational Databases: Some Basic Concepts

Expression Represents the expression used to filter rows, calculate values, and so Appendix B - Commonly Used SQL Statements on Asked Questions Appendix C - ADO.NET Frequently Index MaxLenght

Represents maximum length of a text column


Represents if a column is read only

ListUnique of Listings

Indicates whether the values in a column must be unique

ReadOnly

List of Sidebars

Creating a DataColumn TheDataColumn class provides five overloaded constructors to create a DataColumn. By using these constructors you can initialize a DataColumn with its name, data type, expressions, attributes, and any combination of these. This is the format for creating a DataColumn with no arguments: public DataColumn()

For example:


ISBN:1590590732

Dim dtColumn As DataColumn = New DataColumn()

This text provides extensive coverage of ADO.NET technology ADO.NET internals, namespaces, classes, and This is the formatincluding for creating a DataColumn with the column name: interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET. Public DataColumn(String)

Table of Contents Applied ADO.NET—Building Data-Driven Solutions where String is the column name. For example: Introduction Chapter 1

- ADO.NET Basics

Chapter 3


Chapter 4


// Create Quantity Column Chapter 2 - Data Components in Visual Studio .NET DataColumn qtCol = new DataColumn("Quantity");

Chapter This is 5the-format Handling for ADO.NET creating aEvents DataColumn with the column name and its type: Chapter 6


Chapter 7 DataColumn(String, - Data Binding and Windows Forms Data-Bound Controls Public Type) Chapter 8 - Constraints and Data Relations Chapter 9

- ADO.NET Exception Handling where String is thewith column name.NET and Data TypeProvider is the column data type. Chapter 10 - Working the ODBC Chapter 11 - Stored Procedures and Views

This is the format for creating a DataColumn with the column name, its type, and its expression:


Public DataColumn(String, Type, String)

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 -String ASP.NET is Server Controls and Data Binding where first the column name, Type is the data type, and the second String is an expression. Chapter 17 - Building Real-World Web Applications

For example: Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter Dim myDataType 20 - COM Interoperability As System.Type and ADO.NET

myDataType = System.Type.GetType("System.String") Chapter 21 - Messaging Dim dtColumn As DataColumn NewonDataColumn("Name",myDataType) Chapter 22 - SQL Server and ADO.NET: = Notes Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

This is the format for creating a DataColumn with the column name, expression, and MappingType:


public DataColumn(String, Type, String, MappingType);


List of Listings where String is the column name, Type is the data type, the second String is an expression, and List of Sidebars is an attribute. MappingType

In the following example, strExpr is an expression, which is the result of the Price and the Quantity column multiplication: // Creating an expression string strExpr = "Price * Quantity"; // Create Total Column, which is result of Price*Quantity DataColumn totCol = new DataColumn("Total", myDataType, strExpr, MappingType.Attribute);


Note As you can see from the previous code, the expression strExpr is a multiplication of the Price ISBN:1590590732 by Mahesh Chand and David Talbot andQuantity columns. The Price and Quantity columns must exist in the table before you Apress © 2003 (928 pages) use them in an expression. Otherwise, the compiler will throw an exception of "column not This text provides extensive coverage of ADO.NET technology found."including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

Listing 3-1 summarizes all theand constructors. youtocan see, dcConstructorsTest creates the Price, namespaces classes, andAs how integrate both with Quantity, and Total columns of a DataTable, which later is added to a DataSet. The DataSet ADO.NET. binds to a DataGrid using the SetDataBinding method. Table of Contents Listing 3-1: Creating Columns Using Different DataColumn Constructors Applied ADO.NET—Building Data-Driven Solutions Introduction

Private Sub dcConstructorsTest() - ADO.NET Basics ' Create Customers table ChapterDim 2 -custTable Data Components in Visual Studio As DataTable = .NET New DataTable("Customers") ChapterDim 3 -dtSet ADO.NET Asin Disconnected DataSet = Environments New DataSet() Chapter'4 Create - ADO.NET in Connected Price ColumnEnvironments ChapterDim 5 -myDataType Handling ADO.NET As Events System.Type ChaptermyDataType 6 - Integrating with ADO.NET = XML System.Type.GetType("System.Int32") ChapterDim 7 -priceCol Data BindingAs andDataColumn Windows Forms= Data-Bound New DataColumn("Price", Controls myDataType) priceCol.Caption = "Price" Chapter 8 - Constraints and Data Relations ChaptercustTable.Columns.Add(priceCol) 9 - ADO.NET Exception Handling Create Quantity Column Chapter'10 - Working with the ODBC .NET Data Provider Dim qtCol As DataColumn Chapter 11 - Stored Procedures and Views= New DataColumn() = "Quantity" ChapterqtCol.ColumnName 12 - Oracle, SQLXML, and Other .NET Data Providers qtCol.DataType = System.Type.GetType("System.Int32") Chapter 13 - Developing a Custom Data Provider qtCol.Caption = "Quantity" Chapter 14 - Developing Database Web Applications using ASP.NET custTable.Columns.Add(qtCol) Chapter 15 - Using ADO.NET in Xml Web Services ' Creating an expression Chapter 16 - ASP.NET Server Controls and Data Binding Dim strExpr As String = "Price * Quantity" Chapter 17 - Building Real-World Web Applications ' Create Total Column, which is result of Price*Quantity ChapterDim 18 -totCol Object-Relational Mapping in .NET As DataColumn = New DataColumn("Total", myDataType, strExpr, _ Chapter 19 - Mapped Objects: Performance Considerations and Data Binding MappingType.Attribute) ChaptertotCol.Caption 20 - COM Interoperability and ADO.NET = "Total" Chapter'21 - Messaging Add Name column to the table. ChaptercustTable.Columns.Add(totCol) 22 - SQL Server and ADO.NET: Notes on Performance Appendix ' AAdd - Relational custTable Databases: to DataSet Some Basic Concepts dtSet.Tables.Add(custTable) Appendix B - Commonly Used SQL Statements ' C Bind dataset to the data grid Appendix - ADO.NET Frequently Asked Questions DataGrid1.SetDataBinding(dtSet, "Customers") Index End Sub List of Figures Chapter 1


To test this source code, you need to create a Windows application with a form and a DataGrid control on it. After that you can call dcConstructorsTest from either Form_Load or the button click event handler: Private Sub Form1_Load(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles MyBase.Load dcConstructorsTest() End Sub

Setting DataColumn Properties

TheDataColumn class provides properties to set a column type, name, constraints, caption, and so on. ADO.NET: Building Data-Driven Solutions You already saw Applied a list of DataColumn properties in Table 3-3. You'll now learn how to use these ISBN:1590590732 by Mahesh Chand and David Talbot properties to get and set their values. Apress © 2003 (928 pages)

Listing 3-2 creates a column with aextensive name IDcoverage and sets of itsADO.NET DataType, ReadOnly,AllowDBNull,Unique, This text provides technology including ADO.NET internals,and namespaces, classes, and properties. AutoIncrement, AutoIncremetnSeed, AutoIncrementStep interfaces, and takes a comprehensive look at XML namespaces and classes, and how toIts integrate both with Listing 3-2: Creating a DataColumn and Setting Properties ADO.NET.

Dim IdCol As DataColumn = New DataColumn() Table of Contents IdCol.ColumnName = "ID" Applied ADO.NET—Building Data-Driven Solutions IdCol.DataType = Type.GetType("System.Int32") Introduction IdCol.ReadOnly = True Chapter 1 - ADO.NET Basics IdCol.AllowDBNull = False Chapter IdCol.Unique 2 - Data Components = True in Visual Studio .NET

IdCol.AutoIncrement = True Environments Chapter 3 - ADO.NET in Disconnected IdCol.AutoIncrementSeed 1 Chapter 4 - ADO.NET in Connected=Environments IdCol.AutoIncrementStep = 1 Chapter 5 - Handling ADO.NET Events Chapter 6


Chapter 7


Chapter 8


As you can see from Listing 3-2, this code sets the AutoIncrement property as True along with the - ADO.NET Exception Handling AutoIncrementSeed and AutoIncrementStep properties. The AutoIncrement property sets a Chapter 10 - Working with the ODBC .NET Data Provider column value as an auto number. When you add a new row to the table, the value of this column is Chapter 11 automatically - Stored Procedures and Views assigned depending on the values of AutoIncrementStep and AutoIncrementSeed. Chapter 12 Oracle, SQLXML, and Other Data Providers The first value of the column starts with.NET AutoIncrementSeed, and the next value will be the previous Chapter - Developing Custom Data Provider column13 value added toathe AutoIncrementStep. In this code, the ID number value starts with 1 and Chapter 14 -byDeveloping Database Webto Applications increases 1 if you add a new row the table. Ifusing you ASP.NET set the AutoIncrementStep value to 10, the Chapter - Using ADO.NETcolumn in Xml Web Services by 10. value of15the auto number will increase Chapter 9


Having17 a primary key in a tableWeb is a common practice to maintaining the data's integrity. A primary key in a Chapter - Building Real-World Applications

table is a unique key that identifies a DataRow. For example, in the Customers table, each customer should have a unique ID. So, it's always a good idea to apply a primary key constraint on the ID table. The Chapter 19 - Mapped Objects: Performance Considerations and Data Binding propertiesAllowDBNull as False and Unique as True set a key value as the primary key, and you Chapter 20 - COM Interoperability and ADO.NET use the PrimaryKey property of a DataTable to assign a DataTable's primary key. Listing 3-2 shows Chapter 21 - Messaging theAllowDBNull as False and the Unique property as True. Now you'll set DataTable's Chapter 22 - SQL Server and ADO.NET: Notes on Performance PrimaryKey property as the ID column (see Listing 3-3). Chapter 18 - Object-Relational Mapping in .NET


Appendix B - Commonly SQL Statements Listing 3-3: Setting a Used DataColumn as the Primary Key Appendix C - ADO.NET Frequently Asked Questions Index

' Make the ID column the primary key column.

List of Figures Dim PrimaryKeyColumns() As DataColumn = New DataColumn(1) {} List of Tables PrimaryKeyColumns(0) = custTable.Columns("ID") List of Listings custTable.PrimaryKey = PrimaryKeyColumns List of Sidebars

Adding a DataColumn to a DataTable You add a DataColumn to a DataTable using the DataTable.Column.Add method. The Add method takes one argument of the DataColumn type. Listing 3-4 creates two data columns, Id and Name, and adds them to the DataTable custTable. Listing 3-4: Creating the Id and Name Data Columns of the Customers Table Dim custTable As DataTable = New DataTable("Customers")

Dim IdCol As DataColumn = New DataColumn() Applied ADO.NET: Building Data-Driven Solutions custTable.Columns.Add(IdCol) ISBN:1590590732 by Mahesh Chand and Talbot Dim nameCol As DataColumn = David New DataColumn() Apress © 2003 (928 pages) custTable.Columns.Add(nameCol) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Now you'll put allADO.NET. the pieces together (see Listing 3-5). In Listing 3-5, you create a Customers table with

the columns ID, Name, Address, DOB (date of birth), and VAR where ID is a primary key. Name and Address are string types. DOB is a date type field, and VAR is a Boolean type field. Table of Contents

ListingADO.NET—Building 3-5: Creating a Table UsingSolutions DataTable and DataColumn Applied Data-Driven Introduction Chapter 1 -Sub ADO.NET Basics Private CreateCustTable() Chapter'2 Create - Data Components in Visual Studio .NET a new DataTable ChapterDim 3 -custTable ADO.NET in Disconnected Environments As DataTable = New DataTable("Customers") Chapter'4 Create - ADO.NET ID inColumn Connected Environments

DataColumn ChapterDim 5 -IdCol HandlingAs ADO.NET Events = New DataColumn() = "ID" ChapterIdCol.ColumnName 6 - Integrating XML with ADO.NET = Windows Type.GetType("System.Int32") ChapterIdCol.DataType 7 - Data Binding and Forms Data-Bound Controls True ChapterIdCol.ReadOnly 8 - Constraints and=Data Relations False ChapterIdCol.AllowDBNull 9 - ADO.NET Exception =Handling IdCol.Unique = True IdCol.AutoIncrement = True Chapter 11 - Stored Procedures and Views IdCol.AutoIncrementSeed = 1 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers IdCol.AutoIncrementStep = 1 Chapter 13 - Developing a Custom Data Provider custTable.Columns.Add(IdCol) Chapter 14 - Developing Database Web Applications using ASP.NET ' Create Name Column ChapterDim 15 -nameCol Using ADO.NET in Xml Web Services As DataColumn = New DataColumn() ChapternameCol.ColumnName 16 - ASP.NET Server Controls and Data Binding = "Name" ChapternameCol.DataType 17 - Building Real-World Applications = Web Type.GetType("System.String") ChaptercustTable.Columns.Add(nameCol) 18 - Object-Relational Mapping in .NET Chapter'19 - Mapped Objects: Performance Considerations and Data Binding Create Address Column ChapterDim 20 -addCol COM Interoperability As DataColumn and ADO.NET = New DataColumn() = "Address" ChapteraddCol.ColumnName 21 - Messaging = Type.GetType("System.String") ChapteraddCol.DataType 22 - SQL Server and ADO.NET: Notes on Performance custTable.Columns.Add(addCol) Appendix A - Relational Databases: Some Basic Concepts ' BCreate DOB Used Column Appendix - Commonly SQL Statements Dim dobCol As DataColumn = New DataColumn() Appendix C - ADO.NET Frequently Asked Questions dobCol.ColumnName = "DOB" Index dobCol.DataType = Type.GetType("System.DateTime") List of Figures custTable.Columns.Add(dobCol) List of Tables ' VAR Column List of Listings Dim fullTimeCol As DataColumn = New DataColumn() List of Sidebars fullTimeCol.ColumnName = "VAR" fullTimeCol.DataType = Type.GetType("System.Boolean") custTable.Columns.Add(fullTimeCol) ' Make the ID column the primary key column. Dim PrimaryKeyColumns() As DataColumn = New DataColumn(1) {} PrimaryKeyColumns(0) = custTable.Columns("ID") custTable.PrimaryKey = PrimaryKeyColumns ' Create a dataset Dim ds As DataSet = New DataSet("Customers") ' Add Customers table to the dataset ds.Tables.Add(custTable) ' Attach the dataset to a DataGrid Chapter 10 - Working with the ODBC .NET Data Provider

dataGrid1.DataSource = ds.DefaultViewManager Applied ADO.NET: Building Data-Driven Solutions End Sub by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

This text provides extensive coverage of ADO.NET technology ADO.NET internals, namespaces, classes, and a DataGrid control to the form. Note To test including this program, create a Windows application and add

interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with The output of Listing 3-5 looks like Figure 3-7, which shows a table with empty columns in a DataGrid ADO.NET.

controlempty columns in a DataGrid control. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Figure 3-7: The DataGrid view of an empty DataTable


Chapter More 12 DataColumn - Oracle, SQLXML, Properties and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

You just saw some common properties of the DataColumn class, and you learned how to create and add aDataColumn to a DataTable. But guess what? DataColumn isn't finished yet. It has more to offer. Chapter 15 - Using ADO.NET in Xml Web Services Now let's see the remaining properties of DataColumn. Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 16 - ASP.NET Server Controls and Data Binding

Chapter 17 - Building Real-World Applications represents how a DataColumn is mapped in a DataSet TheColumnMapping property Web of DataColumn Chapter 18the - Object-Relational Mapping in .NET and how value of the column will be written when a DataSet is saved in XML format using the Chapter 19 - method Mapped Objects: Performance Considerations and Data Binding WriteXml of DataSet. The ColumnMapping takes a value of MappingType enumeration. Chapter TheMappingType 20 - COM Interoperability enumerationand hasADO.NET four values: Attribute,Element,Hidden, and

SimpleContent, which are mapped to an XML attribute, element, internal structure, and XmlText Chapter 21 - Messaging (respectively). Listing 3-6and shows you how to use the ColumnMapping property. Chapter 22 - SQL Server ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Listing 3-6: Using the ColumnMapping Property of DataColumn



Dim custTable As DataTable = New DataTable("Customers") Index Dim nameCol As DataColumn = New DataColumn("Name", _ List of Figures Type.GetType("System.Int32"), MappingType.Attribute) List of Tables nameCol.DataType = Type.GetType("System.String") List of Listings nameCol.ColumnMapping = MappingType.Element custTable.Columns.Add(nameCol) DataGrid1.DataSource = custTable

List of Sidebars

So far you saw how to create a new table column, set its various properties, and add it to a table. But what if you wanted to store some custom information about a column, such as a description? Guess what? You can do it. The Extended-Properties property of DataColumn lets you read and write custom properties about a DataColumn. The ExtendedProperties property takes a value of type PropertyCollection, which is inherited from the HashTable class. A hash table is a table that stores data in a key/value pair. The PropertyCollection class defines methods to add, clear, and remover properties to a collection. Some of the PropertyCollection class properties are Count,

IsFixedSize,IsReadOnly,IsSynchronized,Item,Keys, and Values.Listing 3-7 creates a ADO.NET: Building column and addsApplied four custom properties to it. Data-Driven After that, theSolutions code removes the Description property ISBN:1590590732 by Mahesh Chand and David Talbot and displays the rest of the properties using the ExtendedProperties property of DataColumn. Apress © 2003 (928 pages)

Listing 3-7: Adding This and text Removing provides extensive Custom coverage Properties of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Dim custTablenamespaces As DataTable = New DataTable("Customers") and classes, and how to integrate both with ADO.NET. Dim nameCol As DataColumn = New DataColumn("Name", _

Type.GetType("System.Int32"), MappingType.Attribute) ' Add custom properties Table of Contents nameCol.DataType = Type.GetType("System.String") Applied ADO.NET—Building Data-Driven Solutions nameCol.ExtendedProperties.Add("Description", "The Name Column") Introduction nameCol.ExtendedProperties.Add("Author", "Mahesh Chand") Chapter 1 - ADO.NET Basics nameCol.ExtendedProperties.Add("UserId", "MCB") Chapter 2 - Data Components in Visual Studio .NET nameCol.ExtendedProperties.Add("PWD", "Password") Chapter 3 - ADO.NET in Disconnected Environments custTable.Columns.Add(nameCol) Chapter 4 - ADO.NET Connected Environments ' Remove Author inproperty Chapter 5 - Handling ADO.NET Events nameCol.ExtendedProperties.Remove("Author") Chapter ' Read 6 custom - Integrating properties XML with ADO.NET Dim str String Chapter 7 -As Data Binding and Windows Forms Data-Bound Controls Dim i8 As- Constraints Integer and Data Relations Chapter str = nameCol.ExtendedProperties("Description").ToString() Chapter 9 - ADO.NET Exception Handling str =10str + ", with " +the nameCol.ExtendedProperties("UserId").ToString() Chapter - Working ODBC .NET Data Provider str = str + ", " + nameCol.ExtendedProperties("PWD").ToString() Chapter 11 - Stored Procedures and Views MessageBox.Show(str) Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in only) Xml Web Services TheOrdinal property (read of DataColumn returns the position of a column in a Chapter 16 ASP.NET Server Controls and Data Binding DataColumnCollection, and the MaxLength (get and set both types) property represents the Chapter 17 -length Building Web Applications maximum of Real-World a column. Listing 3-8 shows how to use the Ordinal and MaxLength properties. Chapter 18 - Object-Relational Mapping in .NET

Listing19 3-8: Using the Ordinal and MaxLength Properties Chapter - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Dim custTable As DataTable = New DataTable("Customers") Chapter 22 - SQL Server and ADO.NET:= Notes Performance Dim nameCol As DataColumn New on DataColumn("Name", _ Appendix A - Relational Databases: Some Basic Concepts Type.GetType("System.Int32"), MappingType.Attribute) Appendix custTable.Columns.Add(nameCol) B - Commonly Used SQL Statements

nameCol New DataColumn() Appendix C -=ADO.NET Frequently Asked Questions nameCol.DataType = Type.GetType("System.String") Index nameCol.Caption = "New Column" List of Figures nameCol.ColumnName = "Col2" List of Tables nameCol.MaxLength = 240 List of Listings custTable.Columns.Add(nameCol) Dim str As String str = "Ordinal " + nameCol.Ordinal.ToString() str = str + " ,Length " + nameCol.MaxLength.ToString() MessageBox.Show(str)

List of Sidebars

The DataRow ADataRow represents a row of data in a DataTable. You add data to the DataTable using the DataRow object. A DataRowCollection object represents a collection of DataRows of a DataTable.

You use the DataTable'sNewRow method to return a DataRow object, add values to the DataRow, and ADO.NET: Solutions Add method. add the row to theApplied DataTable againBuilding by usingData-Driven DataRowCollection's by Mahesh Chand and David Talbot

ISBN:1590590732

Table 3-4 describes Apress DataRow © 2003 (928 class pages) properties, and Table 3-5 describes the methods. This text provides extensive coverage of ADO.NET technology including Class ADO.NET internals, namespaces, classes, and Table 3-4: The DataRow Properties

PROPERTY

interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with DESCRIPTION ADO.NET.

Item

Represents an item of a row

ItemArray Table of Contents Represents all values in a row Applied ADO.NET—Building Data-Driven Solutions

RowState

Introduction

Indicates the current state of a row

Table Chapter 1

Returns - ADO.NET Basicsthe DataTable to which this row is attached

Chapter 2


Chapter 3


Table 3-5: DataRow Class Methods Chapter 4 - The ADO.NET in Connected Environments Chapter 5 - Handling ADO.NET Events METHOD DESCRIPTION Chapter 6


AcceptChanges all theForms changes made toControls this row Chapter 7 - Data BindingCommits and Windows Data-Bound Chapter 8 - Constraints and Data Relations BeginEdit Chapter 9

Starts an edit operation on a row


CancelEdit Cancels the.NET current edit on a row Chapter 10 - Working with the ODBC Data Provider Chapter 11 - Stored Procedures Views Delete Deletesand a DataRow Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

EndEdit Ends the current edit on a row Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web rows Applications using ASP.NET GetChildRows Returns child of a DataRow Chapter 15 - Using ADO.NET in Xml Web Services

GetParentRows

Returns parent rows of a DataRow.


Chapter 17 - Building Real-World Applications RejectChanges Rejects Web all the changes made since last AcceptChanges Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

You access DataRow membersand through the DataTable columns. A column acts as an item of the row. Chapter 20 - COM Interoperability ADO.NET For example, if a DataTable has three columns such as Id, Name, and Address, then a row will have Chapter 21 - Messaging

three members: Id, Name, and Address. You access DataTable members using the column names. For example,Listing 3-9 sets values of the Id, Name, and Address columns. Appendix A - Relational Databases: Some Basic Concepts Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Appendix B - Commonly Used SQL Statements Listing 3-9: Setting the Values of the Id, Address, and Name Columns of a DataRow Appendix C - ADO.NET Frequently Asked Questions Index

Dim row1 As DataRow = custTable.NewRow() row1("id") = 1001 List of Tables row1("Address") = "43 Lanewood Road, Cito, CA" List of Listings row1("Name") = "George Bishop " List of Figures

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After setting a row member's values, you add the row to the row collection with the DataTable.Rows.Add method. The following code adds a row to the collection: custTable.Rows.Add(row1)

TheRejectChanges method of the DataRow rejects recent changes on that row. For example, if you have recently added row1 to the DataTable, then calling the RejectChanges method as follows:

row1.RejectChanges() Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

won't add the rowApress to the©DataTable. 2003 (928 pages) This text provides extensive coverage of ADO.NET technology

You can also delete a rowADO.NET from a DataTable by calling the DataRow's including internals, namespaces, classes, and Delete method: interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Row1.Delete()ADO.NET.

Table of Contents

Caution TheRejectChanges Delete methods may not work together if you're applying both Applied ADO.NET—Building Data-Drivenand Solutions Introduction Chapter 1

methods on the same row because RejectChanges doesn't add a row to the DataTable.

- ADO.NET Basics

Listing 3-10 shows a program that creates a DataTable with three columns (Id, Name, and Address) and - Data Components in Visual Studio .NET adds three rows to the DataTable. At the end, this program attaches the newly created DataTable to a Chapter 3 - ADO.NET in Disconnected Environments DataGrid control using a DataSet. Chapter 2 Chapter 4


Chapter - Handling Listing53-10: AddingADO.NET Rows toEvents a DataTable Using DataRow Chapter 6 - Integrating XML with ADO.NET Chapter 7

- Data Binding and Windows Forms Data-Bound Controls ' This method creates Customers table Chapter 8 - Constraints and Data Relations Private Sub CreateCustomersTable() Chapter'9 Create - ADO.NET Exception Handling a new DataTable. ChapterDim 10 -custTable Working with As the ODBC .NET Data Provider System.Data.DataTable = New DataTable("Customers") ChapterDim 11 -dtColumn Stored Procedures and Views As DataColumn Chapter'12 - Oracle,id SQLXML, and Other .NET Data Providers Create Column. ChapterdtColumn 13 - Developing = New a Custom DataColumn() Data Provider = Web System.Type.GetType("System.Int32") ChapterdtColumn.DataType 14 - Developing Database Applications using ASP.NET "id" ChapterdtColumn.ColumnName 15 - Using ADO.NET in Xml = Web Services = "Cust ChapterdtColumn.Caption 16 - ASP.NET Server Controls and ID" Data Binding True ChapterdtColumn.ReadOnly 17 - Building Real-World=Web Applications True in .NET ChapterdtColumn.Unique 18 - Object-Relational=Mapping ' Add id Column to the DataColumnCollection. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding custTable.Columns.Add(dtColumn) Chapter 20 - COM Interoperability and ADO.NET ' Create Name column. Chapter 21 - Messaging dtColumn = New DataColumn() Chapter 22 - SQL Server and ADO.NET: Notes on Performance dtColumn.DataType = System.Type.GetType("System.String") Appendix A - Relational Databases: Some Basic Concepts dtColumn.ColumnName = "Name" Appendix B - Commonly Used SQL Statements dtColumn.Caption = "Cust Name" Appendix C ADO.NET Frequently Asked dtColumn.AutoIncrement =Questions False Index dtColumn.ReadOnly = False List of Figures dtColumn.Unique = False List of Tables ' Add Name column to the table. List of Listings custTable.Columns.Add(dtColumn) ' Create Address column. List of Sidebars dtColumn = New DataColumn() dtColumn.DataType = System.Type.GetType("System.String") dtColumn.ColumnName = "Address" dtColumn.Caption = "Address" dtColumn.ReadOnly = False dtColumn.Unique = False ' Add Address column to the table. custTable.Columns.Add(dtColumn) ' Make the ID column the primary key column. Dim PrimaryKeyColumns() As DataColumn = New DataColumn(1) {} PrimaryKeyColumns(0) = custTable.Columns("id")

custTable.PrimaryKey = PrimaryKeyColumns Appliedthe ADO.NET: Building Data-Driven Solutions ' Instantiate DataSet variable. ISBN:1590590732 by Mahesh Chand and David Talbot Dim ds As DataSet = New DataSet("Customers") Apress © 2003 (928 pages) ' Add the custTable to the DataSet. This text provides extensive coverage of ADO.NET technology ds.Tables.Add(custTable) including ADO.NET internals,using namespaces, ' Add rows to the custTable its classes, NewRowand method interfaces, and takes a comprehensive look at XML ' I add three customers with thier addresses, name and id namespaces and classes, and how to integrate both with Dim row1 ADO.NET. As DataRow = custTable.NewRow() row1("id") = 1001 row1("Address") = "43 Lanewood Road, Cito, CA" Table of Contents row1("Name") = "George Bishop " AppliedcustTable.Rows.Add(row1) ADO.NET—Building Data-Driven Solutions Introduction Dim row2 As DataRow = custTable.NewRow() Chapterrow2("id") 1 - ADO.NET = Basics 1002 Chapterrow2("Name") 2 - Data Components = "Rock in Visual JoeStudio " .NET = "KingEnvironments of Prusssia, PA" Chapterrow2("Address") 3 - ADO.NET in Disconnected ChaptercustTable.Rows.Add(row2) 4 - ADO.NET in Connected Environments AsADO.NET DataRow = custTable.NewRow() ChapterDim 5 -row3 Handling Events = XML 1003 Chapterrow3("id") 6 - Integrating with ADO.NET "Miranda " Chapterrow3("Name") 7 - Data Binding=and Windows Forms Data-Bound Controls row3("Address") = "279 P. Avenue, Bridgetown, PA" Chapter 8 - Constraints and Data Relations custTable.Rows.Add(row3) Chapter 9 - ADO.NET Exception Handling 'row3.RejectChanges() Chapter 10 - Working with the ODBC .NET Data Provider 'row2.Delete() Chapter 11 - Stored Procedures and Views ' Bind dataset to the data grid Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers dataGrid1.DataSource = ds.DefaultViewManager Chapter 13 - Developing a Custom Data Provider End Sub Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter Caution 17 - Building As youReal-World can see from WebListing Applications 3-10, the Id column of the Customers table is read only (the

ReadOnly property is True). Chapter 18 - Object-Relational Mapping in .NETThat means you won't be able to add data to the table. If you want toObjects: add data from the front end, you need setBinding the ReadOnly property to False. Chapter 19 - Mapped Performance Considerations and to Data Chapter 20 - COM Interoperability and ADO.NET

The output of the program looks like Figure 3-8.



Figure 3-8: ADataTable with three rows Note To run this program, create a Windows application and drop a DataGrid control on the form. After that you can either call CreateCustomersTable in Listing 3-3 from the form's Load event or from a button click handler.You can write a Load event by double-clicking on the form or by opening the Properties window. If you uncomment row3.RejectChanges() and row2.Delete() at the end of Listing 3-10, the

RejectChanges method rejects the addition of row 3, and the Delete method deletes row 2. Applied ADO.NET: Building Data-Driven Solutions

ISBN:1590590732 by Mahesh Chand RejectChanges and David Talbot and Delete Listing 3-11: Calling DataRow's Methods

Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology row3.RejectChanges() including ADO.NET internals, namespaces, classes, and row2.Delete()interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

TheDataRowState enumeration returns the current state of a row. It's useful during operations when you want to know the current state of a row. Table 3-6 lists the values of the DataRowState Applied ADO.NET—Building Data-Driven Solutions enumeration.

Table of Contents Introduction

Chapter 1 - The ADO.NET Basics Table 3-6: DataRowState Enumeration Members Chapter 2 - Data Components in Visual Studio .NET

MEMBER DESCRIPTION Chapter 3 - ADO.NET in Disconnected Environments Chapter 4 Added Chapter 5

- ADO.NET Connected Environments Rowinhas been added, and AcceptChanges has not been called. - Handling ADO.NET Events

Deleted Row was using the Delete method. Chapter 6 - Integrating XML deleted with ADO.NET Chapter 7 - Data Binding andcreated Windows Data-Bound Controls Detached Row was butForms deleted before it was added to the collection. Chapter 8 - Constraints and Data Relations

Modified RowException has beenHandling modified, but AcceptChanges has not been called yet. Chapter 9 - ADO.NET Chapter 10 - Working with the ODBC .NET Data Unchanged Row has not changed sinceProvider the last AcceptChanges was called. Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

TheRowState propertya of a DataRow returns the DataRowState enumeration. You can use this to find Chapter 13 - Developing Custom Data Provider out the14 current state of Database a row. ForWeb example, Listing 3-12ASP.NET calls RowState just after the Delete and Chapter - Developing Applications using RejectChanges methods.in Xml Web Services Chapter 15 - Using ADO.NET Chapter 16 - ASP.NET Server Controls and Data Binding

Listing 3-12: Calling the RowState Property

Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

row3.RejectChanges() Chapter 19 - Mapped Objects: Performance Considerations and Data Binding MessageBox.Show(row2.RowState.ToString()) row2.Delete() Chapter 21 - Messaging MessageBox.Show(row3.RowState.ToString()) Chapter 20 - COM Interoperability and ADO.NET

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

The DataRelation

Index

List of Figures

To provide data integrity and consistency, you should use relationships between two tables. You achieve this relationship by defining a primary key in one table and using a foreign key in the other table. Say a List of Listings customer has multiple orders; the Customers table stores the customer details, and the Orders table List of Sidebars stores all the order details. To avoid the redundancy of data, you define the primary key of the Customers table as a foreign key in the Orders table. List of Tables

Note In general this relationship is called the parent/child,ormaster/details, relationship. In this example, the Customers table is also the parent table, and the Orders table is also the child table. TheParentRelations property of DataTable represents the parent relationship, and ChildRelations represents the child relationship. Caution The data type of both columns, which you're linking through a relationship in the Customers and the Orders tables, must be identical. You can also access this relationship though a DataSet using its Relations property. To create a

relationship between two columns, you create two DataColumn objects and pass them as ADO.NET: Building Data-Driven Solutions DataRelation Applied arguments. by Mahesh Chand and David Talbot

ISBN:1590590732

Apress © 2003 pages) Listing 3-13 shows you how to(928 create a customer/order relationship between the Customers and Orders table through theThis Customers table's id column, referenced as CustId in the Orders table. The text provides extensive coverage of ADO.NET technology ADO.NET internals, namespaces, classes, and relationship, the first DataColumn, DataRelation including constructor takes three arguments: the name of the interfaces, andAfter takesthat a comprehensive look at XML and the second DataColumn. you call DataTable's ParentRelation.Add method with namespaces and classes, and how to integrate both with DataRelation ADO.NET. as an argument. (Listing 3-15 shows the full source code of this example.) In this code, dtSet is a DataSet object, which we discuss in the following section.

Listing 3-13: Creating a Customer/Order Relationship Using DataRelation Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Private Sub BindData() ChapterDim 1 -dtRelation ADO.NET BasicsAs DataRelation ChapterDim 2 -CustCol Data Components As DataColumn in Visual Studio = dtSet.Tables("Customers").Columns("id") .NET

DataColumn = dtSet.Tables("Orders").Columns("CustId") ChapterDim 3 -orderCol ADO.NET in As Disconnected Environments DataRelation("CustOrderRelation", CustCol, orderCol) ChapterdtRelation 4 - ADO.NET = in New Connected Environments ChapterdtSet.Tables("Orders").ParentRelations.Add(dtRelation) 5 - Handling ADO.NET Events ChapterdataGrid1.SetDataBinding(dtSet,"Customers") 6 - Integrating XML with ADO.NET

End Sub Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Chapter 8


Chapter 9



The DataTable


In the previous sectionsa you've columns and rows are the building blocks of a DataTable. You Chapter 13 - Developing Customseen Datathat Provider need to work with the DataColumn and DataRow objects to create DataTables and add data to them. Besides creating a DataTable schema and adding rows to it, a DataTable has more to offer. The Chapter 15 - Using ADO.NET in Xml Web Services DataTable object represents a DataTable. Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 16 - ASP.NET Server Controls and Data Binding

Chapter 17 -take Building Real-World Web Applications First you'll a look at the DataTable class properties and methods. Table 3-7 describes some Chapter 18DataTable - Object-Relational Mapping .NET3-8 summarizes some of the common DataTable methods. common properties, andin Table Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - The COMDataTable Interoperability andProperties ADO.NET Table 3-7: Class Chapter 21 - Messaging

PROPERTIES

DESCRIPTION

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Columns Represents allBasic tableConcepts columns Appendix B - Commonly Used SQL Statements

Constraints

Represents all table constaints

Appendix C - ADO.NET Frequently Asked Questions Index DataSet List of Figures

DefaultView

List of Tables

ListChildRelation of Listings List of Sidebars

Returns the DataSet for the table Customized view of the DataTable Returns child relations for the DataTable

ParentRelation

Returns parent relations for the DataTable

PrimaryKey

Represents an array of columns that function as primary key for the table

Rows

All rows of the DataTable

TableName

Name of the table

Table 3-8: The DataTable Class Methods

METHOD

DESCRIPTION Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot Commits all the changes made since the last AcceptChanges was called Apress © 2003 (928 pages)

AcceptChanges Clear Clone Copy

Deletes all DataTable data of ADO.NET technology This text provides extensive coverage including ADO.NET internals, namespaces, classes, and Creates clone of a datatable including its schema interfaces, and a takes a comprehensive look at XML namespaces and classes, and how to integrate both with Copies a DataTable including its schema ADO.NET.

NewRow Table of Contents RejectChanges

Creates a new row, which is later added by calling the Rows.Addmethod Rejects all changes made after the last AcceptChanges was called


Reset Introduction

Resets a DataTable's original state

Chapter 1 - ADO.NET Basics Select Gets an array of rows based on the criteria Chapter 2 - Data Components in Visual Studio .NET Chapter 3

- ADO.NET in Disconnected Environments TheDataTable classinprovides methods and properties to remove, copy, and clone data tables. Not only Chapter 4 - ADO.NET Connected Environments

that, but can alsoADO.NET apply filters on a DataTable. The Constraints property provides access to all Chapter 5 you - Handling Events the constraints that a DataTable has. You can also access the child/parent relationship using Chapter 6 - Integrating XML with ADO.NET ChildRelation and ParentRelation. we'll create two tables-Customers and Orders-and set a Chapter 7 - Data Binding and Windows FormsNow Data-Bound Controls relationship between them. To test this application, you build a Windows application using Visual Basic and Chapter 8 - Constraints and Data Relations add a DataGrid control to the form. After that you call the CreateCustomersTable, - ADO.NET Exception Handling CreateOrdersTable, and BindData methods from the form constructor after Chapter 10 - Working with the ODBC .NET Data Provider InitializeComonent. The form constructor looks like Listing 3-14. Chapter 9


Chapter - Oracle, SQLXML, and Other .NET Data Providers Listing12 3-14: Form's Constructor Calling CreateCustomersTable, CreateOrdersTable, and Chapter 13 - Developing a Custom Data Provider BindData Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Private Sub Form1_Load(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles MyBase.Load ChapterCreateCustomersTable() 17 - Building Real-World Web Applications ChapterCreateOrdersTable() 18 - Object-Relational Mapping in .NET ChapterBindData() 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET End Sub Chapter 16 - ASP.NET Server Controls and Data Binding

Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

You alsoBneed to add aUsed DataSet variable, dtSet, in the beginning of your form: Appendix - Commonly SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Public Class Form1 Index Inherits System.Windows.Forms.Form List of Figures Private List of Tables dtSet As System.Data.DataSet List of Listings List of Sidebars

In Listing 3-15, the CreateCustomersTable method creates the Customers data table with Id, Name, and Address columns and adds three data rows to it. The CreateOrdersTable method creates the Orders table with OrderId, CustId, Name, and Description columns and adds data to it. The BindData method creates a customer/orders relationship and binds the data to a DataGrid control using DataSet. Listing 3-15: Customer/Orders Relationship Example Private Sub CreateCustomersTable() ' Create a new DataTable. Dim custTable As System.Data.DataTable = New DataTable("Customers") ' Create id, Name, and Address Columns and

' add these columns to custTable Applied ADO.NET: Building Data-Driven Solutions ' See source code for details ISBN:1590590732 by Mahesh Chand and Talbot key column. ' Make the ID column theDavid primary Apress © 2003 (928 pages) Dim PrimaryKeyColumns() As DataColumn = New DataColumn(1) {} This text provides extensive coverage of ADO.NET technology PrimaryKeyColumns(0) = custTable.Columns("id") including ADO.NET internals, namespaces, classes, and custTable.PrimaryKey = PrimaryKeyColumns interfaces, and takes a comprehensive look at XML ' Instantiate the and DataSet variable. namespaces classes, and how to integrate both with dtSet = New DataSet("Customers") ADO.NET. ' Add the custTable to the DataSet. dtSet.Tables.Add(custTable) Table of ' Contents Add rows to the custTable using its NewRow method Applied'ADO.NET—Building Data-Driven Solutions I add three customers with thier addresses, name and id Introduction ' See source code for details Chapter - ADO.NET Basics End1 Sub Chapter ' This 2 - Data method Components creates in Visual Orders Studio table .NET with Private Sub CreateOrdersTable() Chapter 3 - ADO.NET in Disconnected Environments Orders table. Chapter'4 Create - ADO.NET in Connected Environments AsEvents DataTable = New DataTable("Orders") ChapterDim 5 -ordersTable Handling ADO.NET OrderId, Name, CustId, Description columns Chapter'6 Create - Integrating XML with ADO.NET them to and ordersTable Chapter'7 Add - Data Binding Windows Forms Data-Bound Controls ' See source code for more details Chapter 8 - Constraints and Data Relations ' Add ordersTable to the dataset Chapter 9 - ADO.NET Exception Handling dtSet.Tables.Add(ordersTable) Chapter 10 - Working with the ODBC .NET Data Provider ' Add two rows to Customer Id 1001 Chapter 11 - Stored Procedures and Views dtRow = ordersTable.NewRow() Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers dtRow("OrderId") = 0 ChapterdtRow("Name") 13 - Developing a Custom Provider = "ASPData Book" ChapterdtRow("CustId") 14 - Developing Database Web Applications using ASP.NET = 1001 ChapterdtRow("Description") 15 - Using ADO.NET in Xml Web Services = "Same Day" ChapterordersTable.Rows.Add(dtRow) 16 - ASP.NET Server Controls and Data Binding ChapterdtRow 17 - Building Real-World Web Applications = ordersTable.NewRow() ChapterdtRow("OrderId") 18 - Object-Relational Mapping = 1 in .NET = "C# Book" Considerations and Data Binding ChapterdtRow("Name") 19 - Mapped Objects: Performance = 1001 ChapterdtRow("CustId") 20 - COM Interoperability and ADO.NET = "2 Day Air" ChapterdtRow("Description") 21 - Messaging ChapterordersTable.Rows.Add(dtRow) 22 - SQL Server and ADO.NET: Notes on Performance ' AAdd two rows to Customer Id 1002 Appendix - Relational Databases: Some Basic Concepts dtRow = ordersTable.NewRow() Appendix B - Commonly Used SQL Statements dtRow("OrderId") = 2 Appendix C - ADO.NET Frequently Asked Questions dtRow("Name") = "Data Quest" Index dtRow("Description") = "Monthly Magazine" List of Figures dtRow("CustId") = 1002 List of Tables ordersTable.Rows.Add(dtRow) List of Listings dtRow = ordersTable.NewRow() List of Sidebars dtRow("OrderId") = 3 dtRow("Name") = "PC Magazine" dtRow("Description") = "Monthly Magazine" dtRow("CustId") = 1002 ordersTable.Rows.Add(dtRow) ' Add two rows to Customer Id 1003 dtRow = ordersTable.NewRow() dtRow("OrderId") = 4 dtRow("Name") = "PC Magazine" dtRow("Description") = "Monthly Magazine" dtRow("CustId") = 1003 ordersTable.Rows.Add(dtRow)

dtRow = ordersTable.NewRow() Applied ADO.NET: dtRow("OrderId") = 5 Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot dtRow("Name") = "C# Book" Apress © 2003 (928 pages) dtRow("CustId") = 1003 This text provides extensive coverage dtRow("Description") = "2 Day Air" of ADO.NET technology including ADO.NET internals, namespaces, classes, and ordersTable.Rows.Add(dtRow) interfaces, and takes a comprehensive look at XML End Sub namespaces and classes, and how to integrate both with ADO.NET.

' This method creates a customer order relationship and binds data tables ' to the data grid cotnrol using dataset. TablePrivate of Contents Sub BindData() AppliedDim ADO.NET—Building Solutions dtRelation Data-Driven As DataRelation Introduction Dim CustCol As DataColumn = dtSet.Tables("Customers").Columns("id") ChapterDim 1 -orderCol ADO.NET Basics As DataColumn = dtSet.Tables("Orders").Columns("CustId") Chapter 2

- Data Components in Visual Studio .NET DataRelation("CustOrderRelation", CustCol, orderCol) ChapterdtRelation 3 - ADO.NET = in New Disconnected Environments ChapterdtSet.Tables("Orders").ParentRelations.Add(dtRelation) 4 - ADO.NET in Connected Environments

"Customers") ChapterDataGrid1.SetDataBinding(dtSet, 5 - Handling ADO.NET Events End6 Sub Chapter - Integrating XML with ADO.NET Chapter 7


Chapter 8


Chapter 9


Listing 3-15 shows all three CreateCustomerTable,CreateOrdersTable, and BindData methods.


Chapter Procedures and Views As you 11 can- Stored see from the CreateCustomersTable method in Listing 3-15, it creates the Customers Chapter table using 12 - DataTable Oracle, SQLXML, andand adds Other the Id, .NET Name Data and Providers Address columns to the table. You use DataColumn

to add these columns. The Id column has properties such as ReadOnly and Unique. As discussed Chapter 13 - Developing a Custom Data Provider earlier,14 to add a columnDatabase to a DataTable, you create DataColumn object, set its properties, and then Chapter - Developing Web Applications usingaASP.NET call the15 DataTable.Coumns.Add method. Similar to the id column, you add two more columns, Name Chapter - Using ADO.NET in Xml Web Services and Address, of string type to the table. that you make the id column the primary key by setting Chapter 16 - ASP.NET Server Controls and After Data Binding DataTable.PrimaryKey as Web the idApplications column: Chapter 17 - Building Real-World Chapter 18 - Object-Relational Mapping in .NET

PrimaryKeyColumns(0) = custTable.Columns("id") Chapter 19 - Mapped Objects: Performance Considerations and Data Binding custTable.PrimaryKey PrimaryKeyColumns Chapter 20 - COM Interoperability= and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

After creating a DataTable you add it to a DataSet using the DataSet.Tables.Addmethod. This method takes one argument of type DataTable:



dtSet = New DataSet("Customers") dtSet.Tables.Add(custTable)

Index


List of Listings Now, the last step is to add data to DataTable. You add data using DataRow. First, you create a List DataRow of Sidebars object using DataTable'sNewRow method, add data to a DataRow's items, and add DataRow

to the DataTable using the DataTable.Rows.Add method. You'll follow the same method for the second table in CreateOrdersTable to create the Orders table. The Orders table has the fields OrderId, Name, Description, and CustId. The BindData method creates a relationship by using DataRelation and binds the id column of the Customers tables to the CustId column of the Orders table. The name of the relationship is CustOrderRelation. After that you bind DataTable to the DataGrid using the SetDataBinding method. The output of Listing 3-15 looks like Figure 3-9.


ISBN:1590590732


Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Figure 3-9: A DataGrid with data relations


ADO.NET Basics If you click-the CustOrderRelation link, the output looks like Figure 3-10.

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Figure 3-10: Orders record for Customers id 1001


Chapter and Data Binding As you 16 can- ASP.NET see fromServer FigureControls 3-10,DataGrid shows all the orders for Customer id 1001. Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

More DataTable Operations


Adding and deleting are two common operations when working with databases. You've already learned

Chapter 21 -to Messaging about how add data to a DataTable using a DataRow. In this section you'll see how to add, delete, Chapter 22 SQL Server and ADO.NET: Notes on Performance sort, and search data programmatically. You'll keep all data in memory in the form of DataTables, but Appendix A -see Relational Some you'll also a SaveDatabases: option, which willBasic saveConcepts data in XML format. This is a simple Windows Forms Appendix B - Commonly Used SQL Statements application. Appendix C - ADO.NET Frequently Asked Questions

The first step is to build a GUI (see Figure 3-11). To build this GUI, you create a Windows Application Index

project. After that, add a DataGrid control, four Button controls, seven TextBox controls, five GroupBox controls, and some Label controls. Then adjust them on your form. You can also change the List of Tables background color of the controls. List of Figures

List of Listings

List of Sidebars


ISBN:1590590732



- ADO.NET Basics

Chapter 2

- Data Components in Visual Studio .NET Figure Add, sort, and search operations in a DataTable Chapter 3 - 3-11: ADO.NET indelete, Disconnected Environments Chapter 4


In this application, we show you all basic common operations such as adding, deleting, sorting, and - Handling ADO.NET Events searching rows. The Add Row button reads the name and address, adds a new row in the DataTable, Chapter 6 - Integrating XML with ADO.NET and displays the added row in the DataGrid. The Delete Rows button deletes rows based on the entered Chapter 7 - Data Binding and Windows Forms Data-Bound Controls criteria. To delete rows, you enter the column name and value, and the Delete Rows button will delete all Chapter 8 - Constraints and Data Relations the rows that meet the criteria. The Search button reads column name and values entered in the text Chapter 9 - ADO.NET Exception Handling boxes and returns data that matches the criteria. The Apply Sort button reads a column and sorts rows Chapter 10 that - Working with theSave ODBCmethod .NET Data Provider based on column. The saves the current data of the DataTable to an XML document. Chapter 5


Note don'tSQLXML, have to create the .NET sameData formProviders as shown in Figure 3-11. The only thing you need to Chapter 12 You - Oracle, and Other is a DataGrid the same number of TextBox and Button controls. Chapter 13 have - Developing a Customwith Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Now, you change the names of the form controls and add the DataSet variable dtSet and the DataTable variable custTable to the beginning of the form. Besides the variables defined for the Chapter 16 - ASP.NET Server Controls and Data Binding controls (see the MoreDataTableOpsSamp sample available with the source code for details), add two Chapter 17 - Building Real-World Web Applications variables of type DataTable and DataSet, as shown in Listing 3-16. Chapter 15 - Using ADO.NET in Xml Web Services


Chapter - Mapped Objects: Performanceand Considerations and Data Binding Listing19 3-16: Class-Level DataTable DataSet Variables Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

Private custTable As DataTable

Chapter 22 -dtSet SQL Server ADO.NET: Notes on Performance Private As and DataSet Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index Now you create the Customers table with three columns: id, Name, and Address. You've already learned

how add columns to a DataTable using a DataColumn and binding it to a DataGrid. The List of to Figures CreateCustomersTable method creates the Customers table. After creating the Customers table, you List of Tables addofthe DataTable to the DataSet using the DataSet.Tables.Add method. The List Listings CreateCustomersTable method looks like Listing 3-17. List of Sidebars Listing 3-17: The CreateCustomersTable Method ' This method creates Customers table Private Sub CreateCustomersTable() ' Create a new DataTable. custTable = New DataTable("Customers") Dim dtColumn As DataColumn ' Create id Column dtColumn = New DataColumn() dtColumn.DataType = System.Type.GetType("System.Int32")

dtColumn.ColumnName = "id" Applied ADO.NET: Building dtColumn.AutoIncrement = True Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David dtColumn.AutoIncrementSeed = Talbot 100 Apress © 2003 (928 pages) dtColumn.AutoIncrementStep = 1 This text provides extensive dtColumn.Caption = "Cust ID"coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and dtColumn.ReadOnly = True interfaces, and takes a comprehensive look at XML dtColumn.Unique True namespaces= and classes, and how to integrate both with ' Add id ADO.NET. Column to the DataColumnCollection. custTable.Columns.Add(dtColumn) ' Create Name column. Table ofdtColumn Contents = New DataColumn() ApplieddtColumn.DataType ADO.NET—Building Data-Driven Solutions = System.Type.GetType("System.String") Introduction dtColumn.ColumnName = "Name" ChapterdtColumn.Caption 1 - ADO.NET Basics = "Cust Name" ChapterdtColumn.AutoIncrement 2 - Data Components in Visual=Studio False .NET = False ChapterdtColumn.ReadOnly 3 - ADO.NET in Disconnected Environments = False ChapterdtColumn.Unique 4 - ADO.NET in Connected Environments Name column to the table. Chapter'5 Add - Handling ADO.NET Events ChaptercustTable.Columns.Add(dtColumn) 6 - Integrating XML with ADO.NET Address column.Forms Data-Bound Controls Chapter'7 Create - Data Binding and Windows dtColumn = New DataColumn() Chapter 8 - Constraints and Data Relations dtColumn.DataType = System.Type.GetType("System.String") Chapter 9 - ADO.NET Exception Handling dtColumn.ColumnName = "Address" Chapter 10 - Working with the ODBC .NET Data Provider dtColumn.Caption = "Address" Chapter 11 - Stored Procedures and Views dtColumn.ReadOnly = False Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers dtColumn.Unique = False Chapter'13 - Developing Add Addressa Custom columnData to Provider the table. ChaptercustTable.Columns.Add(dtColumn) 14 - Developing Database Web Applications using ASP.NET Chapter'15 - Using ADO.NET in Xml Web Make the ID column theServices primary key column. ChapterDim 16 -PrimaryKeyColumns() ASP.NET Server Controls andAs Data Binding DataColumn = New DataColumn(1) {} ChapterPrimaryKeyColumns(0) 17 - Building Real-World Web=Applications custTable.Columns("id") ChaptercustTable.PrimaryKey 18 - Object-Relational Mapping = in PrimaryKeyColumns .NET Instantiate thePerformance DataSet Considerations variable. and Data Binding Chapter'19 - Mapped Objects: = New DataSet("Customers") ChapterdtSet 20 - COM Interoperability and ADO.NET Add the custTable to the DataSet. Chapter'21 - Messaging ChapterdtSet.Tables.Add(custTable) 22 - SQL Server and ADO.NET: Notes on Performance RefreshData() Appendix A - Relational Databases: Some Basic Concepts End Sub Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List At of theFigures end of the CreateCustomersTable method you call the RefreshData method, which refreshes List of Tables theDataGrid contents and fills them with the current data of the DataTable by setting DataGrid's List of Listings property to the DataSet'sDefaultViewManager. The RefreshData method looks like DataSource List Sidebars theoffollowing:

Private Sub RefreshData() dataGrid1.DataSource = dtSet.DefaultViewManager End Sub

As you can see from Figure 3-12, the Add Row button adds a new row to the Customers' DataTable with the Name and Address columns reading from the Name and Address text boxes. The Delete Rows button deletes the row number inserted in the Enter Row # text box. The Search button searches and returns rows that contain the name entered in the Enter Name text box of the Search group box.


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3 - 3-12: ADO.NET in Disconnected Figure Adding rows to the Environments DataTable Chapter 4


Chapter 5 it's - Handling ADO.NET OK, now time to write codeEvents for the button event handlers. You can write button event handlers by Chapter double-clicking 6 - Integrating the buttons XML or with using ADO.NET the Properties windows. First, you write the event handler for the Add

Row button with the handler AddRow_Click. After that, write event handlers for the Delete Rows Chapter 7 - Data Binding and name Windows Forms Data-Bound Controls and Search buttons; theand event handler names for these buttons are DeleteRow_Click and Chapter 8 - Constraints Data Relations SearchButton_Click, respectively. Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

You add a new row to the DataTable using DataRow and call the Add and AcceptChanges methods of the DataTable.Listing 3-18 shows the Add Row button click event handler.


Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter - Developing a Custom Data Provider Listing13 3-18: The AddRowBtn_Click Method


Private Sub AddRowBtn_Click(ByVal sender As System.Object, _

Chapter 16 -eASP.NET Server Controls and Data Binding AddRowBtn.Click ByVal As System.EventArgs) Handles Chapter'17 Building Real-World Web Applications Add rows to the custTable using its NewRow method Chapter'18 Object-Relational Mapping inwith .NET thier addresses, name and id I -add three customers ChapterDim 19 -myDataRow Mapped Objects: and Data Binding As Performance DataRow =Considerations custTable.NewRow() ChaptermyDataRow("Name") 20 - COM Interoperability= and ADO.NET TextBox4.Text.ToString() ChaptermyDataRow("Address") 21 - Messaging = TextBox5.Text.ToString() ChaptercustTable.Rows.Add(myDataRow) 22 - SQL Server and ADO.NET: Notes on Performance

custTable.AcceptChanges() Appendix A - Relational Databases: Some Basic Concepts RefreshData() Appendix B - Commonly Used SQL Statements End Sub Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables

As you can see, the code adds Name as TextBox4.Text and Address as TextBox4.Text.

List of Listings

List of call Sidebars You NewRow of DataTable to add a new row to DataTable, set its field values, and call the

DataTable.Rows.Add method to add it. After the Add method, you also call DataTable.AcceptChanges method to save the changes. At the end, you call the RefreshData method to fill the DataGrid with the records. If you add six rows to the DataTable using the Add Row button, the result looks like Figure 3-12. The Delete Rows button deletes the records from a column that matches the given criteria. The Remove Rows Section takes a column name and column value, and the Delete Rows button click event handler removes the rows from the DataTable. TheDeleteRowsBtn_Click method is the click event handler for the Delete Rows button (see Listing 3-19). As you can see, the code uses the Select method of DataTable. The Select method of

DataTable takes a criterion and returns the rows that meet the given criteria. In this case, you pass a Applied ADO.NET: Building Solutions column name and its value as a criterion. TheData-Driven Select method returns all the matching rows in an array of ISBN:1590590732 by Mahesh Chand and David Talbot DataRow. Once you've retrieved these rows, you call DataRow.Delete method to delete the rows one © 2003 (928 pages) by one, followed Apress by a call of DataRow.AcceptChanges method to save the changes. This text provides extensive coverage of ADO.NET technology ADO.NET internals, namespaces, classes, and Listing 3-19: Theincluding DeleteRow_Click Method

interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET. Private Sub DeleteRowsBtn_Click(ByVal sender As System.Object, _

ByVal e As System.EventArgs) Handles DeleteRowsBtn.Click Dim str As String = TextBox7.Text + "='" + TextBox6.Text + "'" Table of Contents Dim rows() As DataRow = custTable.Select(str) Applied ADO.NET—Building Data-Driven Solutions ' If no record found Introduction If rows.Length = 0 Then Chapter 1 MessageBox.Show("Record - ADO.NET Basics not found!") Chapter 2 Return - Data Components in Visual Studio .NET ChapterEnd 3 -If ADO.NET in Disconnected Environments ChapterDim 4 -iADO.NET in Connected Environments As Integer ChapterFor 5 -iHandling ADO.NET Events = 0 To rows.Length - 1 Step i + 1 Chapter 6 rows(i).Delete() - Integrating XML with ADO.NET Chapter 7 rows(i).AcceptChanges() - Data Binding and Windows Forms Data-Bound Controls Next Chapter 8 - Constraints and Data Relations ChapterRefreshData() 9 - ADO.NET Exception Handling End Sub Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

In the end, you call the RefreshData method to refresh the grid.


Chapter ADO.NET Xml Web As you 15 can- Using see from Figurein3-13, if youServices enter column name as Name with the value Puneet, then the Chapter - ASP.NET Server Controls and Data Delete 16 Rows button removes the row with Id =Binding 102. Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 3-13: Deleting rows from the DataTable You just saw the usage of the DataTable.Select method, which sorts and filters the DataTable rows. TheSelect method has four overloaded forms. The Select method can take an expression with optional sort and row state parameters. Afilter is a conditional statement that uses the SELECT…WHERE clause to select conditional data from the database. All SQL conditional operators are valid in the filter string. For example, to filter rows where the id is greater than 22, the filter string will be Id>22; for selecting records with the name Ross, the filter string

will be Name='Ross'. The SeachBtn_Click method searches for the criteria you specify on the form. Applied ADO.NET: Data-Driven Solutions As you can see from Listing 3-20, theBuilding code first calls the Select method with the given criteria, which ISBN:1590590732 by Mahesh Chand and David Talbot returns an array of DataRow objects. It creates a new DataTable called searchTable and adds all © 2003 (928 pages)to this DataTable, and it later binds the searchTable to rows returned by Apress the Select method This provides extensive coverage of ADO.NET technology DataGrid to view thetext rows. including ADO.NET internals, namespaces, classes, and

and takes a comprehensive look at XML Listing 3-20: Theinterfaces, SearchButtonClick Method


Private Sub SearchBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles SearchBtn.Click

Table of Contents


Dim searchTable As DataTable = New DataTable("SortTable") searchTable = custTable.Clone() ChapterDim 1 -str ADO.NET Basics As String = TextBox1.Text & " ='" & TextBox2.Text + "'" ChapterDim 2 -rows() Data Components in Visual .NET As DataRow = Studio custTable.Select(str) Chapter'3 If- ADO.NET in Disconnected Environments no record found ChapterIf 4 rows.Length - ADO.NET in Connected Environments = 0 Then Chapter 5 MessageBox.Show("Name - Handling ADO.NET Events not found!") Chapter 6 Return - Integrating XML with ADO.NET ChapterEnd 7 -If Data Binding and Windows Forms Data-Bound Controls Dim i As Integer Chapter 8 - Constraints and Data Relations For i = 0 ToException rows.Length Chapter 9 - ADO.NET Handling - 1 Step i + 1 Dim row As DataRow searchTable.NewRow() Chapter 10 - Working with the ODBC = .NET Data Provider row("Name") = rows(i)("Name") Chapter 11 - Stored Procedures and Views row("Address") = rows(i)("Address") Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers searchTable.Rows.Add(row) Chapter 13 - Developing a Custom Data Provider Next Chapter 14 - Developing Database Web Applications using ASP.NET Dim sortdtSet As DataSet = New DataSet("SortedData") Chapter 15 - Using ADO.NET in Xml Web Services sortdtSet.Tables.Add(searchTable) Chapter 16 - ASP.NET Server Controls and Data Binding DataGrid1.DataSource = sortdtSet.DefaultViewManager Chapter 17 - Building Real-World Web Applications End Sub Introduction

Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter Now using 21 -the Messaging Search Section text boxes, you can search for records with the name Amy by entering

Name in Enter Column Name box,Notes entering Amy in the Enter Value box, and clicking the Search Chapter 22the - SQL Server and ADO.NET: on Performance button. The result looks like Figure 3-14. Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 3-14: Result of clicking the Search button for Name="Amy"

Now using the Select method, you can also sort the data of a DataTable. As you can see from Figure Applied ADO.NET: Building Data-Driven Solutions 3-14, the Sort Section has a DESC check box and an Enter Column Name text box. If the DESC check ISBN:1590590732 by Mahesh Chand and David Talbot box is clicked, rows will be sorted in descending order; otherwise, the default order is ascending. A filter Apress © 2003 (928 pages) followed by values ASC and DESC sorts the rows filtered using the Select method. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Listing 3-21 shows the code written on the Sort button click event handler. As you can see, first the code interfaces, and takes a comprehensive look at XML builds a filter string, checking and whether theand DESC box is both checked. namespaces classes, howcheck to integrate with After that it simply calls the Select method ADO.NET. with the filter string and creates a new DataTable from the rows returned by the

Select method and binds the new DataTable to the grid. Table of Contents Listing 3-21: Sorting Data Using the Select Method Applied ADO.NET—Building Data-Driven Solutions Introduction

Private Sub SortBtn_Click(ByVal sender As System.Object, _ Basics ByVal -eADO.NET As System.EventArgs) Handles SortBtn.Click

Chapter 1 Chapter 2


ChapterDim 3 -sortTable ADO.NET in Disconnected Environments As DataTable = New DataTable("SortTable") ChaptersortTable 4 - ADO.NET Connected Environments = incustTable.Clone() ChapterDim 5 -strSort Handling ADO.NET Events= TextBox3.Text As String ChapterIf 6 (CheckBox1.Checked) - Integrating XML with ADO.NET Then Chapter 7 strSort - Data Binding = strSort and Windows & " Forms DESC" Data-Bound Controls ChapterElse 8 - Constraints and Data Relations

= Exception strSortHandling & " ASC" Chapter 9 strSort - ADO.NET ChapterEnd 10 -If Working with the ODBC .NET Data Provider

As DataRow = _ ChapterDim 11 -rows() Stored Procedures and Views ChaptercustTable.Select(String.Empty, 12 - Oracle, SQLXML, and Other .NET Data strSort) Providers

Dim i As Integer For i = 0 To rows.Length - 1 Step i + 1 Chapter 14 - Developing Database Web Applications using ASP.NET Dim row As DataRow = sortTable.NewRow() Chapter 15 - Using ADO.NET in Xml Web Services row("Name") = rows(i)("Name") Chapter 16 - ASP.NET Server Controls and Data Binding row("Address") = rows(i)("Address") Chapter 17 - Building Real-World Web Applications sortTable.Rows.Add(row) ChapterNext 18 - Object-Relational Mapping in .NET ChapterDim 19 -sortdtSet Mapped Objects: and Data Binding As Performance DataSet =Considerations New DataSet("SortedData") ChaptersortdtSet.Tables.Add(sortTable) 20 - COM Interoperability and ADO.NET ChapterDataGrid1.DataSource 21 - Messaging = sortdtSet.DefaultViewManager Chapter 22 - SQL Server and ADO.NET: Notes on Performance End Sub Chapter 13 - Developing a Custom Data Provider


To sort the records, you enter the column name Name and check the DESC check box. Now, if you click Index theofApply Sort button, you'll see the records are sorted on the name. If you uncheck the DESC check box, List Figures you'll see the rows sorted in ascending order.

List of Tables

List of last Listings The thing to do in this example is to create the Save button. The DataSet class provides methods to List of Sidebars read and write XML documents. The WriteXml method of DataSet saves data to an XML document.

(We discuss XML and ADO.NET in more detail in Chapter 6.) Listing 3-22 shows the Save method button click event handler. As you can see, the code calls a SaveFileDialog and reads the name and path of the file. You can browse the path where you want to save the file. After saving data, if you open the XML file, you'll see all data from the DataTable is stored in this file. Listing 3-22: Saving a DataTable Data in an XML Document Private Sub SaveBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles SaveBtn.Click

Dim fdlg As SaveFileDialog = New SaveFileDialog() Applied ADO.NET: ADO.NET Building Data-Driven fdlg.Title = "Applied Save FileSolutions Dialog" ISBN:1590590732 by Mahesh Chand and David Talbot fdlg.InitialDirectory = "c:\\" Apress © 2003 (928 pages) fdlg.Filter = "XML files (*.xml)|*.*|All files (*.*)|*.*" This text provides extensive coverage of ADO.NET If fdlg.ShowDialog() = DialogResult.OK Then technology including ADO.NET internals, namespaces, classes, and dtSet.WriteXml(fdlg.FileName) interfaces, and takes a comprehensive look at XML End If namespaces and classes, and how to integrate both with End Sub ADO.NET. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

The Row and Column Collections


- ADO.NET Basics

Chapter 7


Do you remember the Rows and Columns property of DataTable? As mentioned earlier, the Columns Chapter 2 - Data Components in Visual Studio .NET property of DataSet, represented by a DataColumnCollection object, stands for all columns of a Chapter 3 - ADO.NET in Disconnected Environmentsrepresents a collection of rows of a DataTable. DataTable. The Rows property of DataTable Chapter 4 ADO.NET in Connected Environments Generally, you access the rows and columns collections through the Rows and Columns properties of a Chapter 5 - Handling Events DataTable. You've ADO.NET already seen how to add columns and rows to a DataTable in the previous sections. Chapter 6 Integrating XML with ADO.NET In the following sections, we discuss the methods and properties. Chapter 8

- Constraints and Data Relations The DataRowCollection Class - ADO.NET Exception Handling

Chapter 9

Chapter 10 - property Working with the ODBC .NET Data Provider TheCount of DataRowCollection returns the total number of rows in a collection. The Chapter 11 code - Stored Procedures Views following reads the total and number of rows in custTable: Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Dim rows As DataRowCollection = custTable.Rows Chapter 14 - Developing Database Web Applications using ASP.NET Dim counter As Integer Chapter 15 -=Using ADO.NET in Xml Web Services counter rows.Count Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

TheClear of DataRowCollection Chapter 18 - method Object-Relational Mapping in .NET removes all the rows in a collection and sets the Rows count to19zero: Chapter - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Dim rows As DataRowCollection = custTable.Rows Chapter 21 - Messaging rows.Clear() Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

TheRemove and RemoveAt methods remove a specified DataRow based on the DataRow and its index, respectively.


The method looks for a primary key value in the collection. This method returns True if a List ofContains Figures collection finds the specified value in the primary key column. The Contains method takes an argument List of Tables of an object type. List of Listings List of Sidebars

TheFind method is one more useful method of DataRowCollection; it searches for a row in the collection. Similar to the Contains method, the Find method also takes an argument of object type, which means Find can be used to find any types of values. Listing 3-23 checks if the row collection's primary key column contains value 1002. If it does, it uses the Find method, which returns a DataRow and calls the DataRowCollection.Remove method to remove the row from the collection. Listing 3-23: Using the Contains,Find, and Remove Method of DataRowCollection Dim rows As DataRowCollection = custTable.Rows Dim row As DataRow

If rows.Contains(1002) Then Applied ADO.NET: Building Data-Driven Solutions row = rows.Find(1002) ISBN:1590590732 by Mahesh Chand and David Talbot rows.Remove(row) Apress © 2003 (928 pages) MessageBox.Show("Row Removed") This text provides extensive coverage of ADO.NET technology Else including ADO.NET internals, namespaces, classes, and MessageBox.Show("Row not found") interfaces, and takes a comprehensive look at XML End If namespaces and classes, and how to integrate both with ADO.NET.

Table of Contents As you saw in earlier sections, the Add method of DataRowCollection adds a new row at the end of a Applied ADO.NET—Building Solutions collection. But what if youData-Driven want to insert a row between two rows? The InsertAt method does the trick Introduction for you and inserts a row at the specified index, and the row at the index becomes the next row. Listing 324 inserts removes rows at the specified index using the InsertAt and RemoveAt methods. Chapter 1 -and ADO.NET Basics Chapter 2


Listing 3-24: Using the InsertAt and RemoveAt Methods - ADO.NET in Disconnected Environments

Chapter 3 Chapter 4


Dim newRow As DataRow Chapter 5 - Handling ADO.NET Events newRow custTable.NewRow() Chapter 6 =- Integrating XML with ADO.NET newRow("id") = 1005 Chapter 7 - Data Binding and Windows Forms Data-Bound Controls newRow("Address") = Data "NewRelations Address" Chapter 8 - Constraints and newRow("Name") "New Name" Chapter 9 - ADO.NET = Exception Handling rows.InsertAt(newRow, 3)


If (Not rows(1).IsNull("id")) Then rows.RemoveAt(1) Chapter 13 - Developing a Custom Data Provider End If

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications The DataColumnCollection Class Chapter 18 - Object-Relational Mapping in .NET

Similar19 to DataRowCollection, the Count property of DataColumnCollection returns the number Chapter - Mapped Objects: Performance Considerations and Data Binding of columns a collection. You already saw in previous samples that you can use the Add method to add Chapter 20 - in COM Interoperability and ADO.NET a new column to a collection. Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

You can use the CanRemove method to find out if a column can be removed from a collection. It returns True if a column can be removed from a collection; otherwise, it returns False. This method performs Appendix B - Commonly Used SQL Statements several operations to make sure the column exists in the table and it's not involved in a constraint or Appendix - ADO.NET Frequently Questions relation. CThe Contains methodAsked checks if a column with a given name exists in the collection. Appendix A - Relational Databases: Some Basic Concepts

Index

The List ofRemove Figures and RemoveAt methods remove a column from a collection. The Remove method takes a parameter List of Tablesof type DataColumn or a name of the column. Listing 3-25 uses some of these methods. List of Listings

Listing 3-25: Removing a Column from a Collection

List of Sidebars

Dim cols As DataColumnCollection = custTable.Columns Dim str As String str = cols.Count.ToString() MessageBox.Show(str) If cols.Contains("Name") Then If cols.CanRemove(cols("Name")) Then cols.Remove("Name") End If End If

Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 TheRemoveAt method by Mahesh removes Chandaand column DavidatTalbot the given index. The Clear method removes all the Apress ©collection. 2003 (928 pages) columns from a column The following codes uses these two methods:

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and cols.RemoveAt(2) interfaces, and takes a comprehensive look at XML cols.Clear() namespaces and classes, and how to integrate both with ADO.NET.

The DataRow States and Versions

Table of Contents


ADataRow changes its states as you work on it. The RowState property of DataRow represents the state of a row, which is a type of DataRowState enumeration. The DataRowState enumeration has five Chapter 1 - ADO.NET Basics members: Introduction Chapter 2


Chapter The 3 Added - ADO.NET state in means Disconnected the row Environments has been added to a collection and the DataRow.AcceptChanges Chapter method 4 - ADO.NET hasn't been in Connected called yet.Environments Chapter 5


Chapter 6


TheDeleted state means the row was deleted using DataRow.Delete.

Chapter 7 Detached - Data Binding Windows Forms Controls The stateand means the row hasData-Bound been created but not added to a collection. Chapter 8 - Constraints and Data Relations

The means the row has been changed, and DataRow.AcceptChanges has not Chapter 9 Modified - ADO.NETstate Exception Handling been yet.with the ODBC .NET Data Provider Chapter 10 called - Working Chapter 11 - Stored Procedures and Views

TheUnchanged state means that DataRow.AcceptChanges has been called but the row wasn't changed.


Chapter 14examine - Developing Database Web Applications using ASP.NET You can the state of a DataRow after any operation on the row. Listing 3-26 uses the RowState Chapter 15to- determine Using ADO.NET in Xml Services property the state of Web a row. Chapter 16 - ASP.NET Server Controls and Data Binding

Listing17 3-26: Determining theWeb State of a Row Chapter - Building Real-World Applications Chapter 18 - Object-Relational Mapping in .NET Chapter Dim row 19 -As Mapped DataRow Objects: Performance Considerations and Data Binding

row =20custTable.NewRow() Chapter - COM Interoperability and ADO.NET MessageBox.Show(row.RowState.ToString()) Chapter 21 - Messaging row("id") = Server 1007 and ADO.NET: Notes on Performance Chapter 22 - SQL row("Name") = "Noak " Appendix A - Relational Databases: Some Basic Concepts row("Address") = Used "Tame NJ" Appendix B - Commonly SQL Lack, Statements custTable.Rows.Add(row) MessageBox.Show(row.RowState.ToString()) Index custTable.Rows.Remove(row) List of Figures custTable.AcceptChanges() Appendix C - ADO.NET Frequently Asked Questions

List of Tables


TheDataRowView is one more important class you should know when working with tables and rows. You can create a DataRowView that corresponds to a DataRow, which you can then bind to data-bound controls directly. ADataRowView class represents a customized view of a DataRow, which can be bound to data-bound controls such as a DataGrid. When you work with a DataRow (update data of a DataRow), the DataRow has different versions. These states are represented by a DataRowVersion enumeration, which has four values: Current,Default,Proposed , and Original. The version of a DataRow changes when you call the BeginEdit,CancelEdit, and EndEdit methods of DataRow as well as theAcceptChanges and RejectChanges methods of DataTable. After calling DataRow.BeginEdit and changing the value of a row, both the Current and Proposed

values become available. After calling DataRow.CancelEdit, the Proposed value isn't available. After Applied ADO.NET: Buildingvalue Data-Driven a call of DataRow.EndEdit, the Current becomesSolutions the Proposed value, and the Proposed ISBN:1590590732 by Mahesh Chand and David Talbot value becomes unavailable. The call of DataRow.AcceptChanges means the original value becomes Apress © 2003 (928 pages) identical to the Current value. A call of DataTable.RejectChanges means the Proposed value is This text provides extensive coverage of ADO.NET technology removed. The version becomes Current. including ADO.NET internals, namespaces, classes, and

interfaces, and takes a comprehensive look at XML TheDataView property of DataRowView class returns a DataView object for a row, which can be namespaces and classes, and how to integrate both with bound to data-bound controls. The IsEdit and IsNew properties represent whether a row is in edit mode ADO.NET. or new mode, respectively. The DataRow property returns the DataRow being viewed, and the RowVersion property returns the version of a row. Table of Contents

TheBeginEdit method Data-Driven starts editingSolutions a row, and the CancelEdit method cancels editing. The Delete Applied ADO.NET—Building method deletes a row, and the EndEdit method ends the editing. Listing 3-27 starts editing a row and later calls the CancelEdit and EndEdit methods, followed by the AcceptChanges method.


- ADO.NET Basics

Chapter - Data Components in Visual Studio .NETCancelEdit, and EndEdit Methods Listing23-27: Editing Rows Using BeginEdit, Chapter 3 - ADO.NET in Disconnected Environments Chapter 4


Dim row As DataRow - Handling ADO.NET Events row = custTable.NewRow() Chapter 6 - Integrating XML with ADO.NET MessageBox.Show(row.RowState.ToString()) Chapter 7 - Data Binding and Windows Forms Data-Bound Controls row("id") = 1007 Chapter 8 - Constraints and Data Relations row("Name") = "Noak " Chapterrow("Address") 9 - ADO.NET Exception Handling = "Tame Lack, NJ" ChaptercustTable.Rows.Add(row) 10 - Working with the ODBC .NET Data Provider ChapterMessageBox.Show(row.RowState.ToString()) 11 - Stored Procedures and Views ChaptercustTable.Rows.Remove(row) 12 - Oracle, SQLXML, and Other .NET Data Providers ChaptercustTable.AcceptChanges() 13 - Developing a Custom Data Provider Chapter 5


Start the Chapter'15 - UsingEditing ADO.NET in Xml Row Web Services ChaptercustTable.Rows(0).BeginEdit() 16 - ASP.NET Server Controls and Data Binding

= 1008 ChaptercustTable.Rows(0)("id") 17 - Building Real-World Web Applications = "New Name" ChaptercustTable.Rows(0)("Name") 18 - Object-Relational Mapping in .NET = "New Address" ChaptercustTable.Rows(0)("Address") 19 - Mapped Objects: Performance Considerations and Data Binding ' Find out DataRowVersion If custTable.Rows(0).HasVersion(DataRowVersion.Proposed) Then Chapter 21 - Messaging MessageBox.Show(DataRowVersion.Proposed.ToString()) Chapter 22 - SQL Server and ADO.NET: Notes on Performance End If Appendix A - Relational Databases: Some Basic Concepts If custTable.Rows(0).HasVersion(DataRowVersion.Original) Then Appendix B - Commonly Used SQL Statements MessageBox.Show(DataRowVersion.Original.ToString()) Appendix C -If ADO.NET Frequently Asked Questions End Index ' Cancel the edit. List of Figures custTable.Rows(0).CancelEdit() List of Tables ' BeginEdit again List of Listings custTable.Rows(0).BeginEdit() List of Sidebars custTable.Rows(0)("id") = 1008 custTable.Rows(0)("Name") = "New Name" custTable.Rows(0)("Address") = "New Address" custTable.Rows(0).EndEdit() custTable.Rows(0).AcceptChanges() DataGrid1.DataSource = custTable Chapter 20 - COM Interoperability and ADO.NET

AppliedDataView, ADO.NET: Building Solutions Using DataSet, andData-Driven DataViewManager by Mahesh Chand and David Talbot

ISBN:1590590732

As you saw in Chapter ADO.NET provides components to view data in data-bound controls. You just Apress2, © 2003 (928 pages) drag and drop controls to a form, set their properties, and bind them to data-bound controls. Then you're This text provides extensive coverage of ADO.NET technology all set to run yourincluding programs. The DataView and DataViewManager ADO.NET internals, namespaces, classes, and classes fall into this category. You interfaces, and takes a comprehensive at XML can use these classes to represent different views of alook DataTable based on different filter and sort and classes, how to integrate with criterion. You cannamespaces use these classes eitherand at design-time or atboth runtime. ADO.NET.

ADataSet is a key component in the ADO.NET data model. It's an in-memory representation of one or multipleDataTables, relations, and constraints. A DataSet stores data from a data source and provides Table of Contents data to the client applications (Web Forms or Windows Forms). A DataSet's contents can be bound to Applied ADO.NET—Building Data-Driven Solutions data-bound controls. (We discuss the DataSet class in more detail in "TheDataSet: The Heart of Introduction ADO.NET." Chapter 1

- ADO.NET Basics

Chapter 2 - DataisComponents Visual Studio .NET TheDataView useful wheninyou need to bind a DataTable or multiple DataTable objects with dataChapter 3 - ADO.NET in Disconnected Environments bound controls. You can also represent multiple views of the same data by applying a filter and sort on a

DataTable, and youincan bind these multiple views to different data-bound controls such as DataGrid, Chapter 4 - ADO.NET Connected Environments DataList, and ListBox Chapter 5 - ComboBox, Handling ADO.NET Events controls. Chapter 6


Figure 3-15 shows the relationship between a DataSet,DataTable,DataView, and Windows and Web - Data Binding and Windows Forms Data-Bound Controls Forms controls. As you can see, a DataSet contains three DataTable objects, which are represented Chapter 8 - Constraints and Data Relations by three different views. You can bind the three different DataView objects to different data-bound Chapter 9 - ADO.NET Exception Handling controls to represent data in different ways. Chapter 7


Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - 3-15: Commonly Used SQLbetween Statements Figure Relationship the DataSet,DataTable, and DataView Appendix C - ADO.NET Frequently Asked Questions Index

The DataSet: The Heart of ADO.NET


ADataSet List of Listingsobject plays a vital role in the ADO.NET component model. A DataSet represents a disconnected List of Sidebars cache of data in the form of tables, rows, columns, or XML schemas. If you've ever programmed a database application in previous versions of VS, you're probably familiar with recordsets. A recordset object was a way to represent data in your programs. Similar to a recordset, a DataSet represents data in your applications. Once you've constructed a DataSet, you can get or set data in your application or your data source. As mentioned earlier, the DataSet works in both connected and disconnected environments. A DataSet communicates with a DataAdapter and calls the DataAdapter'sFill method to fill data from a DataAdapter. You can fill a DataSet object with multiple tables or stored procedures with the aid of the DataAdapters. You'll see how a DataSet works in a connected environment to access data from multiple data sources in the next chapter. In this section, you'll see how it works with DataTable and DataView objects. (We discuss DataAdapter in more detail in Chapter 4.) Once data is filled to a DataSet from a DataAdapter, you can view it in Windows or Web applications by binding data to data-bound controls through a DataView. You can generate one or

multiple views for a DataTables based on the filter and sort criteria.


ISBN:1590590732 Figure 3-16 shows bythe Mahesh relationship Chand and between David DataSet, Talbot DataAdapter, and DataView objects.

Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Figure 3-16: The relationship between DataSet,DataAdapter, and DataView objects Chapter 1 - ADO.NET Basics

As you 2saw earlier, a DataSet can have multiple Chapter - Data Components in Visual Studio .NET DataTable objects. The DataTableCollection object represents all DataSet objects related to a DataSet. The Tables property of the DataSet Chapter 3 - ADO.NET in Disconnected Environments represents collection of DataTable objects. The tables relate to each other with DataRelation Chapter 4 - the ADO.NET in Connected Environments

objects, discussed earlier. DataRelationCollection represents all the available relations in the - Handling ADO.NET Events DataSet. The Relations property represents the DataRelationCollection of a DataSet. A Chapter 6 - Integrating XML with ADO.NET DataSet object stores data in XML format. An XML schema represents a DataSet. A DataSet also Chapter 7 - Data Binding and Windows Forms Data-Bound Controls defines methods to read and write XML documents. The ReadXml method reads an XML document and Chapter 8 - Constraints and Data Relations fills the DataSet with the XML data, and the WriteXML method writes DataSet data to an XML Chapter 9 - ADO.NET Exception Handling document. This class also defines the methods ReadXmlSchema and WriteXmlSchema to read and Chapter 10 - Working with the ODBC .NET Data Provider write XML schema. Chapter 5



Creating a DataSet

Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET TheDataSet class provides three overloaded constructors to create a DataSet object. You create a Chapter 15 Using ADO.NET in Xml Web Services DataSet with or without passing a DataSet name in the DataSet contructor. The following code Chapter - ASP.NET Server Controls and Data Binding creates16 two DataSet objects in different ways: Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Dim dtSet1 As DataSet

Chapter 19 =- Mapped Objects: Performance Considerations and Data Binding dtSet1 New DataSet("DataSet1") Chapter 20 - COMAs Interoperability ADO.NET Dim dtSet2 DataSet = and New DataSet("DataSet2") Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts The DataSet Properties Appendix B - Commonly Used SQL Statements

You justClearned howFrequently to create aAsked DataSet object. In most cases, you'll probably create a DataSet and Appendix - ADO.NET Questions use the DataAdapter'sFill and Update methods to fill and save data from a data source. But the DataSet class provides properties that you can get and set as needed.

Index

List of Figures

List ofCaseSensitive Tables The property indicates whether the string comparison within DataTable objects is case List of Listings sensitive. This property affects how sorting, searching, and filtering operations are performed on List of Sidebarsobjects of a DataSet, when |you use the Select method of DataTable to filter and sort DataTable

data. By default the |CaseSensitive property is False. Use the following to set it to True: DtSet1.CaseSensitive = True

TheDataSetName property represents the name of a DataSet. The following code first sets a DataSet name and then displays it in a message box: Dim dtSet1 As DataSet dtSet1 = New DataSet("DataSet1") dtSet1.DataSetName = "CustomDataSet"

MessageBox.Show(dtSet1.DataSetName.ToString()) Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

TheDefaultViewManager (readextensive only) property returns a custom view of the data of a DataSet. (We This text provides coverage of ADO.NET technology including internals, namespaces, classes, and discuss this in more detailsADO.NET in "The DefaultViewManager.") interfaces, and takes a comprehensive look at XML namespaces and classes, how totype integrate bothwhich with makes sure constraint rules are TheEnforceConstraints property is aand Boolean property, ADO.NET. followed when data of a DataSet is being updated. The default value of the EnforceConstraints property is True. If you don't want the Update method to check the constaints, just set this property as False. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Do you remember the ExtendedProperties property of the DataTable? The ExtendedProperties property attaches some additional custom information about a DataTable. Chapter - ADO.NET Basics the DataSet also provides the ExtendedProperties property. Listing 3-28 Similar1to the DataTable, Chapter 2 reads - Datathe Components in Visual of Studio .NET sets and custom properties a DataSet. Introduction

Chapter 3

- ADO.NET in Disconnected Environments Listing43-28: Settinginand Reading Custom Properties of a DataSet Chapter - ADO.NET Connected Environments Chapter 5


Chapter 6 - Integrating XML with ADO.NET Dim dtSet1 As DataSet Chapter 7 =- Data and Windows Forms Data-Bound Controls dtSet1 New Binding DataSet("DataSet1") Chapter 8 - Constraints and=Data Relations dtSet1.DataSetName "CustomDataSet" Chapter 9 - ADO.NET Exception Handling dtSet1.ExtendedProperties.Add("Description", "The Name Column") Chapter dtSet1.ExtendedProperties.Add("Author", 10 - Working with the ODBC .NET Data Provider "Mahesh Chand")

dtSet1.ExtendedProperties.Add("UserId", "MCB") Chapter 11 - Stored Procedures and Views dtSet1.ExtendedProperties.Add("PWD", "Password") Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers ' Remove Author property Chapter 13 - Developing a Custom Data Provider dtSet1.ExtendedProperties.Remove("Author") Chapter 14 - Developing Database Web Applications using ASP.NET ' Read properties Chapter 15 custom - Using ADO.NET in Xml Web Services Dim str As String Dim i As Integer Chapter 17 - Building Real-World Web Applications str = dtSet1.ExtendedProperties("Description").ToString() Chapter 18 - Object-Relational Mapping in .NET str = str + ", " + dtSet1.ExtendedProperties("UserId").ToString() Chapter 19 - Mapped Objects: Performance Considerations and Data Binding str = str + ", " + dtSet1.ExtendedProperties("PWD").ToString() Chapter 20 - COM Interoperability and ADO.NET MessageBox.Show(str) Chapter 16 - ASP.NET Server Controls and Data Binding

Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix TheHasErrors B - Commonly property Used finds SQLout Statements if any of the rows of a DataSet has any errors. The DataTable also Appendix providesCthis - ADO.NET propertyFrequently to check ifAsked a particular Questions row has any errors. (We show you how to use this property in

a moment.) Index List of Figures

ACultureInfo object contains the data about a machine locale. The Locale property gets and sets this data. The following code uses this property to read the information:

List of Tables

List of Listings

List of Sidebars

Dim cInfo As System.Globalization.CultureInfo cInfo = dtSet1.Locale Console.WriteLine(cInfo.DisplayName, cInfo.EnglishName)

As mentioned earlier (and in more detail in Chapter 6), a DataSet is represented by an XML schema, which has a namespace and prefix. The Namespace and Prefix properties represent the namespace and prefix of the schema, respectively. These properties are both readable and writeable: dtSet1.Namespace = "CustDSNamespace" dtSet1.Prefix = "CustPrefix"


TheRelations by property returns collection of relations that aISBN:1590590732 DataSet has. (We discuss this property Mahesh Chandaand David Talbot in later sections and Apress in Chapter © 2003 (928 4.)pages) This text provides extensive coverage of ADO.NET technology

As discussed earlier, the Tables ofnamespaces, a DataSet classes, represents including ADO.NETproperty internals, anda collection of DataTables attached to a DataSet. The Tablesand property of type DataTableCollection, which was discussed earlier. interfaces, takes aiscomprehensive look at XML namespaces and classes, and how to integrate with TheDataTableCollection class provides methods to add both and remove DataTable objects to a ADO.NET. collection.

Attaching a DataTable Table of Contents

to a DataSet


You've already seen how to create a DataTable and add columns and rows to a DataTable by using

Introduction theDataRow and DataColumn. As mentioned earlier, a DataSet is a collection of DataTable objects. Chapter 1 - ADO.NET TheTables propertyBasics of DataSet gets all the attached DataTables of a DataSet. The Tables Chapter 2 which - DataisComponents in Visual Studio .NET property, a type of DataTableCollection, also adds DataTable objects to a DataSet and Chapter 3 them. - ADO.NET Disconnected Environments removes Listingin3-29 creates four DataTable objects and adds them to a DataSet using the Chapter 4 - ADO.NET in Connected DataSet.Tables.Add method. Environments The DataSet is bound to a DataGrid to view the contents in a Chapter DataGrid. 5 - Handling ADO.NET Events Chapter 6


Listing73-29: Adding DataTable Objects a DataSet Chapter - Data Binding and Windows Formsto Data-Bound Controls Chapter 8


Chapter Dim tbl1 9 - ADO.NET As DataTable Exception =Handling New DataTable("One")

Dim tbl2 As DataTable = New Chapter 10 - Working with the ODBC .NETDataTable("Two") Data Provider Dim tbl3 As DataTable = New Chapter 11 - Stored Procedures and ViewsDataTable("Three") Dim dtSet1 As SQLXML, DataSetand = Other New .NET DataSet("CustDtSet") Chapter 12 - Oracle, Data Providers dtSet1.Tables.Add(custTable) Chapter 13 - Developing a Custom Data Provider dtSet1.Tables.Add(tbl1) Chapter 14 - Developing Database Web Applications using ASP.NET dtSet1.Tables.Add(tbl2) dtSet1.Tables.Add(tbl3) Chapter 16 - ASP.NET Server Controls and Data Binding DataGrid1.DataSource = dtSet1.DefaultViewManager Chapter 15 - Using ADO.NET in Xml Web Services


Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET In this code, custTable is a DataTable created using the methods discussed. Chapter 21 - Messaging

The output Listing 3-29 like Figure If you click a DataTable link, you can see the data of Chapter 22 - of SQL Server andlooks ADO.NET: Notes 3-17. on Performance theDataTable (if it has any). Some Basic Concepts Appendix A - Relational Databases: Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7 - 3-17: Data Binding and Windows Forms Figure Attaching DataTables to aData-Bound DataSet Controls Chapter 8 - Constraints and Data Relations Chapter 9


Copying, Cloning, Clearing DataSets Chapter 10 - Working with and the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

TheClear method removes all the rows from a DataSet; however, it does not destroy the structure of a DataSet. The Copy method copies the contents with schema of a DataSet to another DataSet. The Chapter 13 - Developing a Custom Data Provider Clone method only copies the structure of a DataSet to another. Listing 3-30 uses all three members. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


Chapter - Using ADO.NET in Xml Web Listing15 3-30: Using Copy,Clone, andServices Clear Methods of DataSet Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

Dim dtSet1 As DataSet = New DataSet("CustDtSet")

Chapter 18 - Object-Relational Mapping in .NET dtSet1.Tables.Add(custTable) Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Dim dtSet2 As DataSet = New DataSet() Chapter 20 =- COM Interoperability and ADO.NET dtSet2 dtSet1.Clone() Chapter 21 =- Messaging dtSet2 dtSet1.Copy() Chapter 22 - SQL Server and ADO.NET: Notes on Performance dtSet1.Clear() Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Getting Index

Changed Rows of a DataSet

List of Figures

So far, we've talked about filling data from a DataAdapter to a DataSet and saving data back to a data source using the Update method of DataSet. The Update method takes a DataSet and saves its List of Listings results in a data source. A DataAdapter belongs to a data provider, so we discuss it in Chapter 4. List of Tables

List of Sidebars

TheGetChanges method helps you find the changed data of a DataSet so you can send only changed data back to the data source instead of sending an entire DataSet. It helps to reduce the network traffic and make the save process faster. TheGetChanges method returns a DataSet, which contains all the changes made to a DataSet since it was last loaded or the AcceptChanges method was called. TheGetChanges method has two overloaded forms. The first form takes no parameters and returns all the results. The second form lets you filter the results based on the row states, and it takes a parameter of typeDataRowState. TheHasChanges method determines if a DataSet has any changes since it was last saved or loaded.

The following snippet shows how to use the HasChanges and GetChanges methods (you'll see these methods in moreApplied detail in ADO.NET: Chapter 4).Building Data-Driven Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

If Not dtSet1.HasChanges(DataRowState.Modified) Then Exit Sub This text provides extensive coverage of ADO.NET technology Dim dtSet2 Asincluding DataSet ADO.NET internals, namespaces, classes, and dtSet2 = dtSet1.GetChanges(DataRowState.Modified) interfaces, and takes a comprehensive look at XML SqlDbDataAdapter1.Update(dtSet2) namespaces and classes, and how to integrate both with ADO.NET.

Merging a DataRow, DataTable, or a DataSet

Table of Contents

Applied ADO.NET—Building Data-Driven Solutions TheMerge method merges two DataSet objects and saves the results in one DataSet. The Merge Introduction method has seven overloaded forms. These forms allow you to merge a DataRow, a DataTable, and a Chapter 1 -with ADO.NET Basics DataSet an existing DataSet. The first parameter of the Merge method is a DataRow, Chapter 2 - Data Components in Visual .NETparameter is a Boolean type-a True value indicates that DataTable, or DataSet. The secondStudio optional Chapter the changes 3 - ADO.NET should be in Disconnected preserved and Environments False indicates that changes won't be preserved. The third

optional4 parameter a Connected type of MissingSchemaAction, which indicates what action should be taken Chapter - ADO.NETisin Environments when the of ADO.NET added DataRow, Chapter 5 schema - Handling Events DataTable, or DataSet does not match the schema of the current6DataSet. The MissingSchemaAction enumeration has four values: Add,AddWithKey, Chapter - Integrating XML with ADO.NET Error,7and Ignore. The Add value adds columns Chapter - Data Binding and Windows Formsnecessary Data-Bound Controlsto complete the schema. The AddWithKey value adds necessary Chapter 8 - Constraints andthe Data Relationsinformation with a primary key. The Error value generates an error. The -Ignore value ignores the extra columns. ADO.NET Exception Handling

Chapter 9

Chapter - Working the ODBC .NET Data Provider Listing 10 3-31 merges with two DataSet objects. The custTable and ordersTables are two DataSet Chapter 11 Stored Procedures and Views objects created by the CreateCustomersTable() and CreateOrdersTable() methods, as Chapter 12 -inOracle, SQLXML, The and Other Data Providers discussed "The DataSet: Heart .NET of ADO.NET" section. Chapter 13 - Developing a Custom Data Provider

Listing14 3-31: MergingDatabase Two DataSetse Chapter - Developing Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls andDataSet("EmpDataSet") Data Binding Dim dtSet1 As DataSet = New Chapter 17 - Building Real-World=Web Applications Dim dtSet2 As DataSet New DataSet("OrdersDataSet") Chapter 18 - Object-Relational Mapping in .NET dtSet1.Tables.Add(custTable) Chapter dtSet2.Tables.Add(ordersTable) 19 - Mapped Objects: Performance Considerations and Data Binding

dtSet1.Merge(dtSet2, False, MissingSchemaAction.Add) Chapter 20 - COM Interoperability and ADO.NET DataGrid1.DataSource = dtSet1.DefaultViewManager Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

As mentioned, the Merge method also lets you merge an array of a DataRow or a DataTable object. Listing 3-32 shows you how to merge rows and a DataTable with a DataSet.


List of Figures Listing 3-32: MergingDataRow and DataTable Objects List of Tables List of Listings

Dim str As String = "OrderId >= 2 " Dim rows() As DataRow = ordersTable.Select(str) dtSet1.Tables.Add(custTable) dtSet2.Tables.Add(ordersTable) dtSet1.Merge(rows) dtSet1.Merge(ordersTable, True, MissingSchemaAction.Ignore)

List of Sidebars

Other DataSet Methods There are a few more DataSet methods left to discuss. The AcceptChanges method saves all the changes made to a DataSet since it was loaded or the last time AcceptChanges was called. The

RejectChanges method rolls back all the changes made to a DataSet since it was created or the last Applied ADO.NET: Building Data-Driven Solutions timeAcceptChanges was called. These methods are discussed in more details in next chapter. by Mahesh Chand and David Talbot

ISBN:1590590732

TheReadXml andApress ReadXmlSchema © 2003 (928 pages) methods read an XML document and XML schema document, respectively. TheThis WriteXml and WriteXmlSchema methods save DataSet data to XML document and text provides extensive coverage of ADO.NET technology includingrespectively. ADO.NET internals, namespaces, classes, and XML schema document, (We discuss these methods in Chapter 6 in more detail.) interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Typed and Untyped DataSets

As you may recall from earlier discussions, there are two kinds of a DataSet: typed or untyped. A typed Table of Contents DataSet first comes from the DataSet class and then uses an XML schema (.xsd file) to generate a Applied ADO.NET—Building Solutions new class. You saw how Data-Driven to create a typed DataSet using VS .NET in Chapter 2. An untyped DataSet Introduction has no built-in schema. You create an instance of a DataSet class and call its methods and properties to Chapter 1 the - ADO.NET Basics All elements of an untyped DataSet are collections. In this chapter, you'll work with data sources. Chapter work with 2 untyped - Data Components DataSets.in Visual Studio .NET Chapter 3


Both kinds-of DataSet have their own advantages and disadvantages. Typed DataSets take less time to ADO.NET in Connected Environments write applications but offer no flexibility. They're useful when you already know the schema of a database. Chapter 5 - Handling ADO.NET Events The biggest advantage of typed DataSets is the VS .NET IDE support. As you saw in Chapter 2, you can Chapter 6 - Integrating XML with ADO.NET drag a database table, its columns, or stored procedures to a form in your application, and the IDE Chapter 7 - Data Binding and Windows Forms Data-Bound Controls generates typed DataSet for you. After that, you can bind these DataSets to the controls. However, Chapter 8 - Constraints and Data Relations there are many occasions when you don't know the schema of a database. In those cases, the untyped Chapter 9 - are ADO.NET Handling DataSets useful.Exception The untyped DataSets also provide the flexibility of connecting with multiple data Chapter 10 Working with the ODBC .NET Data Provider sources. And you can use them without the VS .NET IDE. Chapter 4


The DataView

Chapter 13 - Developing a Custom Data Provider Chapter - Developing Database Web Applications using ASP.NET Another14powerful feature of ADO.NET is the ability to create several different views of the same data. You Chapter 15 Using ADO.NET in Xml Web Services can sort these views differently and filter them on different criteria. They can contain different row state Chapter 16 - ASP.NET Server Controls and Data Binding information. Chapter 17 - Building Real-World Web Applications

ADataView represents a customized Chapter 18 - Object-Relational Mapping inview .NETof DataTable that you can bind to Windows Forms and Web Forms 19 controls. Using DataView sort and filter features, you canBinding also have multiple views of a single Chapter - Mapped Objects: Performance Considerations and Data

DataTable. Using RowFilter and Sort properties, you can apply a filter on a DataView and sort its contents before binding it to a data-bound control. The AddNew method adds a new row to a DataView, Chapter 21 - Messaging and the Delete method deletes a row from a DataView. You can use the Find and FindRows Chapter 22 - SQL Server and ADO.NET: Notes on Performance methods to search for rows based on the defined criteria. Chapter 20 - COM Interoperability and ADO.NET


Appendix B -describes Commonly Usedof SQL Table 3-9 some theStatements DataView properties, and Table 3-10 describes some of its methods. Appendix C - ADO.NET Frequently Asked Questions Index Table 3-9: The DataView Class Properties List of Figures List of Tables List of Listings List of Sidebars

PROPERTY

DESCRIPTION Applied ADO.NET: Building Data-Driven Solutions

AllowDelete

ISBN:1590590732 by Mahesh Chand and David Talbot Indicates whether deletes are allowed. Apress © 2003 (928 pages)

This text provides Indicates extensive whethercoverage edits areofallowed. ADO.NET technology including ADO.NET internals, namespaces, classes, and AddNews new rowslook canatbeXML added. interfaces, Indicates and takeswhether a comprehensive namespaces and classes, and how to integrate both with ApplyDefaultSort ADO.NET. Indicates whether to use default sort. True means use the default sort

AllowEdit

andFalse means no. Represents the number of records in a DataView after RowFilter andRowStateFilter have been applied. Applied ADO.NET—Building Data-Driven Solutions

Count Table of Contents

Introduction DataViewManager Chapter 1

Item

Chapter 2

DataViewManager associated with this view.

- ADO.NET Basics

Represents an item of a row. - Data Components in Visual Studio .NET

Chapter 3 - ADO.NET in Disconnected Environments RowFilter Represents the expression used to filter rows to view in the DataView. Chapter 4 - ADO.NET in Connected Environments

RowStateFilter

You can use a row state filter using this property.

Chapter 5


Chapter Sort6 Chapter 7

- Integrating XML Represents with ADO.NET the sort column and sort order. - Data Binding and Windows Forms Data-Bound Controls

Chapter 8


Chapter 9


Table

DataTable attached with this view.


Table 3-10: The DataView Class Methods


Chapter METHOD 12 - Oracle,DESCRIPTION SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

AddNew

Adds a new row to the DataView

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter BeginInit 15 - Using Begins ADO.NET Xml Web Services theinintialization if a data view was previously used Chapter 16 - ASP.NET Server Controls and Data Binding

EndInit

Ends the initialization started by BeginInit


Delete Chapter 18 - Object-Relational Deletes a row Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Find

Finds a row in the DataView based on the specified criteria


FindRows Returns an array of rows based on the specified criteria Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Creating a DataView Appendix B - Commonly Used SQL Statements


TheDataView constructor allows you to create a DataView object from a DataTable, which you can use with or without a DataSet. In Listing 3-33, the custTable and ordersTable are two DataTable List of Figures objects. As you can see, the code creates a DataView directly from a DataTable and creates a second List of Tables through a DataSet. DataView Index

List of Listings

Listing 3-33: CreatingDataView Objects from a DataTable List of Sidebars ' Creating a DataView from DataTable Dim dtView1 As DataView = New DataView(custTable) ' Creating a DataView through DataSet Dim dtSet1 As DataSet = New DataSet() dtSet1.Tables.Add(ordersTable) Dim dtView2 As DataView = New DataView(dtSet1.Tables(0))

Binding a DataView with a data-bound control is pretty easy. You set the DataSource and

DisplayMember properties of a data-bound control. For example, the following code binds two Applied Data-Driven Solutions DataView objects with a ADO.NET: DataGridBuilding and a ListBox control. by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

DataGrid1.DataSource = dtView1 This text provides extensive coverage of ADO.NET technology ListBox1.DataSource = dtView2 including ADO.NET internals, namespaces, classes, and ListBox1.DisplayMember = "Name" interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Chapter 7 discusses data-bound controls in more detail. Table of Contents

Adding, Editing, and Deleting Data Using DataView

Applied ADO.NET—Building Data-Driven Solutions Introduction

TheAddNew method of a DataView, which returns a DataRowView, adds a new row to the DataView. - ADO.NET Basics TheAddNew method is followed by a call of EndEdit. The BeginEdit and EndEdit pair edits the Chapter Data The Components in VisualAllowNew, Studio .NET and AllowEdit properties allow deleting, adding, and values 2of a- row. AllowDelete, Chapter 3 in- a ADO.NET in Disconnected updating DataView if they're setEnvironments to True. Chapter 1

Chapter 4

- ADO.NET in Connected Environments TheDelete method ADO.NET of a DataView Chapter 5 - Handling Events deletes a row specified by the index of the row. The Count property

returns6the- total number of rows in a DataView. Chapter Integrating XML with ADO.NET Chapter 7


Chapter 9


Listing 3-34 uses the previously discussed methods and properties to add, delete, and edit rows of a Chapter 8 - Constraints and Data Relations DataView. Chapter - Working with the ODBCand .NETDeleting Data Provider Listing10 3-34: Adding, Updating, Rows of a DataView Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

' Creating a DataView from DataTable Dim dtView1 As DataView = New DataView(custTable) Chapter 14 - Developing Database Web Applications using ASP.NET ' Creating a DataView through DataSet Chapter 15 Using ADO.NET in Xml Web Services Dim dtSet1 As DataSet = New DataSet() Chapter 16 - ASP.NET Server Controls and Data Binding dtSet1.Tables.Add(ordersTable) Chapter 17 - Building Dim dtView2 As Real-World DataViewWeb = Applications New DataView(dtSet1.Tables(0)) Chapter - Object-Relational Mapping inand .NET AllowEdit to true ' Set18AllowDelete, AllowNew Chapter dtView1.AllowDelete 19 - Mapped Objects:=Performance True Considerations and Data Binding dtView1.AllowNew = True and ADO.NET Chapter 20 - COM Interoperability dtView1.AllowEdit = True Chapter 21 - Messaging ' Edit row Chapter 22 the - SQLdata Serverof andfirst ADO.NET: Notes on Performance dtView1(0).BeginEdit() Appendix A - Relational Databases: Some Basic Concepts dtView1(0)("Name") = SQL "Edited Name" Appendix B - Commonly Used Statements dtView1(0)("Address") = "Edited Address" Appendix C - ADO.NET Frequently Asked Questions dtView1(0).EndEdit() Index ' Delete the first row from DataView List of Figures ' the Delete method takes an index of row starting List of Tables ' at 0 List of Listings If dtView1.AllowDelete Then List of Sidebars dtView1.Delete(0) End If ' Add a new row Dim drv As DataRowView = dtView1.AddNew ' Change values in the DataRow. drv("id") = 1010 drv("Name") = "New Name" drv("Address") = "New Address" drv.EndEdit() ' Count number of rows MessageBox.Show(dtView1.Count.ToString()) Chapter 13 - Developing a Custom Data Provider

Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Searching and Sorting Data Using DataView

ISBN:1590590732


Searching and sorting areprovides two major operations that aofDataView does to filter data. The Sort property of This text extensive coverage ADO.NET technology internals, namespaces, DataView sorts including rows of aADO.NET DataView. The Sort propertyclasses, takes aand string value, which contains the sort interfaces, and takes a comprehensive look at XML by a comma (,) and followed by ASC criteria with one or more than one DataTable columns separated namespaces and classes, and how to integrate both with or DESC, where ASC is for sorting rows in ascending order and DESC for sorting rows in descending ADO.NET. order. The following code shows how to use one or more than one column with the ASC and DESC options: Table of Contents Applied ADO.NET—Building Data-Driven Solutions dtView1.Sort = "Name, Address ASC" Introduction dtView1.Sort = "Name DESC" Chapter 1 - ADO.NET Basics Chapter 2

- Data Components in Visual Studio .NET TheRowFilter property of a DataView filters the rows depending on the given criteria. The Chapter 3 - ADO.NET in Disconnected Environments

RowFilter takes a criteria, whichEnvironments contains columns and their values. The following code returns all rows Chapter 4 - ADO.NET in Connected that contain Name column values of Miranda: Chapter 5 - Handling ADO.NET Events Chapter 6


dtView1.RowFilter = "Name = Forms 'Miranda'" Chapter 7 - Data Binding and Windows Data-Bound Controls Chapter 8


Chapter 9


Besides the Sort and RowFilter properties, the DataView class provides Find and FindRow methods to find rows. The Find method requires a Sort field and takes a parameter of type Object or Chapter 11of- Object. Stored Procedures and Views an array The FindRow method returns an array of DataRowView, whose column matches Chapter 12 Oracle, SQLXML, and Other .NET Data Providers the specified sort key value. Chapter 10 - Working with the ODBC .NET Data Provider


Listing 14 3-35 uses the Find method find the value "Data Quest" in the column Name, which returns an Chapter - Developing Database WebtoApplications using ASP.NET index of15the row. ADO.NET in Xml Web Services Chapter - Using Chapter 16 - ASP.NET Server Controls and Data Binding

Listing 3-35: Finding Rows in a DataView Using the Find Method


' Creating a DataView from DataTable Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Dim dtView1 DataView and = New DataView(custTable) Chapter 20 - COM As Interoperability ADO.NET ' Creating a DataView through DataSet Chapter 21 - Messaging Dim dtSet1 As DataSet = New DataSet() dtSet1.Tables.Add(ordersTable) Appendix A - Relational Databases: Some Basic Concepts Dim dtView2 As DataView = New DataView(dtSet1.Tables(0)) Appendix B - Commonly Used SQL Statements dtView2.Sort = "Name" Appendix C - ADO.NET Frequently Asked Questions Dim val As Object = "Data Quest" Index Dim pos As Integer = dtView2.Find(Val) List of Figures MessageBox.Show(pos.ToString()) Chapter 22 - SQL Server and ADO.NET: Notes on Performance


The DataViewManager ADataViewManager contains a collection of views of a DataSet-one view for each DataTable in the DataSet. The DataViewManager has a DataViewSettings property that enables the user to construct a different view for each DataTable in the DataSet. If you want to create two views on the same DataTable, you need to create another instance of the DataViewManager and construct the DataViewSettings for that particular view. Then you construct a DataView using the DataViewManager. For example, in the Orders DataSet, you may want to filter out the orders with an EmployeeID of 4 and sort the orders by the date they were shipped. You can retrieve records for EmployeedId = 4 sorted on the date they were shipped using the sort and filter properties of the DataSet and attaching the filtered and sorted data to a DataView or a DataViewManager.

To construct a DataViewManager, you can either use the Solutions Default constructor or pass in a DataSet Applied ADO.NET: Building Data-Driven object. For example: ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

view = new DataViewManager () This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML or, for example: namespaces and classes, and how to integrate both with ADO.NET.

view = new DataSetView(myDataSet) Table of Contents Applied ADO.NET—Building Data-Driven Solutions

TheDataViewManager has a few properties you need to know about to utilize it effectively. Table 3-11 Introduction shows the properties. Chapter 1 -main ADO.NET Basics Chapter 2


Chapter 3


Table 3-11: DataSetView Properties

Chapter 4 - ADO.NET in Connected Environments PROPERTIES DESCRIPTION Chapter 5


DataSet- Integrating XML The DataSet being viewed of type DataSet. with ADO.NET Chapter 7 - Data Binding andContains Windowsthe Forms Data-Bound Controls objects for each table in the DataViewSettings collection of TableSetting Chapter 8 - Constraints and DataSet. Data Relations The TableSetting object contains sorting and filtering criteria Chapter 9 - ADO.NET Exception for aHandling particular table. Chapter 6


DataViewManager contains and the Views CreateDataView method, which allows you to create a DataView Chapter 11 - Stored Procedures object for particular table inand your DataSet. You can construct the DataView for the table with the Chapter 12 a - Oracle, SQLXML, Other .NET Data Providers DataViewManager's Chapter 13 - DevelopingDataViewSettings a Custom Data Providerfor the particular DataTable of the DataSet. You can also adjust settings for the DataView by assigning filter andASP.NET sort properties directly in the DataView. Chapter 14 - Developing Database Web Applications using Chapter 15 - Using ADO.NET in Xml Web Services

You'll see DataView and DataViewManager objects in the sample applications in Chapter 4.

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET


Summary


ISBN:1590590732

In this chapter you learned about ADO.NET model class hierarchy. ADO.NET consists of three Apress © 2003 (928 the pages) general namespaces and many data provider namespaces. There are two general namespacesThis text provides extensive coverage of ADO.NET technology System.Data and System.Data.Common-and a SQL Server-specific namespace called including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML System.Data.SqlTypes. The System.Data namespace defines classes that are the basic building namespaces and classes, and how to integrate both with clocks of the ADO.NET model. The System.Data.Common namespace defines classes shared by all ADO.NET. data providers. The System.SqlTypes namespace defines classes that convert from SQL native data types to .NET data types. Table of Contents

You can divide ADO.NET classes into two categories: disconnected and connected. You can use disconnected classes with or without data providers, but connected classes work with the data providers. Introduction Some of the disconnected classes are DataSet,DataTable,DataRow,DataColumn,DataView, and Chapter 1 - ADO.NET Basics DataViewManager. Applied ADO.NET—Building Data-Driven Solutions

Chapter 2


Chapter 3 - ADO.NET in Disconnected In this chapter, you saw how to work Environments with these disconnected classes. You learned how to create inmemory with the help of theEnvironments DataTable,DataRow, and DataColumn classes. After that you Chapter 4 tables - ADO.NET in Connected

worked5with the DataView, DataSet, Chapter - Handling ADO.NET Events and DataViewManager classes. Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 4 covers the ADO.NET data providers and working with ADO.NET in a connected environment.


ADO.NET: Building Data-Driven Solutions Chapter Applied 4: ADO.NET in Connected Environments ISBN:1590590732 by Mahesh Chand and David Talbot

Overview


This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and As mentioned earlier, interfaces, you can anddivide takes ADO.NET a comprehensive functionality look atinto XMLtwo categories: connected and andexamined classes, and to integratefunctionality both with provided by the .NET Framework disconnected. In namespaces Chapter 3, you thehow disconnected ADO.NET. that resides in the System.Data and System.Data.Common namespaces. In disconnected

environments, the data is stored in memory. Table of Contents

In this chapter, we explain ADO.NET functionality in connected environments, which means reading and storing data in data sources. Specifically, you access data from a data source and save data back to the Introduction data source with the help of a bridge between the application and the data source; in ADO.NET this bridge Chapter 1 provider. - ADO.NET Basics provides many data providers for different data sources to make data access is a data ADO.NET Chapter 2 - Data Visualdata Studio .NET has data components (classes) that let you connect to a fast, reliable, andComponents easy to use.inEach provider Chapter 3 - ADO.NET in Disconnected Environments data source, as well as read, write, add, delete, and update data. In this chapter, you'll learn about these Chapter 4 - ADO.NET components and howintoConnected work withEnvironments them. Applied ADO.NET—Building Data-Driven Solutions

Chapter 5

- Handling ADO.NET Events So what the ADO.NET Chapter 6 are - Integrating XML data with providers? ADO.NET Technically, an ADO.NET data provider is a set of classes that

enables7 you to connect a data source in order to readControls and write data from a data source. A data Chapter - Data Binding to and Windows Forms Data-Bound

provider also has components that serve as conduits between the data source and the DataSet. In this - Constraints and Data Relations way, the architecture isolates the manipulation of data from the data source.

Chapter 8 Chapter 9



Appliedthe ADO.NET: Building Data-Driven Solutions Understanding Generic Data Provider Model by Mahesh Chand and David Talbot

ISBN:1590590732

Let's examine a generic Apress ©data 2003 provider (928 pages)model before looking at specific data providers. Figure 4-1 shows a generic class model of a data provider. The coverage same component model applies to all of the data providers, This text provides extensive of ADO.NET technology with minor changes. All data providers implement a similar class hierarchy model, so once you're including ADO.NET internals, namespaces, classes, and and takesyou a comprehensive look at XML comfortable with interfaces, one data provider, can easily manipulate the other data providers in no time. It's namespaces and the classes, how to integrate both withstring. usually just a matter of changing classand names and the connection ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Figure A generic data provider model Chapter 13 - 4-1: Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml TheConnection component of aWeb dataServices provider is the first component, and it communicates with a data Chapter - ASP.NET Serversits Controls andaData Binding source.16 A DataAdapter between DataSet and the data source and passes data back and forth. Chapter TheDataAdapter's 17 - Building Real-World Fill method Web fills Applications data from a data source to a DataSet, and the Update method

of the DataAdapter saves changes from a DataSet to a data source. In Chapter 3, you saw how to use Chapter 18 - Object-Relational Mapping in .NET the data you have it in aPerformance DataSet through the DataTable, DataRow, and DataColumn objects. Chapter 19once - Mapped Objects: Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

TheCommand and CommandBuilder objects are two more important components of a data provider. A Command component uses SQL queries to transfer data back and forth from a data source to an Chapter 22 - SQL Server and ADO.NET: Notes on Performance application and vice versa. A Command or CommandBuilder object can use a DataAdapter or a Appendix A - Relational Databases: Some Basic Concepts DataReader. The DataReader is a fast, read-only gateway of data. Chapter 21 - Messaging


Appendix C - ADO.NET Frequently Asked You'll begin your understanding of the Questions ADO.NET data providers by examining the Sql data provider defined in the System.Data.SqlClient namespace. This name-space contains the classes necessary Index

to manipulate List of Figures the data providers. List of Tables List of Listings List of Sidebars

ADO.NET: Building Data-Driven Solutions Importing aApplied Namespace by Mahesh Chand and David Talbot

ISBN:1590590732

Before anything else, you need to pages) decide what data provider you'll use in your applications. Once you've Apress © 2003 (928 decided, you need to include the namespace in your applications so the namespace objects are available This text provides extensive coverage of ADO.NET technology to you. You include a namespace by adding an Imports directive, followed by the namespace, to your including ADO.NET internals, namespaces, classes, and interfaces, and takes comprehensive System.Data.Common, look at XML project. The following lines import theaSystem.Data, namespaces and and how to integrate both with of ADO.NET: System.Data.SqlClient, andclasses, System.Data.OleDb namespaces ADO.NET.

Imports System.Data Table of Contents Imports System.Data.Common Applied ADO.NET—Building Data-Driven Solutions Imports System.Data.SqlClient Introduction Imports System.Data.OleDb Chapter 1

- ADO.NET Basics

Chapter 2


In later chapters, we discuss other data providers-such as Odbc and Oracle- and their related - ADO.NET in Disconnected Environments namespaces.

Chapter 3 Chapter 4


Chapter 5 also - Handling Events objects by specifying the full namespace when you declare the You can accessADO.NET a namespace's Chapter 6 Integrating XML with ADO.NET objects. For example, the following code accesses the SqlConnection class of the Chapter 7 - Data Binding and Windows Forms Controls System.Data.SqlClient namespace (inData-Bound this case, you don't need to use the Imports statement): Chapter 8 - Constraints and Data Relations Chapter 9 - ADO.NET Exception Handling Dim conn As SqlConnection = New SqlClient.SqlConnection() Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

The previous code SQLXML, is equivalent the .NET following Chapter 12 - Oracle, and to Other Data code: Providers Chapter 13 - Developing a Custom Data Provider Chapter Imports 14 -System.Data.SqlClient Developing Database Web Applications using ASP.NET

Dim conn As SqlConnection = Services New SqlConnection() Chapter 15 - Using ADO.NET in Xml Web Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions Exploring the System.SqlClient Namespace by Mahesh Chand and David Talbot

ISBN:1590590732

In this chapter, we use the SQL Server Apress © 2003 (928 pages) database as the data source to test the code samples. Hence, we use the System.Data.SqlClient (or justcoverage SqlClient) name-space most of the time. Before going any This text provides extensive of ADO.NET technology further, let's explore the SqlClient namespace and see what it has to offer. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

Table 4-1 describes namespaces the SqlClient and classes, namespace and how classes. to integrate both with ADO.NET.

Table 4-1: Sql Data Provider Classes Table of Contents CLASS

DESCRIPTION


SqlClientPermission Introduction Chapter 1

- ADO.NET Basics

Makes sure the user who is accessing the data has permission to access a data source.

Chapter 2 - Data Components in Visual StudioSets .NETpermission attributes. SqlClientPermissionAttribute Chapter 3 - ADO.NET in Disconnected Environments

SqlCommand Represents a SQL statement or stored procedure. - ADO.NET in Connected Environments Data can be returned in a DataReader by calling its Chapter 5 - Handling ADO.NET Events ExecuteReader method. Chapter 4 Chapter 6


Chapter SqlCommandBuilder 7 - Data Binding and Windows Forms Provides Data-Bound Controls a mechanism to generate automatic Chapter 8 - Constraints and Data Relations commands for a table. Chapter 9


SqlConnection

Represents a Connection object. This is first class you need to use to connect to a data source.


SqlDataAdapter Set ofProviders commands that provides a link between Chapter 12 - Oracle, SQLXML, and Other .NET Data SqlConnection and DataSet. Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using SqlDataReader Reads dataASP.NET in a forward-only direction through Chapter 15 - Using ADO.NET in Xml Web Services SqlCommand. Chapter 16 - ASP.NET Server Controls and Data Binding

SqlError Collects error and warnings returned by the data Chapter 17 - Building Real-World Web Applications source.


Chapter 19 - Mapped Objects: Performance Considerations andgenerated Data Binding SqlErrorCollection Collects errors by Sql data providers. Chapter 20 - COM Interoperability and ADO.NET

SqlException


Exception handling class designed for Sql data sources.


SqlInfoMessageEventArgs Appendix A - Relational Databases: Some BasicProvides Conceptsdata for the InfoMessage event. Appendix B - Commonly Used SQL Statements

SqlParameter

This class represents a parameter used in SqlCommand.

Appendix C - ADO.NET Frequently Asked Questions Index ListSqlParameterCollection of Figures

A collection of parameters.

ListSqlRowUpdateEventArgs of Tables

Provides data for the RowUpdated event.

List of Listings ListSqlRowUpdatingEventArgs of Sidebars

SqlTransaction

Provides data from the RowUpdating event. A transaction that can be processed at a data source.

Like the Sql data provider, the OleDb, ODBC, and other data providers implement the same class hierarchy model. Programmatically, the only difference is the prefix for each data provider namespace and the connection string. Internally, each data provider uses a different native data access technology to access the data source. For example, the OleDb provider classes begin with OleDb, the Sql Server provider namespace classes start with Sql, and the ODBC provider classes begin with Odbc . The System.Data classes have no provider-specific prefix, of course, because the classes defined in the System.Data and System.Data.Common namespaces are used in memory and are shared by all the providers.

The way ADO.NET works is that once you've connected to a database and dumped the data into the inApplied ADO.NET: Building Data-Driven Solutions memory object (known as the DataSet), you can disconnect from the database and manipulate the data ISBN:1590590732 Chand and David Talbot until you're readyby to Mahesh write it back to the database. The data provider classes serve as a bridge for moving Apress © 2003 (928 pages) data back and forth between memory and the database. In the next section we discuss how to initially This text provides technology connect to a database using theseextensive providerscoverage and howoftoADO.NET implement the data provider classes to allow data including ADO.NET internals, namespaces, classes, and to use this efficient bridge. interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with

In the sections that follow we describe how to connect to various databases with the data providers. Then ADO.NET. we show you how to use the data provider classes to execute queries and stored procedures. Also, you'll learn how these powerful classes work together and how the data providers differ in certain capabilities. Table ofalso Contents You'll learn how to do transaction locking, batch transactions, and transaction rollbacks. Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building to Data-Driven The Connection: Connecting a Data Solutions Source by Mahesh Chand and David Talbot

ISBN:1590590732

As you saw in Figure 4-1, the first object that interacts with a data source is the Connection object. You Apress © 2003 (928 pages) can bypass a Connection object by using acoverage DataAdapter directly, but in that case a DataAdapter This text provides extensive of ADO.NET technology uses the Connection internally. The Connection class has a different name depending upon the data including ADO.NET internals, namespaces, classes, and interfaces, and takes comprehensive XMLOleDbConnection, SqlConnection, provider. The Connection class for aOleDb, Sql, and look Odbcatare namespaces and classes, and how to integrate both with respectively. ADO.NET.

Creating a Connection

Table of Contents

Applied TheSqlConnection ADO.NET—Building class Data-Driven provides Solutions two forms of constructors. The first doesn't take any parameters, Introduction and the second takes a parameter of a connection string that points to the database to which you want to

attach. 1The connection string contains the server name, database name, user ID, password, and more. Chapter - ADO.NET Basics Chapter 2


Chapter 3


Listing 4-1 creates SqlConnection objects using both constructors.

Chapter - ADO.NET Connected Environments Listing44-1: CreatinginSqlConnection Objects Chapter 5


Chapter 6


Dim connString As String = "user id=sa;password=password;" & _ - Data Binding and Windows Forms Data-Bound Controls "initial catalog=northwind;data source=Northwind;Connect Timeout=30" Chapter 8 - Constraints and Data Relations Dim conn1 As SqlConnection = New SqlConnection(connString) Chapter 9 - ADO.NET Exception Handling Dim conn2 As SqlConnection = New SqlConnection() Chapter 10 - Working with the ODBC .NET Data Provider conn2.ConnectionString = connString Chapter 7

Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

After creating a connection, you Web call its Open method, when you're done with the connection, you call Chapter 14 - Developing Database Applications using and ASP.NET theClose Chapter 15 -method. Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Understanding the Connection Properties and Methods


TheConnection (SqlConnection in this case) and hasData a connection Chapter 19 - Mappedclass Objects: Performance Considerations Binding string that contains a server and a database The connection will vary depending upon the provider used. The connection Chapter 20 - name. COM Interoperability andstring ADO.NET string will contain a group of property-value pairs to describe how to connect to a database. For Chapter 21 typically - Messaging theOleDbConnection class, you have properties such as Provider and DataSource. For the Chapter 22 - SQL Server and ADO.NET: Notes on Performance

SqlConnection class, you have the server name, initial catalog, user ID, and password. Table 4-2 describes the Connection class properties. (Based on the data provider, some of these properties may Appendix B - Commonly Used SQL Statements not be applicable.) Appendix A - Relational Databases: Some Basic Concepts Appendix C - ADO.NET Frequently Asked Questions Index

Table 4-2: Connection Object Properties



PROPERTY

DESCRIPTION Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot The connection string. Apress © 2003 (928 pages)

ConnectionString

ISBN:1590590732

ConnectionTimeOut This text provides Waiting extensive time while coverage establishing of ADO.NET a connection. technology including ADO.NET internals, namespaces, classes, and Name of athe current database. interfaces, and takes comprehensive look at XML namespaces and classes, and how to integrate both with DataSource ADO.NET. Filename of the data source.

DataBase

Provider Table of Contents

Name of the OLE DB provider. This property is not available for the Sql and ODBC data providers.

Applied ADO.NET—Building Data-Driven Solutions State Current state of the connection of type ConnectionState. Introduction

PacketSize Chapter 1 - ADO.NET Basics Size of network packets. This is only available to Sql data providers. Chapter 2 - Data ComponentsSQL in Visual Studio .NET This is only available to Sql data providers. ServerVersion Server version. Chapter 3 - ADO.NET in Disconnected Environments

WorkStationId Database client ID. This is only available to Sql data providers. - ADO.NET in Connected Environments

Chapter 4 Chapter 5


A typical connection for SQL Server may also contain the security type, the workstation ID, and even the - Integrating XML with ADO.NET network packet size. The following code is a connection string for a SQL Server called MCB:

Chapter 6 Chapter 7


Chapter 8


connectionString = Chapter 9 - ADO.NET Exception Handling "data source=MCB;initial catalog=Northwind;" + "integrated security=SSPI;persist security info=False;" Chapter 11 - Stored Procedures and Views + "workstation id=MCB;packet size=4096"; Chapter 10 - Working with the ODBC .NET Data Provider


Chapter 14 - Developing Database Web states Applications using ASP.NET TheConnection can have different such as open, closed, connecting, and so on. The Chapter 15 - Using ADO.NET in Xml defines Web Services ConnectionType enumeration the members of the ConnectionState.Table 4-3 describes its Chapter 16 - ASP.NET Server Controls and Data Binding members. Chapter 17 - Building Real-World Web Applications

Table 4-3: ConnectionType Enumeration Members Chapter 18 - The Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

MEMBER

DESCRIPTION

Chapter 20 - COM Interoperability and ADO.NET Chapter Broken 21 - Messaging Connection is broken after it was opened. This may be caused by network Chapter 22 - SQL Server failure. and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Closed

Connection is closed.


Connecting Opening a new connection. Appendix C - ADO.NET Frequently Asked Questions Index

Executing

List of Figures

The connection is executing a command.

ListFetching of Tables

Retrieving data from a data source.

ListOpen of Listings

Connection is open and ready to use.

List of Sidebars

Table 4-4 describes the Connection class methods. You'll see some of these methods throughout this chapter. The purpose of this table is to give you an idea of available methods. Table 4-4: The Connection Class Members

METHOD

DESCRIPTION Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Begins a database transaction. Apress © 2003 (928 pages)

BeginTransaction

ISBN:1590590732

ChangeDatabase This text provides Changes extensive databases coverage for an of open ADO.NET connection. technology including ADO.NET internals, namespaces, classes, and Closes open connection. interfaces, and takesan a comprehensive look at XML namespaces and classes, and how to integrate both with CreateCommand ADO.NET. Creates and returns a Command objects depends on the data provider.

Close

For example, OleDbConnection returns OleDbCommand, and SqlConnection returns SqlCommand. Table of Contents

OpenADO.NET—Building Data-Driven Opens aSolutions new connection. Applied Introduction ReleaseObjectPool Chapter 1

Represents that the connection pooling can be cleared when the

Chapter 2

- ADO.NET Basics provider is released. This is only available for OleDb data providers. - Data Components in Visual Studio .NET

Chapter 3


Chapter 4

- ADO.NET in Connected Environments Opening and Closing a Connection - Handling ADO.NET Events

Chapter 5

Chapter XML with As you 6can- Integrating see from Listing 4-1,ADO.NET the code creates two Connection objects: conn1 and conn2. It creates Chapter 7 Data Binding and Windows Forms Data-Bound Controls conn1 with no connection string. If you create a Connection object with no connection string, you must Chapter set its ConnectionString 8 - Constraints and Data property Relations before you call the Open method of the Connection object. The

code creates the conn2 objectHandling with a connection string as an argument. As you can see from the Chapter 9 - ADO.NET Exception connection it consists of a provider name and data source. Chapter 10 - string, Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

Note All the providers construct their connections in the same way. The thing that makes the connection construction different from other different providers is the ConnectionString. For Chapter 13 - Developing a Custom Data Provider example, the SqlClient namespace doesn't need to specify a provider string because Sql Chapter 14 - Developing Database Web Applications using ASP.NET Server is always the database when using this class. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


Chapter 16 - ASP.NET Server Controls and Data After creating a Connection object, you callBinding its Open method to open a connection. The Open method Chapter 17 Building Real-World Web Applications doesn't take any arguments. The following code opens a connection: Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding conn.Open() Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

When you're done with and the connection, you on callPerformance its Close method to release the connection. The Close Chapter 22 - SQL Server ADO.NET: Notes method Aalso doesn't take any arguments. The following code closes a connection: Appendix - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

conn.Close() Appendix C - ADO.NET Frequently Asked Questions Index List of Figures

Listing 4-2 opens a connection with the Access 2000 Northwind database that resides in the C:\ directory. As you can see, you check the connection state to see if the connection is already opened (which is List of Listings impossible in this code) or closed. List of Tables

List of Sidebars

Listing 4-2: Connecting to an OleDb Database and Reading the OleDbConnection Properties ' Create a Connection Object Dim ConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _ "Data Source=c:\\Northwind.mdb" Dim conn As OleDbConnection = New OleDbConnection(ConnectionString) ' Open the connection If conn.State ConnectionState.Open Then conn.Open() MessageBox.Show("Connection state: " + conn.State.ToString()) End If

' Show the connection properties Applied ADO.NET: Building Data-Driven MessageBox.Show("Connection String :" + Solutions conn.ConnectionString & _ ISBN:1590590732 by Mahesh Chand and David Talbot ", DataSource :" + conn.DataSource.ToString() & _ Apress © 2003 (928 pages) ", Provider :" + conn.Provider.ToString() & _ This"," text provides extensive coverage of ADO.NET technology + conn.ServerVersion.ToString() & _ including ADO.NET internals, namespaces, classes, and "," + conn.ConnectionTimeout.ToString()) interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ' Close the connection ADO.NET.

If conn.State = ConnectionState.Open Then conn.Close() Table of MessageBox.Show("Connection Contents state: " + conn.State.ToString()) Applied ADO.NET—Building Data-Driven Solutions End If Introduction ' Dispose the connection Chapter - ADO.NET If1 (Not conn Basics Is Nothing) Then Chapter conn.Dispose() 2 - Data Components in Visual Studio .NET End Chapter 3 If - ADO.NET in Disconnected Environments Chapter 4


Chapter 5


Chapter 6


Caution To utilize connection resources properly, it's always recommended to close open - Data Binding and Windows Forms Data-Bound Controls connections and dispose of connections explicitly if you don't intend to use them again. If you Chapter 8 - Constraints and Data Relations don't dispose of connections, the garbage collector will take care of it; however, the garbage Chapter 9 - ADO.NET Exception Handling collector waits for a certain interval of time. To force the garbage collector to dispose of Chapter 10 - Working with the ODBC .NET Data Provider connections, you call the Dispose method of the SqlConnection. The call to the Chapter 11 - Stored Procedures and Views Dispose method destroys the connection resource immediately. Chapter 7


Chapter 13also - Developing a Custom Provider You can use the OleDb dataData provider to connect to SQL Server or other databases if you have an Chapter 14data - Developing Databasefor Web Applications ASP.NET OLE DB provider installed that database.using Listing 4-3 shows the connection for a SQL Server using Chapter the OleDb 15 -data Using provider. ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Listing17 4-3: Connecting to a SQL Server Using the OleDb Data Provider Chapter - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

' Create a Connection Object Considerations and Data Binding Chapter 19 - Mapped Objects: Performance As String = "Provider=SQLOLEDB.1;" & _ ChapterDim 20 -ConnectionString COM Interoperability and ADO.NET "Integrated Security=SSPI;" & _ Chapter 21 - Messaging "Persist Info=false;" & _ Chapter 22 - SQL Server andSecurity ADO.NET: Notes on Performance "Initial Catalog=Northwind;" Appendix A - Relational Databases: Some Basic Concepts & _ "Data Source=MCB;" Dim conn As OleDbConnection = New OleDbConnection(ConnectionString) Appendix C - ADO.NET Frequently Asked Questions ' Open the connection Index If conn.State ConnectionState.Open Then List of Figures conn.Open() List of Tables MessageBox.Show("Connection state: " + conn.State.ToString()) List of Listings End If Appendix B - Commonly Used SQL Statements

List of Sidebars

Now you'll connect to a SQL Server database using the Sql data provider. For this example, you'll use the SQL Server 2000 Northwind database. Listing 4-4 shows the connection with the SQL Server database. As you can see, the code first constructs a connection string with the SQL Server name MCB and the database name Northwind. It uses Windows security in this connection, but depending on your SQL Server setup you could alternatively use a SQL Server login and password. After constructing a connection string, it calls the Open method to open the connection. After that it reads the connection properties and displays them in a message box. In the end, it calls the Close method to close the connection and the Dispose method to get rid of the connection resources.

Listing 4-4: Connecting to a SQL Server and Reading the SqlConnection Properties Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

' Create a Connection Object Apress © 2003 (928 pages) Dim ConnectionString As String = "Integrated Security=SSPI;" & _ This text provides extensive coverage of ADO.NET technology "Initial Catalog=Northwind;Data Source=MCB;" including ADO.NET internals, namespaces, classes, and Dim conn Asinterfaces, SqlConnection New SqlConnection(ConnectionString) and takes a =comprehensive look at XML and classes, and how to integrate both with ' Open the namespaces connection ADO.NET. If conn.State ConnectionState.Open Then conn.Open() MessageBox.Show("Connection state: " + conn.State.ToString()) Table of Contents End If Applied ADO.NET—Building Data-Driven Solutions ' Show the connection properties Introduction MessageBox.Show("Connection String :" + conn.ConnectionString & _ Chapter 1 - ADO.NET Basics ", Workstation Id:" + conn.WorkstationId.ToString() & _ Chapter 2 - Data Components in Visual Studio .NET ", Packet Size :" + conn.PacketSize.ToString() & _ Chapter 3 - ADO.NET in Disconnected Environments ", Server Version " + conn.ServerVersion.ToString() & _ Chapter 4 - ADO.NET Connected Environments ",in DataSource :" + conn.DataSource.ToString() & _ Chapter 5 - Handling", ADO.NET Events Server Version:" + conn.ServerVersion.ToString() & _ Chapter 6 - Integrating with ADO.NET ", XML Connection Time Out:" + conn.ConnectionTimeout.ToString()) Chapter 7


Chapter 8 - Constraints and Data Relations ' Close the connection Chapter If conn.State 9 - ADO.NET Exception = ConnectionState.Open Handling Then Chapterconn.Close() 10 - Working with the ODBC .NET Data Provider

state: " + conn.State.ToString()) ChapterMessageBox.Show("Connection 11 - Stored Procedures and Views End12If- Oracle, SQLXML, and Other .NET Data Providers Chapter ' Dispose the connection Chapter 13 - Developing a Custom Data Provider If (Not conn IsDatabase Nothing) Then Chapter 14 - Developing Web Applications using ASP.NET conn.Dispose() End If

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19even - Mapped Objects: Considerations and Data Binding You can pass a user IDPerformance and password in a connection string. For example, the following connection Chapter 20 COM Interoperability and ADO.NET string uses a user ID and password: Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Dim ConnectionString As String = "user id=sa;password=pass;" & _

Appendix A - Relational"Initial Databases: Some Basic Concepts Catalog=Northwind;Data Source=MCB;" Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index

As you can see, we used MCB as the data source name. You can use localhost as your local List ofNote Figures server. List of Tables List of Listings

Understanding Connection Pooling

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Connection pooling is a mechanism to utilize and share connection resources already available in a connection pool. In general, if an application needs a connection, it creates a new connection. There's a whole process of establishing a new connection. When the application is done using a connection, it closes the connection. Connection pooling plays a vital role in a three-tier development. For example, in a three-tier development, say you're using a Web server. The opening and closing of a connection consumes time and server resources in this scenario. Now say the application executes only a SELECT statement, which returns only a few records from the database. It may be possible that establishing a connection with the server may take more time than executing the query. This situation gets worse when there are hundreds of users accessing the same server. Another scenario is that a user logs into a server and then stays connected, never logging out. So, having a connection open until a user logs out is not a

feasible solution.


ISBN:1590590732 by Mahesh Chandhelp and in David Talbot So how does connection pooling this scenario? In the .NET Framework, when an application Apress 2003 (928 pages) closes a connection, the©connection goes to a pool of available connections and stays active for a certain interval of time even you closeextensive the connection. a user technology connects, the provider compares the Thisafter text provides coverageWhen of ADO.NET ADO.NET internals, classes, connection stringincluding to the connection strings in namespaces, the pool. If the string and matches, then a connection is returned interfaces, and takes comprehensive look at XML from the pool instead of creating and aopening a new connection.


The connection pooling mechanism works differently for different data providers. The Connection class defines members that allow you to pool connection resources manually. Table of Contents

OLE DB provides automatic connection pooling (also known as sessionpooling), which is handled by OLE DB core components through its providers.


Chapter 1 you - ADO.NET Basicsof the OLE DB Services parameter, which includes connection pooling as In ADO, set the value Chapter well. This 2 is - Data an ADO Components connection in Visual string Studio passed .NET to the Open method of an OLEDBConnection: Chapter 3


Chapter 4 - ADO.NET in Connected Environments Dim conn As OLEDBConnection = Nothing Chapter 5 - Handling ADO.NET Events Conn.Open("DSN=LocalServer;UID=sa;PWD=;OLE DB Services=-1") Chapter 6 - Integrating XML with ADO.NET Chapter 7


Table 4-5 theand values the OLE DB Services parameter. Chapter 8 -describes Constraints Datafor Relations Chapter 9


Table 4-5: OLEwith DB the Services Settings Chapter 10 - The Working ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views SERVICES ENABLED

VALUE


All services (default) a Custom Data Provider Chapter 13 - Developing

"OLE DB Services = –1;"

Chapter 14 - Developing Database Web Applications using ASP.NET "OLE DB Services = –2;" All services except pooling Chapter 15 - Using ADO.NET in Xml Web Services

All services except Server poolingControls and auto enlistment Chapter 16 - ASP.NET and Data Binding


Chapter 17 - Building Web Applications All services exceptReal-World client cursor



All services except client cursor and pooling


Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET No services

"OLE DB Services = 0;"

Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

For example, the following string Some disables theConcepts connection pooling: Appendix A - Relational Databases: Basic Appendix B - Commonly Used SQL Statements

Dim connString String = "Provider = SQLOLEDB OLE DB Services = -2;" & _ Appendix C - ADO.NET As Frequently Asked Questions "Data Source = MCB; Integrated Security = SSPI " Index List of Figures List of Tables

ADO .NET manages connection pooling automatically when you call the Close or Dispose method of a Connection object. Once a pool is created, you can add connections to this pool until the pool reaches List of Sidebars its maximum size. You can define the maximum size of a connection pool using the connection string. If a pool reaches its maximum size, the next added connection will join a queue and wait until the pool releases an existing connection. List of Listings

You create a pool when you call the Open method of a connection based on the connection string. If you're using the same database for two Connection objects, but the connection string is different (including spaces and single characters), each connection will be added to a different pool. For example, Listing 4-5 creates two connections: conn1 and conn2. The ConnectionString1 and ConnectionString2 connection strings are different for both connections. Because these connections have different connection strings, they'll be added to two different pools. Listing 4-5: Creating Two Connections with Different Strings

' Create a Connection Object Applied ADO.NET: Building Data-Driven Solutions Dim ConnectionString1 As String "IntegratedISBN:1590590732 Security=SSPI;" & _ by Mahesh Chand and David = Talbot "Initial Catalog=Northwind;" & _ Apress © 2003 (928 pages) "Data Source=MCB;" This text provides extensive coverage of ADO.NET technology Dim conn1 As including SqlConnection = New namespaces, SqlConnection(ConnectionString1) ADO.NET internals, classes, and ' Create a Connection interfaces, andObject takes a comprehensive look at XML namespaces and and=how to integrate both with Dim ConnectionString2 As classes, String "Integrated Security=SSPI;" & _ ADO.NET. "Initial Catalog=Pubs;" & _ "Data Source=MCB;" Dim conn2 As SqlConnection = New SqlConnection(ConnectionString2) Table of Contents ' Open connections Applied ADO.NET—Building Data-Driven Solutions conn1.Open() Introduction conn2.Open() Chapter 1 - ADO.NET Basics MessageBox.Show("Connection1 " + conn1.State.ToString()) Chapter 2 - Data Components in Visual Studio .NET MessageBox.Show("Connection2 " + conn2.State.ToString()) Chapter 3 - ADO.NET in Disconnected Environments ' some code Chapter 4 - ADO.NET in Connected Environments conn1.Close() Chapter 5 - Handling ADO.NET Events conn2.Close() Chapter 6 - Integrating XML with ADO.NET" + conn1.State.ToString()) MessageBox.Show("Connection1 Chapter 7 - Data Binding and Windows Forms Controls MessageBox.Show("Connection2 " + Data-Bound conn2.State.ToString()) Chapter 8


Chapter 9



Caution You must alwaysand callViews the Close or Dispose method of Connection to close the Chapter 11 - Stored Procedures connection. Connections that are not explicitly closed are not added or returned to the pool. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

Even though the .NET Framework automatically manages connection pooling, you can customize the connection pooling properties programmatically by passing them in a connection string or by setting them Chapter 15 - Using ADO.NET in Xml Web Services using the Connection properties. A typical connection string with connection pooling parameters looks Chapter 16 - ASP.NET Server Controls and Data Binding like the following: Chapter 14 - Developing Database Web Applications using ASP.NET


Dim ConnectionString As String = "user id=sa;password=pass;" & _ "Initial Catalog=Northwind;Data Source=MCB;" & _ Chapter 20 - COM Interoperability and ADO.NET "Pooling='true';Connection Reset='false';" & _ Chapter"Connection 21 - Messaging Lifetime=5;Min Pool Size=3;Max Pool Size=20;" Chapter 19 - Mapped Objects: Performance Considerations and Data Binding


Some ofBthe pooling settings areStatements in the form of key-value pairs (see Table 4-6). Appendix - Commonly Used SQL Appendix C - ADO.NET Frequently Asked Questions

Table 4-6: Connection Pooling Settings Index List of Figures List of Tables List of Listings List of Sidebars

KEY

DESCRIPTION Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

Connection Connection creation time is compared with the current time, and if time span Apress © 2003 (928 pages) Lifetime exceeds the Connection Lifetime value, the object pooler destroys the This text provides extensive coverage of ADO.NET technology connection. The default value is 0, which will give a connection the maximum including ADO.NET internals, namespaces, classes, and timeout. interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with

Connection ADO.NET. Determines whether a connection is reset after it was removed from the Reset pool. The default value is True. Maximum number of connection allowed in the pool. The default value is 100. Applied ADO.NET—Building Data-Driven Solutions Introduction Min Pool Minimum number of connections allowed in the pool. The default value is 0. Chapter Size1 - ADO.NET Basics Max Pool Size

Table of Contents

Chapter 2


Chapter 3


Chapter 4


Pooling

WhenTrue (the default), the connection is drawn from the pool or created if necessary.

Chapter 5

- Handling ADO.NET Events TheOleDbConnection class provides a ReleaseObjectPool method you can use to free resources - Integrating XML with ADO.NET reserved for a connection. You call this method when this connection won't be used again. To call Chapter 7 - Data Binding and Forms Data-Bound ReleaseObjectPool, first Windows you call the Close method.Controls Listing 4-6 shows how to use Chapter 8 - Constraints and Data Relations ReleaseObjectPool. Chapter 6

Chapter 9


Listing10 4-6: Callingwith ReleaseObjectPool Chapter - Working the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle,and SQLXML, Other .NET Data Providers ' Connection SQL and strings Chapter 13 - Developing a Custom Provider Dim ConnectionString As Data String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _ Chapter - Developing Database Web Applications using ASP.NET "Data14Source=c:\\Northwind.mdb" Chapter Dim SQL 15 -As Using String ADO.NET = in"SELECT Xml Web Services OrderID, Customer, CustomerID FROM Orders"

' Create connection objectand Data Binding Chapter 16 - ASP.NET Server Controls Dim conn As OleDbConnection = New OleDbConnection(ConnectionString) Chapter 17 - Building Real-World Web Applications conn.Open() Chapter 18 - Object-Relational Mapping in .NET ' do something Chapter 19 - Mapped Objects: Performance Considerations and Data Binding conn.Close() Chapter 20 - COM Interoperability and ADO.NET OleDbConnection.ReleaseObjectPool() ' Dispose the connection Chapter 22 - SQL Server and ADO.NET: Notes on Performance If (Not conn Is Nothing) Then Appendix A - Relational Databases: Some Basic Concepts conn.Dispose() Appendix B - Commonly Used SQL Statements End If Chapter 21 - Messaging

Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables

Using the CreateCommand and ChangeDatabase Methods

List of Listings

List of Sidebars

TheSqlConnection class provides two more useful methods: the CreateCommand and ChangeDatabase methods. The CreateCommand method creates a SqlCommand object, which will be associated with the Connection object. In general, when you create a SqlCommand object, you need to pass a SqlConnection argument to connect to a connection, but if you use the CreateCommand method of SqlConnection, you don't need to do so. The following code creates a SqlCommand using the CreateCommand method of an already existing SqlConnection object: Dim cmd As SqlCommand = conn.CreateCommand() cmd.CommandText = "SELECT * FROM Customers" ' Do something with the command


We discuss SqlCommand more and detail in the following section. ISBN:1590590732 by MaheshinChand David Talbot Apress © 2003 (928 pages)

TheChangeDatabase method of the SqlConnection object is a relief to developers who frequently This text provides extensive coverage of ADO.NET technology have to change the database to which they're connected. This feature was missing in previous including ADO.NET internals, namespaces, classes, and technologies, andinterfaces, the only way of athis problem waslook to disconnect the connection and then reconnect and out takes comprehensive at XML to the new database. The ChangeDatabase method does theboth same namespaces and classes, and how to integrate withthing, but it does so internally so that ADO.NET. developers can continue using the same SqlConnection object. The following code opens a connection to the Northwind database and later changes the database source using the ChangeDatabase: Table of Contents

' Create a Connection Object Applied ADO.NET—Building Data-Driven Solutions Dim ConnectionString As String = "Integrated Security=SSPI;" & _ "Initial Catalog=Northwind;Data Source=MCB;" Chapter 1 - ADO.NET Basics Dim conn As SqlConnection = New SqlConnection(ConnectionString) Chapter 2 - Data Components in Visual Studio .NET ' Open the connection Chapter 3 - ADO.NET in Disconnected Environments conn.Open() Chapter 4 - ADO.NET in Connected Environments conn.ChangeDatabase("pubs") Chapter'5 Do- Handling ADO.NET Events something with the command ChapterMessageBox.Show(conn.Database.ToString()) 6 - Integrating XML with ADO.NET Chapter'7 Close - Data the Binding and Windows and Formscall Data-Bound Controls connection Dispose Chapter 8 conn.Close() - Constraints and Data Relations Chapter 9 conn.Dispose() - ADO.NET Exception Handling Introduction


AppliedExecuting ADO.NET: Building Data-Driven Solutions The Command: SQL Statements by Mahesh Chand and David Talbot

ISBN:1590590732

TheCommand object allows you topages) directly execute SQL statements such as INSERT,SELECT,UPDATE, Apress © 2003 (928 andDELETE against a data source for reading, writing,ofand updating a database. You can also use the This text provides extensive coverage ADO.NET technology Command object including to execute stored procedures. The SqlCommand, OleDbCommand, and OdbcCommand ADO.NET internals, namespaces, classes, and and takes a comprehensive look and at XML classes representinterfaces, the Command objects in the Sql, OleDb, ODBC data providers, respectively. namespaces and classes, and how to integrate both with ADO.NET. Table 4-7 describes some of the more important properties of the Command class for the Sql data provider. The CommandText listed in this table can contain either a SQL statement or a stored procedure name. The CommandType determines which one of these forms the CommandText takes.

Table of Contents


Table 4-7: The Command Properties

Introduction

Chapter 1 - ADO.NET Basics DESCRIPTION PROPERTY Chapter 2 - Data Components in Visual Studio .NET

CommandText

Could be a SQL statement, a stored procedure, or a database table name depending on the CommandType

Chapter 3


Chapter 4


Chapter CommandTimeout 5 - Handling ADO.NETWait Events time before terminating the execute command Chapter 6 - Integrating XML with ADO.NET

CommandType

Chapter 7

An enumeration of values Text,StoredProcedure, or TableDirect


Chapter 8

- Constraints and Data Relations Connection AConnection representing the ActiveConnection Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

DesignTimeVisible

Indicates whether the command should be visible at design-time


Parameters A collection of parameters (SqlParameterCollection) Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Transaction

A transaction


UpdateRowSource how command results are applied to a DataRow when Chapter 15 - Using ADO.NET inRepresents Xml Web Services used byand theData Update method Chapter 16 - ASP.NET Server Controls Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Listing 4-7 creates a SqlCommand object, sets its properties, and then reads back its properties to display

Chapter 19 - Mapped Performance Considerations and Data Bindingthe related sections of this chapter. them. You'll see theObjects: rest of the properties—such as Transaction—in Chapter 20 - COM Interoperability and ADO.NET Chapter Listing21 4-7: - Messaging Setting and Getting SqlCommand Properties Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Some Basic Concepts ' Connection andDatabases: SQL strings Appendix B -ConnectionString Commonly Used SQL Statements Dim As String = "Integrated Security=SSPI;" & _ Appendix C - ADO.NET FrequentlyCatalog=Northwind;Data Asked Questions "Initial Source=MCB;" Index Dim SQL As String = "SELECT * FROM Orders" List of Figures ' Create connection object List of Tables Dim conn As SqlConnection = New SqlConnection(ConnectionString)

' Create command object List of Listings Dim cmd As SqlCommand = New SqlCommand() List of Sidebars cmd.Connection = conn cmd.CommandText = SQL cmd.CommandTimeout = 30 cmd.CommandType = CommandType.Text ' Open connection conn.Open() ' Read Command properties Dim str As String str = "Connection String: " + cmd.Connection.ConnectionString.ToString() str = str + " , SQL Statement :" + cmd.CommandText str = str + " , Timeout :" + cmd.CommandTimeout.ToString()

str = str + " , CommandTyoe:" + cmd.CommandType.ToString() Applied ADO.NET: Building Data-Driven Solutions MessageBox.Show(str) ISBN:1590590732 by Mahesh Chand and David Talbot ' close connection Apress © 2003 (928 pages) conn.Close() 'Dispose This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and conn.Dispose() interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Creating a Command Object

Table of Contents


There are a number of ways to construct a Command object. You can create a Command and set its connection and SQL string, or you can create a Command by passing the connection string and SQL string Chapter 1 - ADO.NET Basics as parameters of the Command constructor. Introduction Chapter 2


Chapter 3 - ADO.NET in Disconnected Environments The following examples show you three different ways to create a Command object. This code constructs a Chapter 4 - and ADO.NET in string: Connected Environments connection a SQL Chapter 5


Chapter 6 - Integrating ADO.NET ' Connection and XML SQLwith strings Chapter 7 - Data Binding and Windows Forms= Data-Bound Controls Dim ConnectionString As String "Integrated Security=SSPI;" & _ Chapter 8 - Constraints Data Relations "Initialand Catalog=Northwind;Data Source=MCB;" Chapter ' Create 9 - ADO.NET connection Exception object Handling

Dim conn As SqlConnection = New Chapter 10 - Working with the ODBC .NET DataSqlConnection(ConnectionString) Provider Dim SQL String = "SELECT Chapter 11 -As Stored Procedures and Views* FROM Orders" Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

Now create a SqlCommand object using a constructor with no arguments. Later you set SqlCommand's Connection and CommandText properties to connect to a Connection and set the SQL statement, Chapter 15 - Using ADO.NET in Xml Web Services which this command will be executing: Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

' Create command object Dim cmd1 As SqlCommand = New SqlCommand() Chapter 19 - Mapped Objects: Performance Considerations and Data Binding cmd1.Connection = conn Chapter 20 - COM Interoperability and ADO.NET cmd1.CommandText = SQL Chapter 21 - Messaging cmd1.CommandTimeout = 30 Chapter 22 - SQL Server and ADO.NET: Notes on Performance cmd1.CommandType = CommandType.Text Chapter 18 - Object-Relational Mapping in .NET


In the second form, you create aAsked SqlCommand Appendix C - ADO.NET Frequently Questions object by directly passing a SQL query and the SqlConnection object as the first and second arguments: Index List of Figures

//ofCreate List Tables command object Dim cmd2 As SqlCommand = New SqlCommand(SQL, conn) List of Listings List of Sidebars

The third way of creating a Command object is to create a command by just passing a SQL query as the argument and setting its Connection property later: // Create command object Dim cmd3 As SqlCommand = New SqlCommand(SQL) cmd3.Connection = conn

Listing 4-8 shows you how to connect to the Northwind SQL Server database, read all the records from the Orders table, and output the first and second field's data to the console. The new things you'll notice in this code are ExecuteReader and SqlDataReader. A SqlDataReader is a DataReader class, and

ExecuteReader fills data from a data source to the DataReader based on the SQL query. (We discuss Applied ADO.NET: Building Data-Driven Solutions DataReader classes in the next section.) by Mahesh Chand and David Talbot

ISBN:1590590732

Apress © 2003 (928 to pages) Listing 4-8: Using SqlCommand Read Data from a Database This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and ' Connection interfaces, and SQLand strings takes a comprehensive look at XML Dim ConnectionString = how "Integrated Security=SSPI;" & _ namespaces As and String classes, and to integrate both with ADO.NET. "Initial Catalog=Northwind;Data Source=MCB;"

Dim SQL As String = "SELECT * FROM Orders" ' Create connection object Table of Contents Dim conn As SqlConnection = New SqlConnection(ConnectionString) Applied ADO.NET—Building Data-Driven Solutions ' Create command object Introduction Dim cmd As SqlCommand = New SqlCommand(SQL) Chapter 1 - ADO.NET = Basics cmd.Connection conn Chapter 2 connection - Data Components in Visual Studio .NET ' Open Chapter 3 - ADO.NET in Disconnected Environments conn.Open() Chapter 4 command's - ADO.NET in ExecuteReader Connected Environments ' Call Chapter 5 - Handling ADO.NET Events = cmd.ExecuteReader() Dim reader As SqlDataReader Chapter While6 reader.Read() - Integrating XML with ADO.NET If Not reader.IsDBNull(0) ThenData-Bound Controls Chapter 7 - Data Binding and Windows Forms Console.Write("OrderID:" + Chapter 8 - Constraints and Data Relations reader.GetInt32(0).ToString()) Console.Write(" ,") Handling Chapter 9 - ADO.NET Exception Console.WriteLine("Customer:" + reader.GetString(1).ToString()) Chapter 10 - Working with the ODBC .NET Data Provider End If Chapter 11 - Stored Procedures and Views End While Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers ' close reader and connection Chapter 13 - Developing a Custom Data Provider reader.Close() Chapter 14 - Developing Database Web Applications using ASP.NET conn.Close() Chapter 15 - Using ADO.NET in Xml Web Services 'Dispose Chapter 16 - ASP.NET Server Controls and Data Binding conn.Dispose() Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - of COM Interoperability ADO.NET The output Listing 4-8 will list and records from the Customers table to the console. Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Creating and Using OleDbCommand


Appendix Like the BSqlCommand - Commonly Used object, SQL you Statements create OleDb and ODBC Command objects by using the

OleDbCommand and Frequently OdbcCommand You can pass the same arguments as discussed previously. Appendix C - ADO.NET Askedclasses. Questions The only difference is the connection string. For example, Listing 4-9 uses OleDbCommand and Index OleDbConnection to connect to a SQL Server database. As you can see, the only changes are the List of Figures class prefixes and the connection string. Similarly, you can use the OdbcCommand object. List of Tables List of Listings

Listing 4-9: UsingOleCommand to Access an Access Database

List of Sidebars

' Connection and SQL strings Dim ConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _ "Data Source=c:\\Northwind.mdb" Dim SQL As String = "SELECT * FROM Orders" ' Create connection object Dim conn As OleDbConnection = New OleDbConnection(ConnectionString) ' Create command object Dim cmd As OleDbCommand = New OleDbCommand(SQL) cmd.Connection = conn ' Open connection

conn.Open() Applied ADO.NET: Building Data-Driven Solutions ' Call command's ExecuteReader ISBN:1590590732 by Mahesh Chand and David Talbot Dim reader As OleDbDataReader = cmd.ExecuteReader() Apress © 2003 (928 pages) While reader.Read() This text provides extensive+coverage of ADO.NET technology Console.Write("OrderID:" reader.GetInt32(0).ToString()) including ADO.NET internals, namespaces, classes, and Console.Write(" ,") interfaces, and takes a comprehensive look at XML Console.WriteLine("Customer:" namespaces and classes, and how + to reader.GetString(1).ToString()) integrate both with End WhileADO.NET. ' close reader and connection reader.Close() Table of Contents conn.Close() Applied ADO.NET—Building Data-Driven Solutions conn.Dispose() Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3

- ADO.NET in Disconnected Environments Using the CommandType Enumeration - ADO.NET in Connected Environments

Chapter 4

Chapter 5 - Handlingenumeration ADO.NET Events TheCommandType decides what type of object a command will be executed as. The Chapter 6 Integrating XML with CommandType enumeration canADO.NET have any of the three values defined in Table 4-8. Chapter 7


Chapter 8 - The Constraints and DataEnumeration Relations Table 4-8: CommandType Members Chapter 9


MEMBERS

DESCRIPTION

Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures Views StoredProcedure The and name of the stored procedure. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

TableDirect

TheCommandText property should be set to the table name, and all rows and columns in the table will be returned.


Chapter 14 - Developing Database Web Applications using ASP.NET Chapter Text15 - Using ADO.NETAinSQL Xmltext Webcommand. Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

As you can see from Table 4-8, you can call a stored procedure, use TableDirect, or execute a SQL command. We present these options individually in the following sections. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 18 - Object-Relational Mapping in .NET


Calling a Stored Procedure



Calling stored procedures using the Command object is similar to executing a SQL query. This section gives you a quick overview of how to execute stored procedures. (We cover stored procedures in more Appendix B - Commonly Used SQL Statements detail in Chapter 11.) Appendix A - Relational Databases: Some Basic Concepts Appendix C - ADO.NET Frequently Asked Questions

Index You need to set the CommandType property of a Command object before calling a stored procedure. By List of Figures default, the CommandType property is Text. If you want to call a stored procedure, you need to set the List CommandType of Tables to StoredProcedure and the CommandText to the stored procedure name. After that

youofcan call the ExecuteReader method or other methods. You can also pass parameters to the List Listings procedure by setting parameter values in the Command and then calling ExecuteReader on the List of Sidebars Command object. Alternatively, you can pass a procedure name as a string when creating a Command object.Listing 4-10 shows the settings of the CommandType and CommandText properties of SqlCommand. As you can see, it calls an existing SQL Server Northwind database stored procedure, Sales By Year. Listing 4-10: Calling a Stored Procedure Using SqlCommand ' Create a SqlCommand with stored procedure as string Dim cmd As SqlCommand = New SqlCommand("Sales By Year", conn) ' set Command's CommandType as StoredProcedure cmd.CommandType = CommandType.StoredProcedure


ISBN:1590590732

Note Executing stored procedures can be helpful in improving the performance of an application in Apress © 2003 (928 pages) multiuser and Web applications because a stored procedure executes on the server itself. This text provides extensive coverage of ADO.NET technology

includinginADO.NET internals, namespaces, classes, and The Northwind database SQL Server contains a few stored procedures. One is called Sales By Year interfaces, and takes a comprehensive look at XML (see Listing 4-11).namespaces and classes, and how to integrate both with ADO.NET.

Listing 4-11: The Sales By Year Stored Procedure in the Northwind Database Table of Contents

SELECT Orders.ShippedDate, Orders.OrderID, "Order Subtotals".Subtotal, DATENAME(yy,ShippedDate) AS Year Introduction FROM Orders INNER JOIN "Order Subtotals" ON Orders.OrderID = Chapter 1 -Subtotals".OrderID ADO.NET Basics "Order WHERE Orders.ShippedDate Chapter 2 - Data Components in Visual .NET BETWEEN @Beginning_Date ANDStudio @Ending_Date Applied ADO.NET—Building Data-Driven Solutions

Chapter 3


Chapter 4


Chapter 5

- Handling ADO.NET Events This stored procedure takes twoADO.NET parameters, Beginning_Date and Ending_Date. The procedure Chapter 6 - Integrating XML with

selects7all -ofData the Binding orders between theseForms two dates. It alsoControls performs a join with the Order Subtotals Chapter and Windows Data-Bound from the Subtotaland view, which calculates the subtotals of each. If you want to execute this stored Chapter 8 Order - Constraints Data Relations

procedure-inADO.NET ADO.NET, you just create a Command object of type StoredProcedure and then call the Exception Handling Command object's ExecuteReader method. You then cycle through the results in the reader that you're Chapter 10 - Working with the ODBC .NET Data Provider looking for from your stored procedure. Listing 4-12 executes a stored procedure that selects all the orders Chapter 11 - Stored Procedures and Views in July and displays their order IDs. Chapter 9


Chapter - Developing a Custom Data Provider Listing13 4-12: Executing and Reading the Results of a Stored Procedure Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Dim ConnectionString As String = "Integrated Security=SSPI;" & _ "Initial Catalog=Northwind;Data Source=MCB;" Chapter 17 - Building Real-World Web Applications Dim SQL As String = "SELECT * FROM Orders" Chapter'18 - Object-Relational Mapping in .NET Create connection object ChapterDim 19 -conn Mapped Performance Considerations and Data Binding AsObjects: SqlConnection = New SqlConnection(ConnectionString) Chapter'20 - COM Interoperability and with ADO.NET Create a SqlCommand stored procedure as string ChapterDim 21 -cmd Messaging As SqlCommand = New SqlCommand("Sales By Year", conn) Chaptercmd.Connection 22 - SQL Server and=ADO.NET: conn Notes on Performance Appendix ' Aset - Relational Command's Databases: CommandType Some Basic as Concepts StoredProcedure cmd.CommandType = CommandType.StoredProcedure Appendix B - Commonly Used SQL Statements ' C Create a SqlParameter and add a parameter Appendix - ADO.NET Frequently Asked Questions Dim parm1 As SqlParameter = cmd.Parameters.Add("@Beginning_Date", _ Index SqlDbType.DateTime, 20) List of Figures parm1.Value = "7/1/1996" List of Tables Dim parm2 As SqlParameter = cmd.Parameters.Add("@Ending_Date", _ List of Listings SqlDbType.DateTime, 20) List of Sidebars parm2.Value = "7/31/1996" ' Open connection conn.Open() ' Call ExecuteReader to execute the stored procedure Dim reader As SqlDataReader = cmd.ExecuteReader() Dim orderlist As String = "" ' Read data from the reader While reader.Read() Dim result As String = reader("OrderID").ToString() orderlist += result + " " End While ' close the connection and reader Chapter 16 - ASP.NET Server Controls and Data Binding

reader.Close() Applied ADO.NET: Building Data-Driven Solutions conn.Close() ISBN:1590590732 by Mahesh Chand and David Talbot conn.Dispose() Apress © 2003 (928 pages) ' Print data on the console This text provides extensive Console.WriteLine("Orders incoverage July")of ADO.NET technology including ADO.NET internals, namespaces, Console.WriteLine("===============") classes, and interfaces, and takes a comprehensive look at XML Console.WriteLine(orderlist) namespaces and classes, and how to integrate both with ADO.NET.

Table Contents If youofwanted to look at the subtotals along with the orders, you'd just add a DataReader index for Applied ADO.NET—Building Data-Driven Solutions dereferencing the subtotal and concatenate with the order ID. Listing 4-13 shows the new DataReader Introduction loop. Chapter 1

- ADO.NET Basics

Listing24-13: Adding the Subtotal Listing the Output of the Stored Procedure Results Chapter - Data Components in Visual Studioto .NET Chapter 3


Chapter While4 reader.Read() - ADO.NET in Connected Environments

Dim nextID As String = reader("OrderID").ToString() Chapter 5 - Handling ADO.NET Events Dim nextSubtotal Aswith String = reader("Subtotal").ToString() Chapter 6 - Integrating XML ADO.NET orderlist += nextID + ", " Forms + nextSubtotal + ", " Chapter 7 - Data Binding and Windows Data-Bound Controls End While Chapter 8 - Constraints and Data Relations Chapter 9



The result of replacing this line of code in Listing 4-13 gives output that returns order IDs and subtotals in the month of July in the Northwind database.



Using TableDirect


You can also use the TableDirect CommandType to read information directly from a table. You need

Chapter 17two - Building Real-World Web Applications to make changes in the example to execute a table by setting TableDirect. First, you need to set Chapter 18 - CommandText Object-Relationalproperty Mappingtointhe .NET Command's table name; second, you need to set the CommandType Chapter 19to- CommandType.TableDirect. Mapped Objects: Performance Considerations and Data Binding property Chapter 20 - COM Interoperability and ADO.NET

The following code reads the Customers table and sets the CommandType property to Chapter 21 - Messaging CommandType.TableDirect: Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

cmd.CommandText "Customers" Appendix B - Commonly = Used SQL Statements cmd.CommandType = CommandType.TableDirect Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables

Listing 4-14 reads information from the Customers table by setting the TableDirect method and displaying it on the console.

List of Listings

List of Sidebars

Listing 4-14: UsingTableDirect to Read a Table ' Create a Connection Object Dim ConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _ "Data Source=c:\\Northwind.mdb" Dim conn As OleDbConnection = New OleDbConnection(ConnectionString) Dim cmd As OleDbCommand = New OleDbCommand() cmd.Connection = conn cmd.CommandText = "Customers" cmd.CommandType = CommandType.TableDirect conn.Open()

Dim reader As OleDbDataReader = cmd.ExecuteReader() Applied ADO.NET: Building Data-Driven Console.WriteLine("Customer Id, ContactSolutions Name, Company Name") ISBN:1590590732 by Mahesh Chand and David Talbot Console.WriteLine("=======================================") Apress © 2003 (928 pages) While reader.Read() This text provides extensive coverage of ADO.NET technology Console.Write(reader("CustomerID").ToString()) including ADO.NET namespaces, classes, and Console.Write(", " +internals, reader("ContactName").ToString()) interfaces, and takes a comprehensive look at XML Console.WriteLine(", " +and reader("CompanyName").ToString()) namespaces and classes, how to integrate both with End WhileADO.NET. ' release objects reader.Close() Table of Contents conn.Close() Applied ADO.NET—Building Data-Driven Solutions conn.Dispose() Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3

- ADO.NET in Disconnected Environments Executing a Command - ADO.NET in Connected Environments

Chapter 4

Chapter 5 saw - Handling ADO.NET Eventsmethod, which reads data from a data source and fills the You just the ExecuteReader Chapter 6 Integrating XML with ADO.NET DataReader object depending on the data provider. Besides ExecuteReader, the Command object Chapter 7 Data Binding and methods. Windows Forms Controls defines three more execute TheseData-Bound methods are ExecuteNonQuery,ExecuteScalar, and Chapter ExecuteXmlReader 8 - Constraints .and TheData ExecuteReader Relations method produces a DataReader, which is the solution for

streaming through ADO.NET. (We discuss the DataReader in more details in "The DataReader: Chapter 9 -data ADO.NET Exception Handling Walking thewith Data.") Chapter 10through - Working the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

TheExecuteNonQuery method allows you to execute a SQL statement or a Command object with the CommandText property and a SQL statement without using a DataSet. This method doesn't take any Chapter 13 - Developing a Custom Data Provider parameters and returns the number of rows affected by the execute operation. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


Chapter 15 - Using in Xml Web Services For example, you ADO.NET could have an UPDATE, INSERT, or DELETE statement in your CommandText and then Chapter callExecuteNonQuery 16 - ASP.NET Server to execute Controls itand directly Data on Binding your database. Chapter 17 - Building Real-World Web Applications

Listing 4-15 shows how to insert a row into the Northwind database using the ExecuteNonQuery method. You can even use UPDATE and DELETE SQL queries to update and delete data from a database. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding (We use these statements in later examples.) In this example, you create an INSERT query and call Chapter 20 - COM Interoperability and ADO.NET ExecuteNonQuery. Chapter 18 - Object-Relational Mapping in .NET


Chapter - SQL ServerRecords and ADO.NET: Notes Using on Performance Listing22 4-15: Adding to a Table the INSERT SQL Statement Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

' Create a Connection Object Dim ConnectionString As String = "Integrated Security=SSPI;" & _ Index "Initial Catalog=Northwind;Data Source=MCB;" List of Figures Dim conn As SqlConnection = New SqlConnection(ConnectionString) Listopen of Tables an existing Connection to the Database and Create a List Listings Object with it: ' of Command List of Sidebars conn.Open() Dim cmd As SqlCommand = New SqlCommand("Customers", conn) ' Assign the SQL Insert statement we want to execute to the CommandText cmd.CommandText = "INSERT INTO Customers" & _ "(Address, City, CompanyName, ContactName, CustomerID)" & _ "VALUES ('111 Broad St.', 'NY', 'Xerox', 'Fred Biggles', 1400)" ' Call ExecuteNonQuery on the Command Object to execute insert Dim res As Integer res = cmd.ExecuteNonQuery() Console.WriteLine("Affected Rows :" + res.ToString()) ' release objects conn.Close() Appendix C - ADO.NET Frequently Asked Questions

conn.Dispose() Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

text provides extensive coverage of ADO.NET technology Note If you'reThis deleting, inserting, and updating data with known parameters, using Execute methods including ADO.NET internals, namespaces, classes, and is faster than using DataAdapter'sUpdate method.

interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ExecuteScalarADO.NET. is a handy method for using a SQL statement that retrieves a single value. A good

example of this is retrieving the number of rows from a database. Listing 4-16 retrieves the total number of rows from the Customers table. Then you assign the SQL command for getting the row count in Table Customers of Contents to the Command object, and you call ExecuteScalar to retrieve the counter. Applied ADO.NET—Building Data-Driven Solutions

Listing 4-16: Using the ExecuteScalar Method to Retrieve a Single Value Introduction Chapter 1

- ADO.NET Basics

Chapter ' Create 2 - Data a Components Connection in Visual Object Studio .NET

Dim ConnectionString As String = "Integrated Security=SSPI;" & _ Chapter 3 - ADO.NET in Disconnected Environments "Initial Catalog=Northwind;Data Source=MCB;" - ADO.NET in Connected Environments AsADO.NET SqlConnection = New SqlConnection(ConnectionString) ChapterDim 5 -conn Handling Events Chapter 4

an existing to the Database and Create a Chapter'6 open - Integrating XML with Connection ADO.NET Object with it: Chapter'7 Command - Data Binding and Windows Forms Data-Bound Controls conn.Open() - Constraints and Data Relations Dim cmd As SqlCommand = New SqlCommand("Customers", conn) Chapter 9 - ADO.NET Exception Handling ' Assign the SQL Insert statement we want to execute to the CommandText Chapter 10 - Working with the ODBC .NET Data Provider cmd.CommandText = "SELECT Count(*) FROM Customers" Chapter 11 - Stored Procedures and Views ' Call ExecuteNonQuery on the Command Object to execute insert Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Dim res As Integer Chapterres 13 -=Developing a Custom Data Provider cmd.ExecuteScalar() ChapterConsole.WriteLine("Total 14 - Developing Database Web Applications ASP.NET Rows :"using + res.ToString()) Chapter'15 Using ADO.NET in Xml Web Services release objects Chapterconn.Close() 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications conn.Dispose() Chapter 8

Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

If you run 4-17, it will display only the total row number on the console. Chapter 21 Listings - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Listing 4-17: DataReader Reads Data from a SQL Server Database


' Create a Connection Appendix C - ADO.NET FrequentlyObject Asked Questions Dim ConnectionString As String = "Integrated Security=SSPI;" & _ "Initial Catalog=Northwind;Data Source=MCB;" List of Figures Dim conn As SqlConnection = New SqlConnection(ConnectionString) List of Tables Dim SQL As String = "SELECT * FROM Customers" List of Listings ' open a connection List of Sidebars conn.Open() Dim cmd As SqlCommand = New SqlCommand(SQL, conn) ' Call ExecuteNonQuery on the Command Object to execute insert Dim res As Integer ' Call ExecuteReader to return a DataReader Dim reader As SqlDataReader = cmd.ExecuteReader() Console.WriteLine("Customer ID, Contact Name," & _ "Contact Title, Address") Console.WriteLine("===================================") While reader.Read() If Not reader.IsDBNull(0) Then Console.Write(reader("CustomerID").ToString() + ", ") Index

Console.Write(reader("ContactName").ToString() + ", ") Applied ADO.NET: Building Data-Driven Solutions+ ", ") Console.Write(reader("ContactTitle").ToString() ISBN:1590590732 by Mahesh Chand and David Talbot Console.WriteLine(reader("Address").ToString() + ", ") Apress © 2003 (928 pages) End If This text provides extensive coverage of ADO.NET technology End While including ADO.NET internals, namespaces, Console.WriteLine("Affected Records: " & _classes, and interfaces, and takes a comprehensive look at XML 'reader.RecordsAffected.ToString()) namespaces and classes, and how to integrate both with ' release objects ADO.NET. conn.Close() conn.Dispose() Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Using Other Command Methods Chapter 2 - Data Components in Visual Studio .NET Chapter 3 - ADO.NET Environments TheCancel method in of Disconnected a SqlCommand object tries to cancel an execute operation. If there's no execute Chapter 4 ADO.NET in Connected Environments operation or the Cancel method fails to cancel the execution, nothing happens. Chapter 5

- Handling ADO.NET Events TheCreateParameter method creates a SqlParameter object. Chapter 6 - Integrating XML with ADO.NET Chapter 7


ThePrepare method creates a prepared version of the command. It doesn't affect the operation if Chapter 8 - Constraints and Data Relations CommandType is TableDirect. Before calling this method, you need to specify the data type of each Chapter 9 - ADO.NET Exception Handling parameter in the statement to be prepared. Chapter 10 - Working with the ODBC .NET Data Provider

Chapter 11 - Stored Procedures and Viewsresets the command timeout value to the default value, which is TheResetCommandTimeout method Chapter 12 Oracle, SQLXML, and Other .NET Data Providers 30 seconds. Chapter 13 - Developing a Custom Data Provider

We use14these methodsDatabase in later examples. Chapter - Developing Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions The DataReader: Walking through the Data by Mahesh Chand and David Talbot

ISBN:1590590732

As discussed earlier in this chapter, there are two common ways to fetch data from a data source: using a Apress © 2003 (928 pages) DataSet and using a DataReader. A DataReader antechnology easy way for the programmer to read This text provides extensive coverage ofprovides ADO.NET data from a database as if it were coming from a stream. The DataReader is the solution for forwardincluding ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive at XML streaming data through ADO.NET. The DataReader look is also called a firehose cursor or forward, readnamespaces classes, and how to integrate both with onlycursor because it moves and forward through the data. The DataReader not only allows you to move ADO.NET. forward through each record of a database, but it also enables you to parse the data from each column. Similar to other data components, each data provider has a DataReader class. For example, OleDbDataReader is the DataReader class for OleDb data providers. Similarly, SqlDataReader and Applied ADO.NET—Building Data-Driven Solutions ODBC DataReader are DataReader classes for the Sql and ODBC data providers, respectively.

Table of Contents Introduction Chapter 1

- ADO.NET Basics

Chapter 3


Initializing DataReader Chapter 2 - Data a Components in Visual Studio .NET As you saw previously, you call the ExecuteReader method of the Command object, which returns an - ADO.NET in Connected Environments instance of the DataReader. For example, you use the following code:

Chapter 4 Chapter 5


Chapter 6


Dim cmd As SqlCommand = New SqlCommand(SQL, conn) - Data Binding and Windows Forms Data-Bound Controls ' Call ExecuteReader to return a DataReader Chapter 8 - Constraints and Data Relations Dim reader As SqlDataReader = cmd.ExecuteReader() Chapter 7 Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views call the Close method to close a DataReader: Once you're done with a DataReader, Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider reader.Close() Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Understanding DataReader Properties and Methods


Chapter 18 -describes Object-Relational Mapping inproperties, .NET Table 4-9 the DataReader and Table 4-10 describes the DataReader methods. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - The COMDataReader Interoperability and ADO.NET Table 4-9: Properties Chapter 21 - Messaging

PROPERTY

DESCRIPTION

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix Some DepthA - Relational Databases: Indicates the Basic depthConcepts of nesting for a row Appendix B - Commonly Used SQL Statements

FieldCount Returns number of columns in a row Appendix C - ADO.NET Frequently Asked Questions Index IsClosed List of Figures

Item

List of Tables ListRecordsAffected of Listings

Indicates whether a DataReader is closed Gets the value of a column in native format Number of rows affected after a transaction

List of Sidebars

Table 4-10: The DataReader Methods

METHOD


Close

by Mahesh Chand and David Talbot Closes a DataReader object. Apress © 2003 (928 pages)

ISBN:1590590732

This Represents text provides whether extensive a column coverage contains of ADO.NET null values. technology including ADO.NET internals, namespaces, classes, and Read Reads the next record in the DataReader. interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with NextResult ADO.NET. Advances the DataReader to the next result during batch transactions.

IsDBNull

There are dozens of GetXXX methods. These methods read a specific data Table of Contents type value from a column. For example, GetChar will return a column value as a character and GetString Applied ADO.NET—Building Data-Driven Solutions as a string. GetXXX


- ADO.NET Basics

- Data Components in Visual Studio .NET Reading with the DataReader

Chapter 2 Chapter 3

- ADO.NET in Disconnected Environments Once a4DataReader initialized,Environments you can utilize its various methods to read your data records. Foremost, Chapter - ADO.NET inisConnected

you can use the Read method, which, when called repeatedly, continues to read each row of data into the - Handling ADO.NET Events DataReader object. The DataReader also provides a simple indexer that enables you to pull each Chapter 6 - Integrating XML with ADO.NET column of data from the row. Listing 4-17 is an example of using the DataReader in the Northwind Chapter 7 - Data Binding and Windows Forms Data-Bound Controls database for the Customers table and displaying data on the console. Chapter 5

Chapter 8


Chapter Exception As you 9can- ADO.NET see, you use similarHandling steps as in previous examples. Initially, you create a Connection object, Chapter 10Command - Workingobject, with the ODBC .NET Data Provider method, call the DataReader'sRead method until create a call the ExecuteReader Chapter the end11 of -the Stored data,Procedures and then display and Views the data. At the end, you release the DataReader and

Connection objects. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

Figure 4-2 shows the output of Listing 4-17.

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Figure 4-2: Output of the Customers table from the DataReader

Index

List of Figures SqlDataReader provides many Read methods, which allow you to get the value of a column as a List of Tables specific type. For instance, you could rewrite this line from the previous example: List of Listings List of Sidebars

Dim str As String = reader("CustomerID").ToString()

as this: Dim str As String = reader.GetString(0)

With the GetString method of CustomerID, you don't need to do any conversion, but you do have to know the zero-based column number of CustomerID (which, in this case, is zero).

InterpretingApplied Batches of Building Queries ADO.NET: Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

TheDataReader also has methods that enable you to read data from a batch of SQL queries. The Apress © 2003 (928 pages) following is an example of a batch transaction on the Customers and Orders tables. The NextResult This text provides extensive coverage of ADO.NET technology method allows you to obtain each query result from the batch of queries performed on both tables. In this including ADO.NET internals, namespaces, classes, and example, after creating a Connection object, you setlook up your Command object to do a batch query on the interfaces, and takes a comprehensive at XML Customers and the Orders tables: namespaces and classes, and how to integrate both with ADO.NET.

Dim cmd as SqlCommand = new SqlCommand( * FROM Customers;SELECT * FROM Orders", Table"SELECT of Contents conn) Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1 can - ADO.NET Basics Now you create the Reader through the Command object. You then use a result flag as an indicator to Chapter - Datagone Components StudioThen .NET you loop through each stream of results and read the check if2 you've through in all Visual the results. Chapter 3 a-string ADO.NET Environments data into untilinit Disconnected reads 10 records. After that, you show results in a message box (see Listing 4-18). Chapter 4 - ADO.NET in Connected Environments

Listing54-18: Executing Batches Using DataReader Chapter - Handling ADO.NET Events Chapter 6


Chapter 7 - Data Binding and Windows ' Create a Connection ObjectForms Data-Bound Controls Chapter 8 - Constraints and Data Dim ConnectionString As Relations String = "Integrated Security=SSPI;" & _ Chapter "Initial 9 - ADO.NET Exception Handling Catalog=Northwind;Data Source=MCB;" Chapter Dim conn 10 - Working As SqlConnection with the ODBC .NET = New DataSqlConnection(ConnectionString) Provider

Dim SQL String = "SELECT Chapter 11 -As Stored Procedures and Views* FROM Customers; SELECT * FROM Orders" ' open connection Chapter 12 a- Oracle, SQLXML, and Other .NET Data Providers conn.Open() Chapter 13 - Developing a Custom Data Provider Dim cmd SqlCommand = Web NewApplications SqlCommand(SQL, conn) Chapter 14 -As Developing Database using ASP.NET ' Call onWeb the Command Object to execute insert Chapter 15 ExecuteNonQuery - Using ADO.NET in Xml Services Dim res As Integer ' Call ExecuteReader to return a DataReader Chapter 17 - Building Real-World Web Applications Dim reader As SqlDataReader = cmd.ExecuteReader() Chapter 18 - Object-Relational Mapping in .NET Dim str As String = "" Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Dim counter As Integer Chapter 20 - COM Interoperability and ADO.NET Dim bNextResult As Boolean = True Chapter - Messaging While21bNextResult = True Chapter 22 SQL Server and ADO.NET: Notes on Performance While -reader.Read() Appendix - Relational Databases: Some Basic Concepts + " ," strA += reader.GetValue(0).ToString() Appendix B - Commonly Used SQL counter = counter + 1Statements Appendix C - ADO.NET Frequently If counter = 10 Then Asked Questions Index Exit While End If List of Figures End While List of Tables ListMessageBox.Show(str) of Listings bNextResult = reader.NextResult() List of Sidebars End While ' release objects conn.Close() conn.Dispose() Chapter 16 - ASP.NET Server Controls and Data Binding

After that you call the NextResult method, which gets the next query result in the batch. The result is processed again in the Read method loop. The code displays data from both tables.

Applied ADO.NET: Solutionsdiscussion forums and newsgroups is Tip One of the commonly askedBuilding questionsData-Driven on ADO.NET-related ISBN:1590590732 by Mahesh Chand and David about when to use DataReader vs. Talbot when to use a DataSet. Here is a simple answer: You use a Apressinstead © 2003 (928 DataReader of apages) DataSet when you need read-only data and you don't need to alter coverage ADO.NET technology the data. This Seetext the provides "Using aextensive DataSet vs. Using of a DataReader" section for a more in-depth answer. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Understanding Command Behaviors

TheExecuteReader method of a Command object such as SqlCommand has two over-loaded forms, as shown:

Table of Contents


Overloads Public Function ExecuteReader() As SqlDataReader Overloads Public Function ExecuteReader(CommandBehavior) As SqlDataReader


- ADO.NET Basics

Chapter 2


Chapter 3 form - ADO.NET Disconnected Environments The first doesn'tintake any arguments, but the second form takes an argument of type Chapter 4 - ADO.NET inThe Connected Environments CommandBehavior. Command behavior can control the action and return data as a result of Chapter executing 5 a - Handling Command. ADO.NET Events Chapter 6


The default value passed in the ExecuteReader is CommandBehavior.Default, which returned the - Data Binding and Windows Forms Data-Bound Controls same results as ExecuteReader with no arguments.

Chapter 7 Chapter 8


Chapter 9 - ADO.NET Exception Handling WhenCommandBehavior.CloseConnection is passed in ExecuteReader, the associated Chapter 10 - Working the ODBC .NET Provider is closed. In this case, you don't have to call Connection objectwith is closed when the Data DataReader Chapter 11 - Stored Procedures and Views SqlConnection.Close explicitly. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

You can only a single row from database by executing a SqlCommand. The Chapter 13fetch - Developing a Custom Data aProvider CommandBehavior.SingleRow value passed in ExecuteReader returns the single row from a table Chapter 14 - Developing Database Web Applications using ASP.NET instead15 of -the result set. in Xml Web Services Chapter Using ADO.NET Chapter 16 - ASP.NET Server Controls and Data provides Binding a way for the DataReader to handle rows that CommandBehavior.SequentialAccess Chapter 17 Building Real-World Web Applications contain large binary values (BLOB data) such as images or memo fields. SequentialAccess values Chapter 18 - Object-Relational .NET of bytes or characters. enableDataReader to load Mapping data as ainstream Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

By setting CommandBehavior.KeyInfo Chapter 20 -the COM Interoperability and ADO.NET value, the DataReader doesn't return data. It returns the table column and primary key information instead. This is useful when you're collecting metadata. Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

TheCommandBehavior.SchemaOnly value returns column information only.

Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Applied ADO.NET: Building Solutions The DataAdapter: Adapting toData-Driven Your Environment by Mahesh Chand and David Talbot

ISBN:1590590732

As you saw in Figure 4-1, a DataAdapter plays a vital role in the ADO.NET architecture. It sits between a Apress © 2003 (928 pages) data source and a DataSet, and it passes data from of the data source to the DataSet, and vice versa, with This text provides extensive coverage ADO.NET technology or without using commands. Now you'll use disconnected classes such including ADO.NET internals, namespaces, classes, and as DataSet, DataTable, interfaces, and takes atocomprehensive look at XML applications based on Windows Forms DataView, and DataViewManager write interactive database and Web Forms.namespaces and classes, and how to integrate both with ADO.NET.

TheDataAdapter enables you to connect to a database and specify SQL strings for retrieving data from or writing data to a DataSet. As you know, a DataSet represents in-memory cached data. An in-memory Table of Contents object frees you from the confines of the specifics of a database and allows you to deal with the data in Applied ADO.NET—Building Data-Driven Solutions memory. The DataAdapter serves as an intermediary between the database and the DataSet. Introduction Chapter 1

- ADO.NET Basics

Chapter 3


Constructing a DataAdapter Chapter 2 - Data Components in Visual Studio Object .NET TheDataAdapter constructor has many overloaded forms. You can create a DataAdapter using a - ADO.NET in Connected Environments constructor with no arguments, pass a Command object, pass a Command object with Connection object as Chapter 5 - Handling ADO.NET Events arguments, or use a combination of these. You can also specify a SQL statement as a string for querying a Chapter 6 table - Integrating particular or moreXML thanwith oneADO.NET table. You can also specify the connection string or a Connection object Chapter 7 Data Binding and Windows Forms Data-Bound Controls to connect to the database. Listing 4-19 creates four SqlDataAdapter instances with different approaches. Chapter andfirst Data Relations As you 8can- Constraints see, the code creates and opens SqlConnection and SqlCommand objects. Later you use Chapter 9 -objects ADO.NET Exception Handling these two to create DataAdapters. The first DataAdapter,da1, takes only one parameter of type Chapter 10 - Working with SqlCommand the ODBC .NETalready Data Provider SqlCommand. Because has a SqlConnection, there's no need to specify a Chapter connection 11 - explicitly Stored Procedures with the DataAdapter. and Views The second DataAdapter,da2, is created using no argument, laterSQLXML, its SelectCommand property is set to a SqlCommand. The third DataAdapter,da3, Chapter 12 -and Oracle, and Other .NET Data Providers takes a string argument as a SQL statement and a second argument as SqlConnection. The last Chapter 13 - Developing a Custom Data Provider DataAdapter takes both string arguments, one containing the SQL statement and the second containing Chapter 14 - Developing Database Web Applications using ASP.NET the connection string. Chapter 15 - Using ADO.NET in Xml Web Services Chapter 4


Listing 4-19: CreatingSqlDataAdapter Instances


' Create a Connection Object Considerations and Data Binding Chapter 19 - Mapped Objects: Performance Dim ConnectionString As and String = "Integrated Security=SSPI;" & _ Chapter 20 - COM Interoperability ADO.NET "Initial Catalog=Northwind;Data Source=MCB;" Dim conn As SqlConnection = New SqlConnection(ConnectionString) Chapter 22 - SQL Server and ADO.NET: Notes on Performance Dim SQL As String = "SELECT * FROM Customers" Appendix A - Relational Databases: Some Basic Concepts ' open a connection Appendix B - Commonly Used SQL Statements conn.Open() Appendix C - ADO.NET Frequently Asked Questions Dim cmd As SqlCommand = New SqlCommand(SQL, conn) Index ' Creating SqlDataAdapter using different constructors List of Figures Dim da1 As SqlDataAdapter = New SqlDataAdapter(cmd) List of Dim Tables da2 As SqlDataAdapter = New SqlDataAdapter() List of Listings da2.SelectCommand = cmd List of Sidebars Dim da3 As SqlDataAdapter = New SqlDataAdapter(SQL, conn) Dim da4 As SqlDataAdapter = New SqlDataAdapter(SQL, ConnectionString) Chapter 21 - Messaging

As discussed, there's no difference between creating OleDb, Sql, and Odbc DataAdapters. The only difference is the connection string. For example, Listing 4-20 shows you how to create an OleDbDataAdapter object. Listing 4-20 uses the Access 2000 Northwind database and accesses all records of the Orders table by using a SELECT * SQL query. Listing 4-20: Executing a SELECT * Statement Using OleDbDataAdapter

' Create a Connection Object Applied ADO.NET: Building Data-Driven Solutions Dim ConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _ ISBN:1590590732 by Mahesh Chand and David Talbot "Data Source=c:\\Northwind.mdb" Apress ©=2003 (928 pages)* FROM Orders" Dim SQL As String "SELECT This text provides extensive coverage of ADO.NET technology Dim conn As OleDbConnection = New OleDbConnection(ConnectionString) including ADO.NET internals, namespaces, classes, and ' Open the connection interfaces, and takes a comprehensive look at XML conn.Open() namespaces and classes, and how to integrate both with ' Create an OleDbDataAdapter object ADO.NET. Dim adapter As OleDbDataAdapter = New OleDbDataAdapter() adapter.SelectCommand = New OleDbCommand(SQL, conn) Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction

You can use a DataAdapter's Command properties by using the Command object with Chapter 1 also - ADO.NET Basics OleDbDataAdaper. For example, theStudio following Chapter 2 - Data Components in Visual .NETcode uses OleDbCommand to set the SelectCommand property DataAdapter. You can see that OleDbDataAdapter has no arguments as its constructor: Chapter 3 of- the ADO.NET in Disconnected Environments Chapter 4


Chapter ' Create 5 - Handling an OleDbDataAdapter ADO.NET Events object

Dim adapter As OleDbDataAdapter = New OleDbDataAdapter() Chapter 6 - Integrating XML with ADO.NET adapter.SelectCommand = New Forms OleDbCommand(SQL, Chapter 7 - Data Binding and Windows Data-Bound Controlsconn) Chapter 8


Chapter 9


Understanding DataAdapter Properties


As you 12 start workingSQLXML, with DataAdapters, take a quick look at the DataAdapter properties and Chapter - Oracle, and Other .NETyou Dataneed Providers methods. DataAdapter has fourProvider properties that are Command objects; they represent the ways it can Chapter 13 The - Developing a Custom Data query, insert, delete, and updateWeb the database. Chapter 14 - Developing Database Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Table 4-11 describes SqlDbDataAdapter class properties, and Table 4-12 shows the

Chapter 16 - ASP.NET Server Controls and Data Binding OleDbDataAdapter properties. Chapter 17 - Building Real-World Web Applications

Chapter 18 - Object-Relational Mapping Class in .NETProperties Table 4-11: The SqlDataAdpater Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

PROPERTY DESCRIPTION Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging AcceptChangesDuringFill

TheAcceptChanges method of a DataRow saves the changes

Chapter 22 - SQL Server and ADO.NET:made Notes to onaPerformance DataRow. The True value of this property makes a Appendix A - Relational Databases: Some Basic Concepts call to the DataRow'sAcceptChanges property after it has Appendix B - Commonly Used SQL Statements been added to the DataTable. The False value doesn't. The Appendix C - ADO.NET Frequently Askeddefault Questions value is True. Index

ContinueUpdateOnError


List of Listings ListDeleteCommand of Sidebars

InsertCommand

TheTrue value of this property keeps the update process continuing even if an error occurred in a DataRow. The False value generates an exception. The default value is False. Represents a DELETE statement or stored procedure for deleting records from the data source. Represents an INSERT statement or stored procedure for inserting a new record to the data source.

MissingSchemaAction Determines the action Solutions to be taken when incoming data doesn't Applied ADO.NET: Building Data-Driven have a matching schema. This is a type of ISBN:1590590732 by Mahesh Chand and David Talbot MissingMappingAction enumeration, which has three Apress © 2003 (928 pages) values:Error,Ignore, and Passthrough. The Error value This text provides extensive coverage of ADO.NET technology generates an exception, the Ignore value maps the unmatched including ADO.NET internals, namespaces, classes, and or tables, andatthe Passthrough value adds the interfaces, and takes columns a comprehensive look XML namespaces and classes, andcolumn how to or integrate source sourceboth tablewith created to the DataSet using its ADO.NET. original name. Determines the action to be taken when a DataSetschema is missing. This is a type of MissingSchemaAction Applied ADO.NET—Building Data-Driven enumeration, Solutions which has three values: AddWithKey,Error, and Introduction Ignore.AddWithKey adds the necessary columns and Chapter 1 - ADO.NET Basics primary key information, Error generates an exception, and Chapter 2 - Data Components in VisualIgnore Studio .NET ignores the extra columns. MissingActionSchema

Table of Contents

Chapter 3


Chapter 4


SelectCommand

Chapter 5

Represents a SELECT statement or stored procedure for selecting records from a data source.

- Handling ADO.NET Events UpdateCommand Represents an UPDATE statement or stored procedure for Chapter 6 - Integrating XML with ADO.NET Chapter 7

records in Controls a data source. - Data Binding and Windowsupdating Forms Data-Bound

Chapter 8 - Constraints and Data Relations TableMappings Chapter 9

Represents a collection of mappings between an actual data

- ADO.NET Exception Handling source table and a DataTable object. Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET DataProperties Providers with Examples Table 4-12: OleDbDataAdapter Command Chapter 13 - Developing a Custom Data Provider

PROPERTY EXAMPLEWeb Applications using ASP.NET Chapter 14 - Developing Database Chapter 15 - Using ADO.NET in Xml Web Services SelectCommand cmd.SelectCommand.CommandText = "SELECT * FROM Orders Chapter 16 - ASP.NET Server Controls and Data Binding ORDER BY Price"; Chapter 17 - Building Real-World Web Applications

DeleteCommand

cmd.DeleteCommand.CommandText = "DELETE FROM Orders WHERE LastName ='Smith'";



Chapter 20 - COM Interoperability and ADO.NET InsertCommand cmd.InsertCommand.CommandText = "INSERT INTO Orders Chapter 21 - Messaging VALUES (25,'Widget1','Smith')"; Chapter 22 - SQL Server and ADO.NET: Notes on Performance

UpdateCommand

cmd.UpdateCommand.CommandText = "UPDATE Orders SET ZipCode='34956' WHERE OrderNum =14";



Listing 4-21 sets some of the SqlDataAdapter properties.

Index

List of Figures Listing 4-21: UsingSqlDataAdapter Properties List of Tables List of Listings

' Create an OleDbDataAdapter object

List ofDim Sidebars adapter As SqlDataAdapter = New SqlDataAdapter()

adapter.SelectCommand = New SqlCommand(SQL, conn) adapter.AcceptChangesDuringFill = True adapter.ContinueUpdateOnError = True adapter.MissingSchemaAction = MissingSchemaAction.Error adapter.MissingMappingAction = MissingMappingAction.Error

Understanding DataAdapter Methods TheDataAdapter class provides many useful methods. For instance, the Fill method of the

DataAdapter fills data from a DataAdapter to the DataSet object, and the Update method stores data Building Data-Driven Solutions from a DataSetApplied object toADO.NET: the data source. by Mahesh Chand and David Talbot

ISBN:1590590732

Table 4-13 describes Apress some © 2003 of(928 thepages) OleDbDataAdapter methods. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Table 4-13: The DataAdapter Methods

interfaces, and takes a comprehensive look at XML namespaces DESCRIPTION and classes, and how to integrate both with ADO.NET.

METHOD Fill Table of Contents

Fills data records from a DataAdapter to a DataSet object depending on the selection query.

FillSchema This method adds a DataTable to a DataSet and configures the Applied ADO.NET—Building Data-Driven Solutions Introduction

schema to match that in the data source.

Chapter 1 - ADO.NET Basics This method retrieves parameters that are used when a SELECT GetFillParameters Chapter 2 - Data Componentsstatement in Visual Studio .NET is executed. Chapter 3


Update - ADO.NET in Connected This method stores data from a DataSet to the data source. Environments

Chapter 4 Chapter 5


Chapter 6


Filling -the Data DataSet Binding and Windows Forms Data-Bound Controls

Chapter 7 Chapter 8


TheFill method is the primary method for bringing data into a DataSet from a data source. This - ADO.NET Exception Handling command uses the SelectCommand SQL statement to fill a DataSet memory structure consisting of Chapter 10 - Working with the ODBC .NET Data Provider DataTables, DataRows, DataColumns, and DataRelations. The Fill method has eight overloaded Chapter 11 - Stored Procedures and Views forms. Using these methods, you can fill a DataSet from a DataAdapter by selecting a particular table, Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers selecting a range of rows, and selecting rows based on the CommandBehavior. The following shows Chapter 13 - Developing a Custom Data Provider different overloaded forms of the Fill method defined in the DbDataAdapter class: Chapter 9


Overloads Overrides Public Function Fill(DataSet) As Integer _ Implements IDataAdapter.Fill Chapter 17 - Building Real-World Web Applications Overloads Public Function Fill(DataTable) As Integer Chapter 18 - Object-Relational Mapping in .NET Overloads Public Function Fill(DataSet, String) As Integer Chapter 19 - Mapped Objects: Performance Considerations Data Binding Overloads Overridable Protected Function and Fill(DataTable, IDataReader) _ Chapter 20 COM Interoperability and ADO.NET As Integer Chapter 21 - Messaging Overloads Overridable Protected Function Fill(DataTable, _ Chapter 22 - SQL Server and ADO.NET: Notes Performance IDbCommand, CommandBehavior) As on Integer Appendix A Relational Databases: Some Basic Concepts Overloads Public Function Fill(DataSet, Integer, Integer, String) _ Appendix As IntegerOverloads B - Commonly Used SQL Statements Overridable Protected Fill(DataSet, String, IDataReader, _ Appendix C - ADO.NET FrequentlyFunction Asked Questions Integer, Integer) As IntegerOverloads Index Overridable Protected Function Fill(DataSet, Integer, Integer, _ List of Figures ListString, of Tables IDbCommand, CommandBehavior) As Integer Chapter 16 - ASP.NET Server Controls and Data Binding


The following form of the Fill method selects or refreshes rows in a specified range in the DataSet: Overloads Public Function Fill(_ ByVal dataSet As DataSet, _ ByVal startRecord As Integer, _ ByVal maxRecords As Integer, _ ByVal srcTable As String _ ) As Integer

In this example, dataSet is a DataSet,startRecord is the zero-based record number to start with, maxRecords is the maximum number of records to retrieve, and srcTable is the name of the source table

to use for table mapping. The following code calls the same overloaded method to get or refresh rows from Data-Driven Solutions the 9th position toApplied the 15th ADO.NET: position of Building the Orders table. In other words, it fills the DataSet with seven rows if ISBN:1590590732 by Mahesh Chand and David Talbot found in the table: Apress © 2003 (928 pages)


adapter.Fill(ds, 9, 15, " Orders") including ADO.NET internals, namespaces, classes, and

interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with You can use a DataSet ADO.NET.directly or a DataTable to fill or refresh the data of a DataSet. Listing 4-22 calls

theFill method to fill data to a DataSet, which later can bind with data-bound controls. Table of Contents Listing 4-22: Calling a DataAdapter'sFill Method Applied ADO.NET—Building Data-Driven Solutions Introduction

' Create an OleDbDataAdapter object - ADO.NET Basics Dim adapter As SqlDataAdapter = New SqlDataAdapter() Chapter 2 - Data Components in Visual Studio .NET adapter.SelectCommand = New SqlCommand(SQL, conn) Chapter 3 - ADO.NET in Disconnected ' Create DataSet Object Environments Chapter in Connected Dim4 ds- ADO.NET As DataSet = NewEnvironments DataSet("Orders") Chapter 5 - Handling ADO.NET Events ' Call DataAdapter's Fill method to fill data from the Chapter 6 - Integratingto XMLthe with DataSet ADO.NET ' DataAdapter Chapter adapter.Fill(ds) 7 - Data Binding and Windows Forms Data-Bound Controls Chapter 1

Chapter 8


Chapter 9



Adding a DataTable to a DataSet

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter TheFillSchema 13 - Developing method a Custom adds aData DataTable Provider to a DataSet. The FillSchema method has two

arguments; the first is DataTable, the second is SchemaType. The SchemaType argument defines Chapter 14 - Developing Database Weband Applications using ASP.NET the handling of existing schema. has Services two values: Mapped and Source. The SchemaType.Mapped value Chapter 15 - Using ADO.NET in XmlItWeb means16 you- can applyServer any existing table to the incoming schema and configure the DataSet with Chapter ASP.NET Controls and mapping Data Binding the transformed schema. The SchemaType.Source value means you can ignore any table mappings on Chapter 17 - Building Real-World Web Applications theDataAdapter and configure the DataSet using the incoming schema without applying any Chapter 18 - Object-Relational Mapping in .NET transformations. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter - COM and method ADO.NETto add a DataTable to a DataSet. Listing 20 4-23 usesInteroperability the FillSchema Chapter 21 - Messaging Chapter Listing22 4-23: - SQL Using Server theand FillSchema ADO.NET: Notes Method on Performance of SqlDataAdapter Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements ' Create an OleDbDataAdapter object Appendix C - ADO.NET Frequently Asked Questions Dim adapter As SqlDataAdapter = New SqlDataAdapter() Index adapter.SelectCommand = New SqlCommand(SQL, conn) List Figures DataSet Object ' of Create List of Tables Dim ds As DataSet = New DataSet("Orders") List ' of Call Listings DataAdapter's Fill method to fill data from the

' of DataAdapter to the DataSet List Sidebars adapter.Fill(ds) ' Adding a DataTable to the DataSet Dim table As DataTable() = _ adapter.FillSchema(ds, SchemaType.Mapped, "Categories")

Looking at a DataAdapter Example Now you'll create your first sample using DataAdapters. In this example, you'll learn how to create DataAdapters using the Sql and OleDb data providers and fill data from a DataAdapter to a DataGrid

control.


First, create a Windows by Mahesh application Chand and using David Visual Talbot Basic ProjectsISBN:1590590732 and add two Button controls and a DataGrid control Apress to the© form 2003 (928 by pages) dragging the controls from the Toolbox. Second, set both buttons' Name property; use OleDbDataAdapter and SqlDataAdapter. Next, set the Text properties to This text provides extensive coverage of ADO.NET technology including internals, namespaces, classes, OleDbDataAdapter andADO.NET SqlDataAdapter. After setting theseand properties, the form will look like Figure 4interfaces, a comprehensive look at XML 3. As you can see, there areand twotakes buttons, shown as OleDbDataAdapter and SqlDataAdapter. namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Figure 4-3: Creating a Windows Forms application and adding controls to the form

Chapter 10 button - Working thehandlers ODBC .NET Now add clickwith event for Data both Provider the OleDbDataAdapter and SqlDataAdapter buttons. You can Chapter 11 Stored Procedures and Views add a button click event handler either by double-clicking the button or by using the Events tab of the Chapter 12 -window. Oracle, SQLXML, and Other .NET Data Providers Properties On the OleDbDataAdapter button click event handler, you'll write code to read data from an OleDb data source and fill data to the DataGrid control. On the SqlDataAdapter button click event Chapter 13 - Developing a Custom Data Provider

handler, write code to readWeb dataApplications from a SQLusing Server data source and fill data to the DataGrid. Chapter 14you'll - Developing Database ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Listing 4-24 shows the source code for the OleDbDataAdapter button click, and Listing 4-25 shows the source code for the SqlDataAdapter button click. As you can see, you follow the same steps as before. Chapter 17 - Building Real-World Web Applications Open a connection, create a DataAdapter object with a SELECT string, create a DataSet object, call a Chapter 18 - Object-Relational Mapping in .NET DataAdapter'sFill method to fill the DataSet, and bind the DataSet to the DataGrid control using Chapter 19 - Mapped Objects: Performance Considerations and Data Binding theDataGrid.DataSouce property of DataSet.DefaultViewManager, which represents the default Chapter 20 COM Interoperability and ADO.NET view of a DataSet object. Chapter 16 - ASP.NET Server Controls and Data Binding


Listing22 4-24: Displaying OrdersNotes TableonData in a DataGrid Using OleDbDataAdapter Chapter - SQL Server andthe ADO.NET: Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B -Sub Commonly Used SQL Statements Private OleDbDataAdapter_Click(ByVal sender As System.Object, _ Appendix Frequently Asked Questions ByValC e- ADO.NET As System.EventArgs) Handles OleDbDataAdapter.Click Index' Create a Connection Object List ofDim Figures ConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _ List of"Data Tables Source=c:\\Northwind.mdb"

SQL As String = "SELECT * FROM Orders" List ofDim Listings conn As OleDbConnection = New OleDbConnection(ConnectionString) List ofDim Sidebars ' Open the connection conn.Open() ' Create an OleDbDataAdapter object Dim adapter As OleDbDataAdapter = New OleDbDataAdapter() adapter.SelectCommand = New OleDbCommand(SQL, conn) ' Create DataSet Object Dim ds As DataSet = New DataSet("Orders") ' Call DataAdapter's Fill method to fill data from the ' DataAdapter to the DataSet adapter.Fill(ds) ' Bind data set to a DataGrid control

DataGrid1.DataSource = ds.DefaultViewManager Applied ADO.NET: Building Data-Driven Solutions End Sub by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, and Listing 4-25: Displaying the Customers Table's Data inclasses, a DataGrid Using SqlDataAdapter interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET. Private Sub SqlDataAdapter_Click(ByVal sender As System.Object, _

ByVal e As System.EventArgs) Handles SqlDataAdapter.Click ' Create a Connection Object Table of Contents Dim ConnectionString As String = "Integrated Security=SSPI;" & _ Applied ADO.NET—Building Data-Driven Solutions "Initial Catalog=Northwind;Data Source=MCB;" Introduction Dim conn As SqlConnection = New SqlConnection(ConnectionString) Chapter 1 - ADO.NET Basics Dim SQL As String = "SELECT * FROM Customers" Chapter 2 - Data Components in Visual Studio .NET ' Open the connection Chapter 3 - ADO.NET in Disconnected Environments conn.Open() Chapter 4 - ADO.NET in Connected Environments ' Create an OleDbDataAdapter object Chapter 5 Handling ADO.NET Events Dim adapter As SqlDataAdapter = New SqlDataAdapter() Chapter 6 - Integrating XML with ADO.NET adapter.SelectCommand = New SqlCommand(SQL, conn) Chapter 7 - Data DataSet Binding andObject Windows Forms Data-Bound Controls ' Create Chapter Dim 8 ds - Constraints As DataSet and Data = New Relations DataSet("Orders") ' Call DataAdapter's Fill method to fill data from the Chapter 9 - ADO.NET Exception Handling ' DataAdapter Chapter 10 - Working withto thethe ODBCDataSet .NET Data Provider adapter.Fill(ds) Chapter 11 - Stored Procedures and Views ' Adding a SQLXML, DataTable to the Chapter 12 - Oracle, and Other .NETDataSet Data Providers Dim table As DataTable() = _ Chapter 13 - Developing a Custom Data Provider adapter.FillSchema(ds, SchemaType.Mapped, "Categories") Chapter 14 - Developing Database Web Applications using ASP.NET ' Bind data set to a DataGrid control Chapter 15 - Using ADO.NET in Xml Web Services DataGrid1.DataSource = ds.DefaultViewManager Chapter 16 - ASP.NET Server Controls and Data Binding End Sub Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - of COM Interoperability ADO.NET The output Listing 4-24 looks and like Figure 4-4. Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 4-4: Filling data from an Access database to a DataGrid control using OleDbDataAdapter The output of Listing 4-25 looks like Figure 4-5.


ISBN:1590590732


Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction

Figure Filling data from a SQL Server database to a DataGrid control using SqlDataAdapter Chapter 1 - 4-5: ADO.NET Basics Chapter 2


Chapter 3


Filling -the ADO.NET DataAdapter in Connected Environments from a Recordset

Chapter 4 Chapter 5

- Handling ADO.NET Events Because realized it would be difficult for some developers to let go of their ADO recordsets (or Chapter 6 Microsoft - Integrating XML with ADO.NET

perhaps they have some legacy applications or components that would be difficult to convert), the - Data Binding and Windows Forms Data-Bound Controls DataAdapter'sFill method also allows you to fill a DataSet with an ADO recordset. You can't, however, Chapter 8 - Constraints and Data Relations go the other way and fill a recordset with a Dataset. The Fill method appends rows from the recordset to Chapter 9 - ADO.NET Exception Handling the existing DataSet'sDataTable. If a primary key exists for the DataRows in the DataSet, then the Fill Chapter 10 - Working with the ODBC .NET Data Provider method will attempt to update rows from the recordset with a matching primary key. You can call the Chapter 11 - Stored Procedures and Views recordset with the |following code: Chapter 7


OleDbDataAdapter1.Fill(ds,

anADORecordset, SourceTableName)

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Updating the Database Using the Update Method


The architecture of a DataAdapter has been designed so that you can make any changes you want to the data in a filled DataSet, without affecting the database until you call the Update method. When Update is Chapter COM Interoperability and ADO.NET called, 20 the-DataAdapter will attempt to execute each query (UPDATE,INSERT,DELETE) on every row of Chapter 21 Messaging theDataSet that has been updated, inserted, and deleted. For example, if you call Delete on a row in the Chapter 22 -then SQL when ServerUpdate and ADO.NET: Notes on Performance DataSet, is called on the DataAdapter, the DeleteCommand of the DataAdapter Appendix A Relational Databases: Some Basic Concepts will be called using the particular row in the DataSet. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding


NoteC Keep in mind that this Asked Update is different from a SQL UPDATE statement. Appendix - ADO.NET Frequently Questions Index

To delete a row, you create an SqlCommand object with a DELETE statement and set the DeleteCommand property of the DataAdapter.Listing 4-26 creates a SqlCommand object with a DELETE statement where List of Tables EmployeeId = 10. List of Figures

List of Listings

List of Sidebars Listing 4-26: Setting the DeleteCommand Property of DataAdapter

' Set DeleteCommand property adapter.DeleteCommand = New SqlCommand( "DELETE from Employees where EmployeeID = 10", conn)

Also, you need to create a parameter for the command that maps to the EmployeeID in the database. (We discuss parameters in more depth in the "Staying within the Parameters" section of this chapter.) Listing 4-27 shows an example that creates and sets parameter properties for the Sql data provider.

Listing 4-27: Creating a SqlParameter


ISBN:1590590732

Dim workParamApress As SqlParameter = Nothing © 2003 (928 pages) adapter.DeleteCommand = New SqlCommand(_ This text provides extensive coverage of ADO.NET technology "DELETE from including Employees where EmployeeID = classes, 10", conn) ADO.NET internals, namespaces, and and takes a comprehensive look at XML workParam = interfaces, adapter.DeleteCommand.Parameters.Add(_ namespaces and classes, and how to integrate both with "@EmployeeID", OleDbType.Integer) ADO.NET. workParam.SourceColumn = "EmployeeID" workParam.SourceVersion = DataRowVersion.Original Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction

Now you create a DataSet and fill it with the employees from the Employees table in the Northwind - ADO.NET Basics database, as shown in Listing 4-28.

Chapter 1 Chapter 2


Chapter - ADO.NET Disconnected Environments Listing34-28: Callinginthe Fill Method of a DataAdapter Chapter 4


Chapter 5


Dim ds As DataSet = New DataSet("EmployeeSet") - Integrating XML with ADO.NET adapter.Fill(ds, "Employees")

Chapter 6 Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working the ODBC Provider Now you're preparedwith to delete data.NET fromData a table using a DataTable. By calling Delete on the last row in Chapter theRows 11collection, - Stored Procedures you mark and the last Views row as deleted. To cause the actual deletion to take place in the

Northwind you need call Update onProviders the adapter. This causes the adapter to go through each Chapter 12 -database, Oracle, SQLXML, andtoOther .NET Data changed of the DataSet and seeProvider which command needs to be called on that row. In the case of the last Chapter 13row - Developing a Custom Data row in the you Web call the DeleteCommand (see Listing 4-29). Chapter 14 -Employees Developingtable, Database Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Listing 4-29: Removing a Row and Calling the Update Method of a DataAdapter


Dim Dt DataTable =Mapping ds.Tables("Employees") Chapter 18 As - Object-Relational in .NET Dim lastRow As Objects: Integer = Dt.Rows.Count - and 1 Data Binding Chapter 19 - Mapped Performance Considerations Dim firstName As String and = Dt.Rows(lastRow)("FirstName").ToString() Chapter 20 - COM Interoperability ADO.NET Dim lastName As String = Dt.Rows(lastRow)("LastName").ToString() Dt.Rows(Dt.Rows.Count - 1).Delete() Chapter 22 - SQL Server and ADO.NET: Notes on Performance adapter.Update(ds, "Employees") Chapter 21 - Messaging


Index Listing 4-30 shows the code that calls the Update method to delete a row from a DataSet and updates it List of Figures back to the database using DataApdater'sUpdate method. List of Tables

Listing 4-30: Calling a DataAdapter's Update Method List of Listings List of Sidebars

Dim ConnectionString As String = "Integrated Security=SSPI;" & _ "Initial Catalog=Northwind;Data Source=MCB;" Dim conn As SqlConnection = New SqlConnection(ConnectionString) Dim adapter As SqlDataAdapter = New SqlDataAdapter() Dim workParam As SqlParameter = Nothing adapter.DeleteCommand = New SqlCommand(_ "DELETE from Employees where EmployeeID = 10", conn) workParam = adapter.DeleteCommand.Parameters.Add(_ "@EmployeeID", OleDbType.Integer) workParam.SourceColumn = "EmployeeID" workParam.SourceVersion = DataRowVersion.Original

adapter.SelectCommand = New SqlCommand("SELECT * FROM Employees", conn) ADO.NET: Data-Driven Solutions Dim ds As Applied DataSet = New Building DataSet("EmployeeSet") ISBN:1590590732 by Mahesh Chand and David Talbot adapter.Fill(ds, "Employees") Apress © 2003 (928 pages) Dim Dt As DataTable = ds.Tables("Employees") ThisAs textInteger provides extensive coverage of ADO.NET Dim lastRow = Dt.Rows.Count - 1 technology including ADO.NET internals, namespaces, classes, and Dim firstName As String = Dt.Rows(lastRow)("FirstName").ToString() interfaces, and takes a comprehensive look at XML Dim lastName As String = Dt.Rows(lastRow)("LastName").ToString() namespaces and classes, and how to integrate both with Dt.Rows(Dt.Rows.Count - 1).Delete() ADO.NET. adapter.Update(ds, "Employees") DataGrid1.DataSource = ds.DefaultViewManager Table ' of release Contents objects Applied ADO.NET—Building Data-Driven Solutions conn.Close() Introduction conn.Dispose() Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4

- ADO.NET in Connected Environments Table and Column Mapping - Handling ADO.NET Events

Chapter 5

Chapter Integratingproperties XML with of ADO.NET One of 6the- important the DataAdapter is the TableMappings property. This property Chapter 7 Data Binding and Windows Forms Data-Bound Controls contains a collection of DataTableMapping objects (from the System.Data.Common namespace). The Chapter DataAdapter 8 - Constraints uses theand DataTableMapping Data Relations object to map the table name of the data source to the

DataTable name ofException the DataSet. In general, the names for both sources can be the same. Chapter 9 - ADO.NET Handling Chapter 10 - Working with the ODBC .NET Data Provider

For example, Listing 4-31 constructs the Northwind database's Order Table Mapping and adds it to the DataAdapter.



Chapter - Developing a Custom Data Provider Listing13 4-31: UsingDataTableMapping to Map the Orders Table of Northwind Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

' Create a Connection Object Dim ConnectionString As String = "Integrated Security=SSPI;" & _ Chapter 17 - Building Real-World Web Applications "Initial Catalog=Northwind; Data Source=MCB;" Chapter 18 - Object-Relational Mapping in .NET Dim conn As SqlConnection = New SqlConnection(ConnectionString) Chapter'19 - Mapped Performance Considerations and Data Binding Open the Objects: connection Chapterconn.Open() 20 - COM Interoperability and ADO.NET Chapter'21 - Messaging Create a DataTableMapping object ChapterDim 22 -dtMapping SQL Server and Notes on Performance AsADO.NET: DataTableMapping = Appendix A New - Relational Databases: Some Basic Concepts"mapOrders") DataTableMapping("Orders", Appendix Dim B -adapter Commonly As Used SqlDataAdapter SQL Statements = SqlDataAdapter("Select Appendix C -New ADO.NET Frequently Asked Questions * From Orders", conn) Index ' Call DataAdapter's TableMappings.Add method adapter.TableMappings.Add(dtMapping) List of Figures ' Create a DataSet Object and call DataAdapter's Fill method List of Tables ' Make sure you use new name od DataTableMapping i.e., MayOrders List of Listings Dim ds As DataSet = New DataSet() List of Sidebars adapter.Fill(ds, "mapOrders") DataGrid1.DataSource = ds.DefaultViewManager 'Dispose conn.Close() conn.Dispose() Chapter 16 - ASP.NET Server Controls and Data Binding

The default mapping for a DataTable is the Table alias. If you use this mapping name, then you don't need to mention the table in the Fill method. Listing 4-32 shows an example using DataTableMapping with the Table option.

Listing 4-32: UsingDataTableMapping with the Table Option


ISBN:1590590732

' Create a Connection Object Apress © 2003 (928 pages) Dim ConnectionString As String = "Integrated Security=SSPI;" & _ This text provides extensive coverage of ADO.NET technology "Initial including Catalog=Northwind; Source=MCB;" ADO.NET internals,Data namespaces, classes, and Dim conn interfaces, As SqlConnection = New SqlConnection(ConnectionString) and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ' Open the connection ADO.NET. conn.Open() ' Create a DataTableMapping object Dim dtMapping As DataTableMapping = Table of Contents New DataTableMapping("Table", "mapOrders") Applied ADO.NET—Building Data-Driven Solutions Dim adapter As SqlDataAdapter = Introduction New SqlDataAdapter("Select * From Orders", conn) Chapter 1 - ADO.NET Basics ' Call DataAdapter's TableMappings.Add method Chapter 2 - Data Components in Visual Studio .NET adapter.TableMappings.Add(dtMapping) Chapter 3 - ADO.NET in Disconnected Environments ' Create a DataSet Object and call DataAdapter's Fill method Chapter'4 Make - ADO.NET Connected Environments sure inyou use new name od DataTableMapping i.e., MayOrders ChapterDim 5 -ds Handling ADO.NET Events As DataSet = New DataSet() Chapteradapter.Fill(ds) 6 - Integrating XML with ADO.NET ChapterDataGrid1.DataSource 7 - Data Binding and Windows Forms Data-Bound Controls = ds.DefaultViewManager Chapter'Dispose 8 - Constraints and Data Relations Chapterconn.Close() 9 - ADO.NET Exception Handling Chapterconn.Dispose() 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

DataTables are not the only things aliased in ADO.NET. You can also alias the DataColumns using DataColumnMapping objects. Why do you want column mapping? Let's say you have a table that has Chapter 15 - Using ADO.NET in Xml Web Services column names such as a1, a2, and so on, but when a user views the data in data-bound controls, you want Chapter 16 - ASP.NET Server Controls and Data Binding to display some meaningful names such as CustomerName and so on. Chapter 14 - Developing Database Web Applications using ASP.NET


Chapter 18 - Object-Relational in .NET Data column mapping allowsMapping you to customize a DataSet's column names, which internally are mapped Chapter 19 - Mapped Objects: Performance Considerations and Data Binding with a table columns. You can achieve this by using

DataAdapter.DataTableMapping.ColumnMapping. The DataColumnMapping property of Chapter 20 - COM Interoperability and ADO.NET DataTableMapping Chapter 21 - Messaging is a collection of column mappings. You use the Add method of DataColumnCollection, which adds a column mapping. The Add method takes a column name of the Chapter 22 - SQL Server and ADO.NET: Notes on Performance source table and a DataSet column Listing 4-33 maps the OrderId,ShipName,ShipCity, and Appendix A - Relational Databases: Somename. Basic Concepts OrderDate columns of theSQL Orders table to mapID,mapName,mapCity, and mapDate, respectively. Appendix B - Commonly Used Statements Appendix C - ADO.NET Frequently Asked Questions

Listing 4-33: UsingDataColumnMapping

Index

List of Figures

' of Create List Tables a Connection Object Dim ConnectionString As String = "Integrated Security=SSPI;" & _ "Initial Catalog=Northwind; Data Source=MCB;" List of Sidebars Dim conn As SqlConnection = New SqlConnection(ConnectionString) ' Open the connection conn.Open() ' Create a DataTableMapping object Dim dtMapping As DataTableMapping = New DataTableMapping("Table", "Orders") Dim adapter As SqlDataAdapter = New SqlDataAdapter _ ("SELECT OrderID, ShipName, ShipCity, OrderDate FROM Orders", conn) ' Call DataAdapter's TableMappings.Add method adapter.TableMappings.Add(dtMapping) dtMapping.ColumnMappings.Add(New DataColumnMapping("OrderID", "mapID")) dtMapping.ColumnMappings.Add(New DataColumnMapping("ShipName", "mapName")) dtMapping.ColumnMappings.Add(New DataColumnMapping("ShipCity", "mapCity")) List of Listings

dtMapping.ColumnMappings.Add(New DataColumnMapping("OrderDate", "mapDate")) ADO.NET: Building Solutions ' Create Applied a DataSet Object and Data-Driven call DataAdapter's Fill method ISBN:1590590732 by Mahesh Chand and David Talbot ' Make sure you use new name od DataTableMapping i.e., MayOrders © 2003 (928 pages)DataSet() Dim ds AsApress DataSet = New This text provides extensive coverage of ADO.NET technology adapter.Fill(ds) including ADO.NET=internals, namespaces, classes, and DataGrid1.DataSource ds.DefaultViewManager interfaces, and takes a comprehensive look at XML 'Dispose namespaces and classes, and how to integrate both with conn.Close() ADO.NET. conn.Dispose() Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Figure 4-6 displays the results of Listing 4-33. Chapter 1 - ADO.NET Basics Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure 4-6: Column mapping

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16automatically - ASP.NET Server Controls and of Data The IDE generates much theBinding mappings, so you don't have to worry about them. But, Chapter 17 Building Real-World Web Applications occasionally, you may want to choose your own schema names for your DataSet that map back to the data Chapter source.18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Applied ADO.NET: Building CommandBuilder: Easing the Data-Driven Work of Solutions Programmers by Mahesh Chand and David Talbot

ISBN:1590590732

Sometimes creating SQL statements can be a lengthy job when dealing with many columns in a table. A Apress © 2003 (928 pages) CommandBuilder object reduces the burden of creating SQL statement for you. In other words, the This text provides extensive coverage of ADO.NET technology CommandBuilder object helps you generate UPDATE, DELETE, and INSERT commands on a single including ADO.NET internals, namespaces, classes, and interfaces, and takes The a comprehensive look at XML database table for a DataAdapter. OleDbCommandBuilder, SqlCommandBuilder, and namespaces and classes, and how to integrate both with OdbcCommandBuilder classes represent the CommandBuilder object in the OleDb, Sql, and Odbc ADO.NET. data providers (respectively).

Creating a CommandBuilder Object

Table of Contents


Creating a CommandBuilder object is pretty simple. You pass a DataAdapter as an argument of the Introduction CommandBuilder For example: Chapter 1 - ADO.NETcontructor. Basics Chapter 2


Chapter 3 - ADO.NET in Disconnected // Create a command builderEnvironments object Chapter SqlCommandBuilder 4 - ADO.NET in Connected builderEnvironments = new SqlCommandBuilder(adapter); Chapter 5


Chapter 6


- Data Binding and Windows FormsMembers Data-Bound Controls Using SqlCommandBuilder

Chapter 7 Chapter 8

- Constraints and Data Relations TheDataAdapter of Handling a CommandBuilder represents the DataProvider attached to a Chapter 9 - ADO.NETproperty Exception

CommandBuilder forODBC which.NET automatic SQL statements are generated. The GetDeleteCommand, Chapter 10 - Working object with the Data Provider GetUpdateCommand, and GetInsertCommand methods return the Delete,Update, and Insert Chapter 11 - Stored Procedures and Views commands in the form of a Command TheProviders RefreshSchema method refreshes the database Chapter 12 - Oracle, SQLXML, and Other object. .NET Data schema. Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Using SqlCommandBuilder


Now you'll how to use the SqlCommandBuilder in an application. You can use the Chapter 17 -see Building Real-World Web Applications OleDbCommandBuilder and OdbcCommandBuilder classes in the same way.



As usual, you create a connection to the database and use it to create the adapter object. The adapter is

Chapter 20 - COM ADO.NET constructed with Interoperability the initial queryand for the Employees table as well as with the database connection. Chapter 21 - Messaging

Next, you the and CommandBuilder by passing the DataAdapter into its constructor. The act of Chapter 22 construct - SQL Server ADO.NET: Notes on Performance creating Athe CommandBuilder causes the UPDATE,INSERT, and DELETE commands to Appendix - Relational Databases: automatically Some Basic Concepts be generated for the adapter. The following code creates two SqlCommandBuilder objects: Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Dim adapter As SqlDataAdapter = New SqlDataAdapter(SQL, conn) Index Dim builder1 As SqlCommandBuilder = New SqlCommandBuilder() List of Figures builder1.DataAdapter = adapter List of Tables Dim builder2 As SqlCommandBuilder = _ List of Listings New SqlCommandBuilder(adapter) List of Sidebars Next, fill the DataSet using the adapter and create an instance of the Employees DataTable from the DataSet: Dim ds As DataSet = New DataSet("EmployeeSet") adapter.Fill(ds, "Employees")

Now, insert a new DataRow into the DataTable in memory and populate a row with your desired values using the DataTable'sAddNew method. After that you call the DataRowCollection.Add method to

add the row to the DataTable:


ISBN:1590590732

' Create a data table object and add a new row Apress © 2003 (928 pages) Dim EmployeeTable As DataTable = ds.Tables("Employees") This text provides extensive coverage of ADO.NET technology Dim row As DataRow = EmployeeTable.NewRow() including ADO.NET internals, namespaces, classes, and row("FirstName") = takes "Rodney" interfaces, and a comprehensive look at XML row("LastName") namespaces= and "DangerField" classes, and how to integrate both with ADO.NET. row("Title") = "Manager " EmployeeTable.Rows.Add(row) Table of Contents Applied Data-Driven Solutions Finally,ADO.NET—Building you call DataAdapter's Update method to update the DataTable changes to the data source: Introduction Chapter 1

- ADO.NET Basics

Chapter 3


// Update data adapter Chapter 2 - Data Components in Visual Studio .NET adapter.Update(ds, "Employees"); Chapter 4

- ADO.NET in Connected Environments Listing 54-34 shows the full source code for creating and using a CommandBuilder object. Chapter - Handling ADO.NET Events Chapter 6


Listing 4-34: Creating and Using the SqlCommandBuilder Class - Data Binding and Windows Forms Data-Bound Controls

Chapter 7 Chapter 8

- Constraints and Data Relations As String = "Integrated Security=SSPI;" & _ ChapterDim 9 -ConnectionString ADO.NET Exception Handling

"Initial Source=MCB;" Chapter 10 - Working with Catalog=Northwind;Data the ODBC .NET Data Provider Dim conn As SqlConnection = New SqlConnection(ConnectionString) Chapter 11 - Stored Procedures and Views AsSQLXML, Stringand = Other "SELECT * FROM Employees" ChapterDim 12 -SQL Oracle, .NET Data Providers open a connection Chapter'13 - Developing a Custom Data Provider conn.Open() Dim adapter As SqlDataAdapter = New SqlDataAdapter(SQL, conn) Chapter 15 - Using ADO.NET in Xml Web Services Dim builder1 As SqlCommandBuilder = New SqlCommandBuilder() Chapter 16 - ASP.NET Server Controls and Data Binding builder1.DataAdapter = adapter Chapter 17 - Building Real-World Web Applications Dim builder2 As SqlCommandBuilder = _ Chapter 18 - Object-Relational Mapping in .NET New SqlCommandBuilder(adapter) Chapter'19 - Mapped Performance and Data Binding Create a Objects: command builderConsiderations object ChapterDim 20 -builder COM Interoperability and ADO.NET As SqlCommandBuilder = New SqlCommandBuilder(adapter) Chapter'21 - Messaging Create a dataset object ChapterDim 22 -ds SQLAs Server and ADO.NET: on Performance DataSet = NewNotes DataSet("EmployeeSet") Appendix A Relational Databases: Some Basic Concepts adapter.Fill(ds, "Employees") Appendix ' BCreate - Commonly a data Used table SQL Statements object and add a new row Dim DataTable Appendix C -EmployeeTable ADO.NET FrequentlyAs Asked Questions = ds.Tables("Employees") Index Dim row As DataRow = EmployeeTable.NewRow() row("FirstName") = "Bill" List of Figures row("LastName") = "Harvey" List of Tables row("Title") = "President" List of Listings EmployeeTable.Rows.Add(row) List of Sidebars ' Update data adapter adapter.Update(ds, "Employees") ' Dispose conn.Close() conn.Dispose() Chapter 14 - Developing Database Web Applications using ASP.NET

As you can see from Listing 4-34, you didn't have to figure out how to create InsertCommand for the Employees table because the CommandBuilder did it for you. All you had to do was add a row to the DataSet and invoke an Update on the DataAdapter. You may argue that the InsertCommand is automatically generated by VS .NET with the DataAdapter configurer, but the CommandBuilder works

with the SelectCommand you choose for the adapter, so you can change the SelectCommand on the fly Applied ADO.NET: and reuse the CommandBuilder atBuilding runtime. Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

Note that you should Apress call© the 2003RefreshSchema (928 pages) method of the CommandBuilder if the SelectCommand of the associatedThis DataAdapter RefreshSchema rebuilds the other command structures text provideschanges. extensiveThe coverage of ADO.NET technology including ADO.NET internals, namespaces, of classes, and (InsertCommand, DeleteCommand, UpdateCommand) the DataAdapter. interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions Staying within the Parameters by Mahesh Chand and David Talbot

ISBN:1590590732

ADO.NET wraps Apress a class©around parameters used for each column of the database. You can use the 2003 (928the pages) parameters in conjunction with SelectCommand to help you to select data for the DataSet. You also This text provides extensive coverage of ADO.NET technology use it in conjunction with the other commands of the CommandDataSet (InsertCommand, including ADO.NET internals, namespaces, classes, and interfaces, and takes atocomprehensive XML UpdateCommand, DeleteCommand) place data intolook theatDataSet. These are generated automatically and classes, component and how to integrate with when you insert anamespaces OleDbDataAdapter from the both Toolbox. ADO.NET.

TheOleDbType describes the type information for the parameter. It consists of everything from strings to Global Unique Identifiers (GUIDs). Table of Contents Applied ADO.NET—Building Solutions The Sql data provider hasData-Driven a SqlDbType, and the Odbc data provider has an OdbcType. These type Introduction names and definitions differ, depending upon the provider you're using; for example, the Money type is the Chapter - ADO.NET Basics same in1 Odbc and Sql data providers, but it's called Currency in OleDb data providers. Chapter 2

- Data Components in Visual Studio .NET Not only a parameter have a DbType property, but a parameter has a Direction (input, output), Chapter 3 does - ADO.NET in Disconnected Environments

Size, and a Value. Table 4-14 describes the SqlParameter properties. Chapter 4 - even ADO.NET in Connected Environments Chapter 5


Table 4-14: The SqlParameter Class Properties - Integrating XML with ADO.NET

Chapter 6

Chapter 7 - Data BindingDESCRIPTION and Windows Forms Data-Bound Controls PROPERTY Chapter 8

- Constraints and Data Relations DbType Represents the DbType of the parameter. Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider Direction Represents the direction of a parameter. A parameter can be input-only, Chapter 11 - Stored Procedures and Views output-only, bi-directional, or a stored procedure. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

IsNullable

Represents whether a parameter accepts null values.


Chapter 14 - Developing Database Web Applications using ASP.NET OleDbType Represents the OleDbType of the parameter. Chapter 15 - Using ADO.NET in Xml Web Services

Offset

Represents the offset to the Value property.


Chapter ParameterName 17 - Building Real-World Web the Applications Represents name of the parameter. Chapter 18 - Object-Relational Mapping in .NET

Precision

Represents the maximum number of digits used to represent the Value property.


Scale Chapter 21 - Messaging Represents the decimal places to which Value is resolved. Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Size

Represents the maximum size in bytes a column can store.


SourceColumn Represents the source column mapped to the DataSet. Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked SourceVersion Represents theQuestions DataRow version. Index ListSqlDbType of Figures

Represents the SqlDbType of the parameter

ListValue of Tables

Represents the value of the parameter.


Now you're going to see the construction of parameters using the Integrated Development Environment (IDE) as well as manually. Listing 4-35 shows the construction of an OleDbParameter generated by the IDE for the Northwind database. All commands have a collection of parameters; in this example, the parameter ContactName is being added to a command used for deleting from the database. Listing 4-35: Creating a Parameter Me.oleDbDeleteCommand2.Parameters.Add(New System.Data.OleDb.OleDbParameter("ContactName", System.Data.OleDb.OleDbType.Char, 30, System.Data.ParameterDirection.Input, False,

((System.Byte)(0)), ((System.Byte)(0)), Applied ADO.NET: Building Data-Driven Solutions "ContactName", System.Data.DataRowVersion.Original, ISBN:1590590732 by Mahesh Chand and David Talbot Nothing)) Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Luckily, the IDE automatically generates the parameters for you; as you can see, this is a lot of code to namespaces and classes, and how to integrate both with write for just one ADO.NET. parameter. Imagine if you had to manually deal with a database table of 50 parameters!

You need to create and add parameters to the command for each parameter reference that appears in the SQL command. If the SQL command only describes a single row insert or update, then you don't have Table of Contents parameters. But, more often than not,Solutions when you're using DataSets, DataTables, and DataRows, you'll Applied ADO.NET—Building Data-Driven need parameters because these in-memory structures operate on several rows. Introduction Chapter 1

- ADO.NET Basics

Chapter 3


Chapter 4


Parameters appear in a SQL Server INSERT command proceeded by an @ sign, as shown in the Chapter 2 - Data Components in Visual Studio .NET following code: sqlInsertCommand1.CommandText = - Handling ADO.NET Events @"INSERT INTO Customers(CustomerID, CompanyName, ContactName)"+ Chapter 6 - Integrating XML with ADO.NET " VALUES (@CustomerID, @CompanyName, @ContactName)" Chapter 7 - Data Binding and Windows Forms Data-Bound Controls In OleDb, parameters appear as question marks such as: Chapter 8 - Constraints and Data Relations oleDbInsertCommand2.CommandText = Chapter 9 -INTO ADO.NET Exception Handling "INSERT Customers(Address, City, CompanyName, ContactName)"+ Chapter 10 - Working ODBC .NET Data Provider " VALUES (?, ?,with ?,the ?)" Chapter 5


To add13 the- parameter to the InsertCommand of the SqlDataAdapter, simply call Add Chapter Developing @CustomerID a Custom Data Provider on the command's ParameterCollection. This willASP.NET return a parameter in which you can further assign Chapter 14 - Developing Database Web Applications using properties, Chapter 15 - such Usingas: ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

SqlParameter = Applications theSqlServerAdapter.InsertCommand. Chapter 17 - BuildingworkParam Real-World Web Parameters.Add("@CustomerID", SqlDbType.Int) Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Two other crucial properties are the name of the column that the parameter is mapping to and the

Chapter 21 - Messaging RowVersion. Typically, it's good to give the parameter the same name as the column of the database to Chapter 22 confusion: - SQL Server and ADO.NET: Notes on Performance avoid the Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

workParam.SourceColumn = "CustomerID" workParam.SourceVersion = DataRowVersion.Original

Appendix C - ADO.NET Frequently Asked Questions Index List of Figures

The can be either Current or Original. The SourceVersionproperty helps the List ofSourceVersion Tables DataAdapter's Update command decide which value version to load when executing the SQL List of Listings UpdateCommand on the database. (InsertCommand and DeleteCommand ignore the List of Sidebars SourceVersion.) The SourceVersion property comes in handy when you're updating a row whose primary key you may want to change. If the value is DataRowVersion.Original, then the primary key will retain its original value. You just saw an example of a parameter generated by the VS .NET IDE. It's always a better idea to write your own code if you really want to know what goes under the hood. So, let's create parameters and use them in a SqlCommand. The following code creates a parameter by reading a value from a TextBox control and deletes the record from the Categories table that matches the CategoryID as TextBox1.Text: dim strId as string = TextBox1.Text

dim sql = "DELETE Categories WHERE CategoryID=@catID" ADO.NET: Data-Driven Solutions dim cmd asApplied SqlCommand = Building new SqlCommand(sql, conn) ISBN:1590590732 by Mahesh Chand and David Talbot cmd.Parameters.Add("@catID", strId) Apress © 2003 (928 pages) cmd.ExecuteNonQuery() This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at returns XML As you can see, the Parameters property of SqlCommand an object of type SqlParameters, namespaces and classes, and how to integrate both with which representsADO.NET. a collection of parameters. It provides an Add method to add a parameter to the

collection.

Nowof let's construct a SqlCommand with an UPDATE SQL statement using three parameters. The following Table Contents code creates and adds three parameters to the collection. The code also constructs an UPDATE SQL Applied ADO.NET—Building Data-Driven Solutions statement with parameters and calls the ExecuteNonQuery method to execute the command:


- ADO.NET Basics

dim strId as Components string = inTextBox1.Text Chapter 2 - Data Visual Studio .NET dim strCatName as stringEnvironments = TextBox2.Text Chapter 3 - ADO.NET in Disconnected dim strDesc as string = TextBox3.Text Chapter 4 - ADO.NET in Connected Environments dim sql = "UPDATE Categories SET CategoryName=@catName, " & _ Chapter 5 - Handling ADO.NET Events " Description=@desc WHERE CategoryID=@catID" Chapter 6 - Integrating XML with ADO.NET dim cmd as SqlCommand = new SqlCommand(sql, conn) Chapter 7 - Data Binding and Windows Forms Data-Bound Controls cmd.Parameters.Add("@catID", strId) Chapter 8 - Constraints and Data Relations cmd.Parameters.Add("@catName", strCatName) Chapter 9 - ADO.NET Exception Handling cmd.Parameters.Add("@desc", strDesc) Chapter 10 - Working with the ODBC .NET Data Provider cmd.ExecuteNonQuery() Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

You can directly assign parameter values by using the Value property. For example, the following Chapter 13even - Developing a Custom Data Provider code adds parameters to theWeb command with the values NewCategory and New Description: Chapter 14 -two Developing Database Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter cmd.Parameters.Add("@CategoryName", 16 - ASP.NET Server Controls and Data Binding SqlDbType.VarChar, 80).Value = _

"NewCategory" Chapter 17 - Building Real-World Web Applications cmd.Parameters.Add("@Description", SqlDbType.Int).Value = _ Chapter 18 - Object-Relational Mapping in .NET "New Description" Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions The DataSet in Connected Environments by Mahesh Chand and David Talbot

ISBN:1590590732

In Chapter 3, you Apress saw how to create and use DataSet objects in disconnected environments. You saw © 2003 (928 pages) how to use a DataSet's properties and howcoverage to fill, delete, and update data using DataTable objects. In This text provides extensive of ADO.NET technology the following sections, you'll see how to work with DataSets in connected environments. Instead of using including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive lookdata at XML aDataTable, you'll use a DataAdapter to fill and save from a DataSet to a data source. namespaces and classes, and how to integrate both with ADO.NET. As mentioned, the Fill method of a DataAdapter fills data from a data source to a DataSet. Once the DataSet is filled with data, you can do any operation on this data. This data is disconnected data, and there's no connection between a DataSet and a data source until you finally call the Update method of a Table of Contents DataAdapter. The Update method of a DataAdapter saves the DataSet changes to the data Applied ADO.NET—Building Data-Driven Solutions source. You saw these Fill and Update methods in "The DataAdapter: Adapting to Your Environment." Introduction Chapter 1

- ADO.NET Basics

Chapter 3


Filling DataSet from Multiple Tables Chapter 2 -aData Components in Visual Studio .NET You saw how to fill a DataSet from a table in many of the previous samples. Now, there may be times - ADO.NET in Connected Environments when you'll want to view data from multiple tables in data-bound controls. If you remember ADO, you used Chapter 5 - Handling ADO.NET Events SQLJOIN statements to fill a recordset from multiple tables. Chapter 4 Chapter 6


Chapter 7 - Data Binding and Windows Data-Bound Controls In ADO.NET, there are different ways Forms you can fill data from multiple tables depending on your Chapter requirements. 8 - Constraints If you want andtoData viewRelations data from multiple tables in multiple data-bound controls, the simplest

way is create a DataAdapter for each table and fill a DataSet from a DataAdapter and use the Chapter 9 - ADO.NET Exception Handling DataSet bind data to the the ODBC controls. Listing 4-36 simply creates two SqlDataAdapter objects using Chapter 10 -toWorking with .NET Data Provider two different SqlCommand objects and then fills two different DataSet objects (which you later bind to Chapter 11 - Stored Procedures and Views two separate DataGrid controls). Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

Listing 4-36: Filling Data from Multiple Tables


Dim ConnectionString As String = Binding "Integrated Security=SSPI;" & _ Chapter 16 - ASP.NET Server Controls and Data "Initial Catalog=Northwind;Data Source=MCB;" Dim conn As SqlConnection = New SqlConnection(ConnectionString) Chapter 18 - Object-Relational Mapping in .NET conn.Open() Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Dim adapter1 As SqlDataAdapter = New SqlDataAdapter() Chapter 20 - COM Interoperability and ADO.NET Dim adapter2 As SqlDataAdapter = New SqlDataAdapter() Chapter 21 - Messaging adapter1.SelectCommand = New SqlCommand("SELECT * FROM Customers") Chapter 22 - SQL Server and ADO.NET: Notes on Performance adapter2.SelectCommand = New SqlCommand("SELECT * FROM Orders") Appendix A Relational Databases: Some Basic Concepts adapter1.SelectCommand.Connection = conn Appendix B - Commonly Used SQL Statements adapter2.SelectCommand.Connection = conn Appendix C -As ADO.NET Frequently Asked Questions Dim ds1 DataSet = New DataSet() Index Dim ds2 As DataSet = New DataSet() List adapter1.Fill(ds1) of Figures adapter2.Fill(ds2) List of Tables DataGrid1.DataSource = ds1.DefaultViewManager List of Listings DataGrid2.DataSource = ds2.DefaultViewManager List of Sidebars ' Dispose conn.Close() conn.Dispose() Chapter 17 - Building Real-World Web Applications

Now what if you want to fill a DataSet with data from multiple tables? Actually, that's pretty easy, too. If you remember the Merge method of the DataSet from Chapter 3, you'll learned how to merge two DataSet objects. You can use the same method to fill data from two different tables in two different DataSet objects and later call the Merge method, which merges one DataSet into another. Listing 4-37 fills two DataSet objects from two different tables—Customers and Orders—and later one DataSet merges into another. After that you just bind the final DataSet to a DataGrid control, which displays

data from both tables.


by Mahesh and David Talbot Listing 4-37: Merging TwoChand DataSet Objects

ISBN:1590590732

Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology Dim adapter As SqlDataAdapter = New SqlDataAdapter() including ADO.NET internals, namespaces, classes, and adapter.SelectCommand SqlCommand("SELECT * FROM Customers") interfaces, and takes= a New comprehensive look at XML adapter.SelectCommand.Connection conn both with namespaces and classes, and how to= integrate ADO.NET. Dim ds1 As DataSet = New DataSet() adapter.Fill(ds1) adapter.SelectCommand = New SqlCommand("SELECT * FROM Orders") Table of Contents adapter.SelectCommand.Connection = conn Applied ADO.NET—Building Data-Driven Solutions Dim ds2 As DataSet = New DataSet() Introduction adapter.Fill(ds2) Chapterds1.Merge(ds2, 1 - ADO.NET BasicsFalse, MissingSchemaAction.Add) Chapter 2 - Data Components = in ds1.DefaultViewManager Visual Studio .NET DataGrid1.DataSource Chapter 3


Chapter 4


Chapter 5

- Handling ADO.NET Events Note Merge method hasADO.NET seven overloaded forms. Using this method, you can even merge Chapter 6 The - Integrating XML with

and DataTable with a DataSet. Chapter 7 DataRow - Data Binding and Windows objects Forms Data-Bound Controls Chapter 8


- ADO.NET Exception Handling Using a SQL Statement to Read Data from Two or More Tables

Chapter 9


Using a11SQL statement is the and simplest Chapter - Stored Procedures Viewsway to put data from multiple tables into a DataSet. The following code selects data from the Customers and Data Orders tables and fills it to a single DataSet: Chapter 12 - Oracle, SQLXML, and Other .NET Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web=Applications using ASP.NET Dim conn As SqlConnection New SqlConnection(ConnectionString) Chapter SQL =15"SELECT - Using ADO.NET * FROMin Customers; Xml Web Services SELECT * FROM Orders"

conn.Open() Chapter 16 - ASP.NET Server Controls and Data Binding Dim adapter As Real-World SqlDataAdapter = New SqlDataAdapter(SQL, conn) Chapter 17 - Building Web Applications Dim ds DataSet = New DataSet("CustOrdersDataSet") Chapter 18 As - Object-Relational Mapping in .NET adapter.Fill(ds) Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

Adding, Updating, and Deleting Data through the DataSet


You add,B edit, and delete data a DataSet through DataSet objects. As you know, a DataSet is a Appendix - Commonly Used SQLinStatements

collection of DataSet objects. The DataSet'sRows and Columns properties represent the collection of aDataSet's rows and columns, which are represented by the DataRowCollection and Index DataColumnCollection objects. The DataRowCollection and DataColumnCollection classes List of Figures provide methods to add and delete rows and columns, respectively (see Chapter 3 for more details). You List of Tables can add a new row to a DataTable using its NewRow method, which takes a DataRow as an argument. List of Listings To update a DataRow's data (through DataTable), you first get a DataRow based on the index of the List Sidebars rowofand edit its values. The Delete method of a DataRow deletes a row. Listing 4-38 adds, updates, and deletes data of a DataSet through a DataTable and a DataRow. Appendix C - ADO.NET Frequently Asked Questions

Listing 4-38: Adding, Editing, and Deleting a DataSet Rows Dim adapter As SqlDataAdapter = New SqlDataAdapter(SQL, conn) ' Create a command builder object Dim builder As SqlCommandBuilder = New SqlCommandBuilder(adapter) ' Create a dataset object Dim ds As DataSet = New DataSet() adapter.Fill(ds, "Employees") ' Create a data table object and add a new row

Dim EmployeeTable As DataTable = ds.Tables("Employees") Applied ADO.NET: Building Data-Driven Solutions Dim row As DataRow = EmployeeTable.NewRow() ISBN:1590590732 by Mahesh Chand and row("FirstName") = "New David Name"Talbot Apress © 2003 (928 pages) row("LastName") = "Mr. Last" This text extensive coverage of ADO.NET technology row("Title") = provides "New Employee" including ADO.NET internals, namespaces, classes, and EmployeeTable.AcceptChanges() interfaces, and takes a comprehensive look at XML EmployeeTable.Rows.Add(row) namespaces and classes, and how to integrate both with ' Get theADO.NET. last row Dim editedRow As DataRow = EmployeeTable.Rows _ (EmployeeTable.Rows.Count - 1) Table of Contents editedRow("FirstName") = "Edited Name" AppliededitedRow("LastName") ADO.NET—Building Data-Driven=Solutions "Mr. Edited" Introduction editedRow("Title") = "Edited Employee" ChapterEmployeeTable.AcceptChanges() 1 - ADO.NET Basics Chapter'2 Delete - Data Components a row. Last in Visual rowStudio - 1 .NET As DataRow = EmployeeTable.Rows _ ChapterDim 3 -deletedRow ADO.NET in Disconnected Environments - 2) Chapter(EmployeeTable.Rows.Count 4 - ADO.NET in Connected Environments ChapterdeletedRow.Delete() 5 - Handling ADO.NET Events ChapterEmployeeTable.AcceptChanges() 6 - Integrating XML with ADO.NET changes toWindows the database Chapter'7 Save - Data Binding and Forms Data-Bound Controls adapter.Update(ds, "Employees") Chapter 8 - Constraints and Data Relations Chapter 9



Accepting and Rejecting Changes through the DataSet


TheDataSet class provides methods that allow you to make sure if you want to save changes or reject changes made to a DataSet since it was loaded or the last time AcceptChanges was called. The Chapter 15 - Using ADO.NET in Xml Web Services AcceptChanges method saves the changes, and the RejectChanges method rejects (rolls back) all Chapter 16 - ASP.NET Server Controls and Data Binding the changes made to the DataSet.Listing 4-39 shows you how to use these methods to accept and Chapter 17 - Building Real-World Web Applications reject changes. Chapter 14 - Developing Database Web Applications using ASP.NET


Chapter - Mapped Performance Considerations and Data Binding Listing19 4-39: UsingObjects: the AcceptChanges and RejectChanges Methods of a DataSet Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

Dim adapter As SqlDataAdapter = New SqlDataAdapter(SQL, conn) ' Create a command builder object Appendix A -builder Relational Databases: Some Basic Concepts Dim As SqlCommandBuilder = New SqlCommandBuilder(adapter) Appendix - Commonly Used SQL object Statements ' BCreate a dataset Appendix C -ds ADO.NET Frequently=Asked Dim As DataSet New Questions DataSet() Index adapter.Fill(ds, "Employees") List of Figures ' Create a data table object and add a new row List of Tables Dim EmployeeTable As DataTable = ds.Tables("Employees") Dim row As DataRow = EmployeeTable.NewRow() List of Listings row("FirstName") = "New Name" List of Sidebars row("LastName") = "Mr. Last" row("Title") = "New Employee" EmployeeTable.Rows.Add(row) ' Update data adapter If MessageBox.Show("Do you want to save change?", _ "DataSet AcceptReject Methods", _ MessageBoxButtons.YesNo, MessageBoxIcon.Question) _ = DialogResult.Yes Then ds.AcceptChanges() Else ds.RejectChanges() Chapter 22 - SQL Server and ADO.NET: Notes on Performance

End If Applied ADO.NET: Building Data-Driven Solutions adapter.Update(ds, "Employees") by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with As you know, youADO.NET. fill a DataSet using the Fill method of a DataAdapter, modify its contents, and call

Saving Changed Data Only

theUpdate method to save changes made to a DataSet. This method sends the entire DataSet data backoftoContents the database. This scenario may affect the performance and increase network congestion when Table working with large data—especially over the Web. Applied ADO.NET—Building Data-Driven Solutions Introduction Wouldn't it be nice if you could send only the changed data of a DataSet back to the database instead of Chapter - ADO.NET Basics of a DataSet? The DataSet provides methods that allow you to find out the sending1 the entire contents Chapter 2 rows - Data Components in Visualrows Studio .NET changed and retrieve changed only. The HasChanges method of the DataSet returns True if Chapter ADO.NETbased in Disconnected Environments it finds 3any- changes on the DataRow's state, represented by the DataRowState enumeration. The Chapter GetChanges 4 - ADO.NET methodinreturns Connected the Environments changed rows since a DataSet was loaded or AcceptChanges was

last called returns the changed Chapter 5 -and Handling ADO.NET Eventsdata in a DataSet. Now you just need to call the DataAdapter's Update with the DataSet object returned by the GetChanges method, which will send this Chapter 6 method - Integrating XML with ADO.NET DataSet's contents back to Windows the database. Chapter 7 - Data Binding and Forms Data-Bound Controls Chapter 8


Listing 4-40 shows you how to call the GetChanges method and save only the modified rows back to the - ADO.NET Exception Handling database.

Chapter 9


Chapter - Stored Procedures and Views Listing11 4-40: Saving Only Modified Rows of a DataSet Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

' See if DataSet has changes or not If Not ds.HasChanges(DataRowState.Modified) Then Exit Sub ChapterDim 15 -tmpDtSet Using ADO.NET Xml Web Services As inDataSet Chapter'16 ASP.NET Server Controls and Data Binding GetChanges for modified rows only. ChaptertmpDtSet 17 - Building Real-World Web Applications = ds.GetChanges(DataRowState.Modified) ChapterIf 18 tmpDtSet.HasErrors - Object-Relational MappingThen in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding MessageBox.Show("DataSet has errors") Chapter 20 Exit - COMSub Interoperability and ADO.NET ChapterEnd 21 -If Messaging Chapteradapter.Update(tmpDtSet) 22 - SQL Server and ADO.NET: Notes on Performance Chapter 14 - Developing Database Web Applications using ASP.NET


Using a DataSet vs. Using a DataReader

Index

List of Figures

When should you use a DataSet and when should you use a DataReader? This question comes up on List of Tables almost every ADO.NET-related discussion forum or news-group. There are several differences between List of Listings theoftwo: List Sidebars Accessing performance: A DataReader provides a read-only, forward-only view of data and is faster than a DataSet because it's only reading data. In other words, you can only read data using a DataReader. A DataSet provides both read and write access to data. Data-bound connectivity: A DataReader doesn't provide any direct data-bound connectivity, which makes it less flexible than a DataSet. A DataSet is a versatile and flexible control, which allows both data read and write options and provides way to add, edit, delete, and view data in data-bound controls with little effort. Connected state: A DataReader is always in a connected state. This means if you're using a

DataReader, there's always a connection established between the reader and the database, until ADO.NET: Building stores Data-Driven you close theApplied DataReader. A DataSet data in Solutions a disconnected state in Extensible Markup ISBN:1590590732 by Mahesh Chand and David Talbot Language (XML) format. Once you fill data from a data source to a DataSet, there's no connection Apress © 2003 (928 pages) between a DataSet and the database. A connection is established when you read or updated data This text provides extensive coverage of ADO.NET technology again. including ADO.NET internals, namespaces, classes, and

interfaces, andoftakes comprehensive look at XML You should now have an idea whena to use a DataReader and when to use a DataSet. namespaces and classes, and how to integrate both with ADO.NET.

Fetching Data Based on Wildcard Characters Table of Contents TheSELECT...LIKE SQL statement is useful when you want to select rows based on a wildcard string. Applied ADO.NET—Building Data-Driven Solutions For example, say you want to get all rows of the Employees table where an employee's first name starts Introduction with C and ends with a. You build a SQL statement like so: Chapter 1 - ADO.NET Basics Chapter 2 -as Data Components in Visual*Studio Dim sql string = SELECT FROM.NET Employees WHERE FirstName LIKE 'C%a' Chapter 3 - ADO.NET in Disconnected Environments Chapter 4

- ADO.NET in Connected Environments Another5 useful example of LIKE is when you want to select all the employees whose first name contains Chapter - Handling ADO.NET Events

the string You can XML buildwith a SELECT statement as follows: Chapter 6 gar. - Integrating ADO.NET Chapter 7


Chapter Dim sql 8 -as Constraints stringand = Data SELECT Relations * FROM Employees WHERE FirstName LIKE '%gar%' Chapter 9



Now you can use this SELECT statement in a DataReader or DataAdapter to retrieve the data from a database.




Applied Building Data-Driven Solutions The DataView in ADO.NET: Connected Environments by Mahesh Chand and David Talbot

ISBN:1590590732

In Chapter 3, you Apress learned© 2003 how (928 a DataView is useful to sort, filter, and view data based on different selection pages) criteria. You also This saw text howprovides to add, edit, and delete data a DataView. extensive coverage of from ADO.NET technologyIn Chapter 3, you saw all of this in disconnected data. Also, you created DataView objects from DataTable objects. In the following sections, including ADO.NET internals, namespaces, classes, and and takes a objects comprehensive look at XML you'll see how to interfaces, work with DataView in a connected environment. You'll also learn how to search and namespaces and classes, and different how to integrate with data. sort data based on criteria and how to create views ofboth the same ADO.NET.

You simply create a DataView from a DataTable, which can be retrieved using the Tables property of a DataSet. The following code creates a DataView from the first table of a DataSet and binds a DataView to Table of Contents theDataGrid control: Applied ADO.NET—Building Data-Driven Solutions Introduction

Dim dtView1 As DataView = New DataView(ds.Tables(0)) Chapter 1 - ADO.NET Basics DataGrid1.DataSource = dtView1 - Data Components in Visual Studio .NET

Chapter 2 Chapter 3


Chapter 4


Chapter 5


Creating Multiple - Integrating XML Views with ADO.NET

Chapter 6 Chapter 7


The main features of a DataView is that it's easily bound to controls, and it provides filter and sort properties, Chapter 8 - Constraints and Data Relations which allow you to create different views of the same data. To see how to use DataViews, let's create a Chapter 9 - ADO.NET Exception Handling Windows application. After creating a Windows application, you'll add two DataGrid controls, four TextBox Chapter 10 - Working with the ODBC .NET Data Provider controls, two CheckBox controls, and a Button control and arrange them as shown in Figure 4-7. The Load Chapter 11 - Stored Procedures and Views Data button loads data from the Northwind SQL Server database's Orders table. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions IndexFigure 4-7: Default multiple views application List of Figures

Now, if you enter the filter and sort criteria from both DataGrid controls, the data is filtered and sorted based List of Tables on of theListings criteria. For example, Figure 4-8 shows the criteria and the result of clicking the Load Data button. List List of Sidebars


ISBN:1590590732


Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1 - 4-8: ADO.NET Basics Figure Multiple views with different filter and sorting criteria Chapter 2 - Data Components in Visual Studio .NET Chapter 3


Chapter 4


Now let's examine the code. Listing 4-41 shows the private members.

Chapter - Handling Events Listing54-41: PrivateADO.NET Members Chapter 6


Chapter 7


Private ConnectionString As String = "Integrated Security=SSPI;" & _ Chapter 8 - Constraints and Data Relations "Initial Catalog=Northwind;Data Source=MCB;" Chapter 9 - ADO.NET Exception Handling Private conn As SqlConnection Chapter 10 - Working with the ODBC .NET Data Provider Private SQL As String = _ Chapter 11 - Stored Procedures and Views "SELECT EmployeeID, CustomerID, ShipCity, ShipName FROM Orders" Chapter 12 Oracle, SQLXML, and Other .NET Data Providers Private adapter As SqlDataAdapter Chapter a Custom Data Provider Dim13ds- Developing As DataSet = New DataSet() Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Listing 17 4-42 shows the code of Web the Load Data button's click event handler. As you can see, the code creates two Chapter - Building Real-World Applications different DataView objects from the DataSet and sets their RowFilter and Sort properties based on the Chapter 18 - Object-Relational Mapping in .NET data entered on theObjects: form. In Performance the end, youConsiderations bind each DataView to a separate DataGrid control. Chapter 19 - Mapped and Dataobject Binding Chapter 20 - COM Interoperability and ADO.NET

Listing 4-42: The Load Data Button's Click Event Handler



Private LoadDataBtn_Click(ByVal sender As System.Object, _ Appendix A -Sub Relational Databases: Some Basic Concepts ByVal e As System.EventArgs) Handles LoadDataBtn.Click conn = New SqlConnection(ConnectionString) Appendix C - ADO.NET Frequently Asked Questions Try Index conn.Open() List of Figures adapter = New SqlDataAdapter(SQL, conn) List of Tables adapter.Fill(ds) List of Listings Catch exp As SqlException List of Sidebars exp.Message.ToString() End Try Appendix B - Commonly Used SQL Statements

' Create two DataView objects Dim dtView1 As DataView = New DataView(ds.Tables(0)) Dim dtView2 As DataView = New DataView(ds.Tables(0)) ' Set RowFilter and Sort proeprties of DataView1 If (TextBox1.Text String.Empty) Then dtView1.RowFilter = TextBox1.Text End If Dim sortStr1 As String = TextBox2.Text If (sortStr1 String.Empty) Then

If CheckBox1.Checked Then Applied ADO.NET: +Building Data-Driven Solutions sortStr1 = sortStr1 " DESC" ISBN:1590590732 by Mahesh Chand and David Talbot Else Apress © 2003 (928 pages) sortStr1 = sortStr1 + " ASC" End If This text provides extensive coverage of ADO.NET technology including internals, namespaces, classes, and dtView1.Sort = ADO.NET sortStr1 interfaces, and takes a comprehensive look at XML End If namespaces and classes, and how to integrate both with ADO.NET.

' Set RowFilter and Sort proeprties of DataView2 If (TextBox3.Text String.Empty) Then Table ofdtView2.RowFilter Contents = TextBox3.Text Applied ADO.NET—Building Data-Driven Solutions End If Introduction Dim sortStr2 As String = TextBox4.Text Chapter 1 - ADO.NET Basics If (sortStr2 String.Empty) Then ChapterIf 2 CheckBox2.Checked - Data Components in Visual Then Studio .NET " DESC" Chapter 3 sortStr2 - ADO.NET = in sortStr2 Disconnected+Environments ChapterElse 4 - ADO.NET in Connected Environments = sortStr2 Chapter 5 sortStr2 - Handling ADO.NET Events+ " ASC" ChapterEnd 6 -If Integrating XML with ADO.NET sortStr2 ChapterdtView2.Sort 7 - Data Binding=and Windows Forms Data-Bound Controls End If Chapter 8 - Constraints and Data Relations Chapter 9


' Bind both DataViews to two different DataGrids DataGrid1.DataSource = dtView1 Chapter 11 - Stored Procedures and Views DataGrid2.DataSource = dtView2 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers ' release objects Chapter 13 - Developing a Custom Data Provider conn.Close() Chapter 14 - Developing Database Web Applications using ASP.NET conn.Dispose() Chapter 15 - Using ADO.NET in Xml Web Services End Sub Chapter 10 - Working with the ODBC .NET Data Provider

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Transactions and Concurrency in ADO.NET Chapter 20 - COM Interoperability and ADO.NET

Transactions are groups of database commands that execute as a package and provide an ability to Chapter 21 - Messaging

commit or roll back (abort) all changes made during the transaction processing. Transaction changes will be committed if there wasn't an error during the transaction processing. If an error occurs during the Appendix A - Relational Databases: Some Basic Concepts transaction processing, all changes will be aborted and data will be same as it was before any transactions Appendix B - Commonly Used SQL Statements started. To start transaction processing, you call BeginTransaction. At the end you can call Appendix C - ADO.NET Frequently Asked Questions CommitTransaction or Rollback Transaction based on the status of the transactions. IndexCommitTransaction reflects all changes to the database, and Rollback aborts all changes. Chapter 22 - SQL Server and ADO.NET: Notes on Performance

List of Figures List ofFor Tables example, say you have an application with two tables: Inventory and Orders. When a customer places

order, the Inventory table needs to be reduced. Now imagine that updating the Orders table was List ofan Listings List ofsuccessful, Sidebars but updating the Inventory table failed. This scenario leads to data inconsistency. To maintain

the integrity of data, you could package both commands into a single transaction. If one table updated successfully and the other table didn't, the transaction could be rolled back; otherwise, the transaction could be committed. Nested transactions are transactions within the scope an existing transaction. The changes made within the nested transactions are invisible to the top-level transactions until the nested transactions are committed. To create nested transactions, you call BeginTransaction with CommitTransaction and RollbackTransaction within the existing transactions. For example: Begin Transaction A Begin Transaction B

Do something Applied ADO.NET: Building Data-Driven Solutions Commit Transaction B ISBN:1590590732 by Mahesh Chand and David Talbot Commit Transaction A Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including internals, namespaces, classes, and Savepoints are useful ADO.NET when you're working with nested transactions. There are occasions when you want to interfaces, and takes comprehensive look at XML abort a portion of transaction, but anot all of it. For example, say you're processing four commands as nested namespaces and classes, and how to integrate both with transactions, ADO.NET. but you want to commit only two commands and abort two of them. A savepoint is a temporary point in the transaction that you want to save (or back up) without aborting the entire transaction. In transaction processing, you set the savepoint call and come back later when you think it's safe to process Table the of Contents transaction. A unique number represents the savepoint. For example: Applied ADO.NET—Building Data-Driven Solutions Introduction Begin Transaction A Chapter 1 -Do ADO.NET Basics something Chapter 2

- Data SetSavePoint Components in Visual Studio .NET

Chapter 3

- ADO.NET Do something in Disconnected Environments

Commit or Rollback Transaction Chapter 4 - ADO.NET in Connected EnvironmentsA Chapter 5


Chapter 6


Chapter 7


Managing and writing reliable and scalable multitier distributed applications is one of the most challenging Chapter 8 - Constraints and Data Relations jobs for database developers. Think about multiple clients accessing same server database Chapter 9 - ADO.NET Exception Handling simultaneously-some of them are accessing data, some of them are updating the same data, and some of Chapter 10 - Working with the ODBC .NET Data Provider them are trying to delete the same data that other clients are using in their operations. Chapter 11 - Stored Procedures and Views

Chapter To 12 prevent - Oracle, dataSQLXML, inconsistency, and Other it's .NET important Data Providers to provide some kind of mechanism so other users can't

update when a user is already using that data. The mechanism to deal with this situation is called Chapter 13 - data Developing Custom Data Provider concurrency control. Concurrency is the method which multiple clients can access and update the same Chapter 14 - Developing Database Web Applications usingbyASP.NET data without concerned that they're forcing data redundancy and inconsistency. Chapter 15simultaneously - Using ADO.NET in Xmlbeing Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

There are three common ways to manage concurrency:


Pessimistic concurrency control: In pessimistic concurrency, the data is unavailable to other users from the time the record is fetched by a user until it's updated in the database. This is useful when Chapter 20users - COM Interoperability andgoing ADO.NET accessing a row are to play a major role based on the data they're accessing. Another Chapter 21advantage - Messaging of pessimistic concurrency is less locking overhead. Once a row is locked, it's locked until Chapter 22the - SQL ADO.NET: Notes on Performance first Server user is and done. The main drawback of this type of concurrency is that data is not available to Appendix Aother - Relational Databases: Some Basic Concepts data left his terminal, other users have to wait for him to users. For example, if a user accessing Appendix Brelease - Commonly Used SQL Statements the connection. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding


Optimistic concurrency control: In optimistic concurrency, data is available all the time except when a user is updating the data. The update examines the row in the database and determines whether any List of Tables changes have been made. In this type of concurrency, the locks are set and held only while the List of Listings database is being accessed. The locks prevent other users from attempting to update records at the List of Sidebars same instant. If other users try to update the data that is locked by first user, the update fails. List of Figures

Last in wins concurrency control: In this case of concurrency control, a row is unavailable to other users only while the data is being updated. This is only useful when the last user's update counts. For example, it's useful if you're keeping track of the last winner of a race. In other words, many users are updating the same data, and the person who updates it last is the latest data. The data updated by other users will be lost. In this case, data could easily lead to inconsistencies because of network slowness when data previously posted arrives last.

Note SeeAppendix A for more on locking, cursors, and isolation levels.

Applied ADO.NET: Building Data-Driven Solutions Using Transactions in ADO.NET by Mahesh Chand and David Talbot

ISBN:1590590732

ADO.NET provides Apress a Transaction © 2003 (928 pages) class that represents a transaction. All data providers provide their own version of the Transaction class. In the provider classes, a transaction is represented as an object returned This text provides extensive coverage of ADO.NET technology including ADO.NET namespaces,You classes, and after BeginTransaction is calledinternals, on a Connection. can commit (make permanent) or roll back interfaces, and takes a comprehensive look at XML (cancel and return to the original state) the transactions. Table 4-15 describes the methods for the OleDb namespaces and classes, and how to integrate both with provider'sTransaction class. ADO.NET. Table 4-15: Methods of the Transaction Class Table of Contents

METHOD

DESCRIPTION

Applied ADO.NET—Building Data-Driven Solutions Introduction Commit Chapter 1

Commits the transaction to the database

- ADO.NET Basics

Rollback Rolls back.NET a transaction to the previous database state - Data Components in Visual Studio Chapter 3 - ADO.NET in Disconnected Environments Begin(IsolationLevel) Begins a nested database transaction passing the isolation level Chapter 2 Chapter 4


Chapter 5 - Handling ADO.NET TheIsolationLevel allowsEvents you to lock your transaction in various ways. The default isolation level is Chapter ReadCommitted, 6 - Integrating which XML allows with ADO.NET you to alter data during a transaction. If you use an isolation level of

RepeatableRead, locks areWindows placed Forms on all the data, so Controls you can't alter the data in this transaction. If you lock at Chapter 7 - Data Binding and Data-Bound theSerializable level, placed on the entire DataSet, preventing changes to all the data in the Chapter 8 - Constraints andlocks Data are Relations DataSet. 4-16Exception describesHandling different isolation levels. Chapter 9 -Table ADO.NET Chapter 10 - Working with the ODBC .NET Data Provider

Table 4-16: Isolation Levels and Available Chapter 11 - Stored Procedures Views for Transactions Chapter 12 - Oracle, SQLXML, DESCRIPTION and Other .NET Data Providers ISOLATION LEVEL Chapter 13 - Developing a Custom Data Provider

ReadCommitted Locks areApplications shared to prevent inconsistent reads between multiple users. Chapter 14 - Developing Database Web using ASP.NET (default) altered during the transaction. Chapter 15 - Using ADO.NET inData Xml can Webbe Services Chapter 16 - ASP.NET Server Controls and Data Binding ReadUncommitted Locks are not placed on the data, so a dirty read is possible. A dirty read Chapter 17 - Building Real-World Web Applications occurs when a transaction reads some data that has been added to the Chapter 18 - Object-Relationaltable Mapping but in not.NET committed yet. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

RepeatableRead

Locks are placed on all the data of the database query, so the data can't be altered during a read.


Chapter Chaos 22 - SQL Server and ADO.NET: Notes on Performance The changes made on transactions awaiting commitment can't be altered. Appendix A - Relational Databases: Some Basic Concepts

Serializable

A range lock is placed on an entire DataSet, preventing changes from being made to the DataSet



Unspecified Index

TheIsolationLevel can't be determined.


Using Concurrency in ADO.NET

List of Listings

List of Sidebars

The ADO.NET model assumes that optimistic concurrency is the default concurrency model because of the disconnected nature of data in ADO.NET. A user reads data in a DataSet through a DataAdapter, and data is available to a user as a local copy of the data. The server database is available to all other users. Even though the ADO.NET model supports optimistic concurrency by default, that doesn't mean you can't implement pessimistic concurrency in ADO.NET. The following two examples show you how to handle both cases. Listing 4-43 shows you how to implement optimistic concurrency. You can handle the optimistic concurrency by creating an Update command that checks the database to make sure the original data of the database row hasn't changed when an immediate Update is about to be performed. It does this by creating two sets of parameters for the Update command: a current set of parameters and an original set of parameters. The

original parameters maintain the data that was originally read in from the DataSet. If the data has changed in Applied Building Data-Driven Solutions the data source, when youADO.NET: run the Update command with the WHERE clause filter, the filter won't find the row by Mahesh Chand and David Talbot and an Update won't occur. If the data has not changed in theISBN:1590590732 data source, then the WHERE clause will find the Apress © 2003and (928the pages) original row you're updating, row will be updated with the new data. Listing 4-43 has a built-in WHERE This text provides extensive coverage of ADO.NET technology clause on the original data. The IDE generates parameters such as @ShipCity and @ShipDate. The including ADO.NET internals, namespaces, classes, and framework even generates the Update command (which has been shortened in the example). interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Listing 4-43: Optimistic ADO.NET.Concurrency

Private Sub TestOptimisticConcurrency() Dim ConnectionString As String = "Integrated Security=SSPI;" & _ Applied ADO.NET—Building Data-Driven Solutions "Initial Catalog=Northwind;Data Source=MCB;" Introduction Dim conn As SqlConnection = New SqlConnection(ConnectionString) Chapterconn.Open() 1 - ADO.NET Basics ChapterTry 2 - Data Components in Visual Studio .NET Chapter 3 Dim - ADO.NET Disconnected Environments da As inSqlDataAdapter = New SqlDataAdapter("SELECT * FROM Orders", Chapter 4 Dim - ADO.NET Connected=Environments ds As inDataSet New DataSet("test") Chapter 5 Dim - Handling ADO.NET updateCmd AsEvents SqlCommand = New SqlCommand() Chapter 6 updateCmd.CommandText - Integrating XML with ADO.NET = "UPDATE Orders SET CustomerID = @CustomerID," @OrderDate, = @ShippedDate WHERE " & _ Chapter 7 "OrderDate - Data Binding=and Windows FormsShippedDate Data-Bound Controls "(OrderID = @Original_OrderID) AND (CustomerID = @Original_CustomerID Chapter 8 - Constraints and Data Relations "OR @Original_CustomerID IS NULL AND CustomerID IS NULL) AND " & _ Chapter 9 - ADO.NET Exception Handling "(OrderDate = @Original_OrderDate OR @Original_OrderDate " & _ Chapter 10 - Working with the ODBC .NET Data Provider "IS NULL AND OrderDate IS NULL) AND (ShippedDate = " & _ Chapter 11 - Stored Procedures and Views "@Original_ShippedDate OR @Original_ShippedDate IS NULL AND " & _ Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers "ShippedDate IS NULL); SELECT CustomerID, OrderDate, ShippedDate, " & Chapter 13 - Developing a Custom Data Provider "OrderID FROM Orders WHERE (OrderID = @OrderID)"

Table of Contents


updateCmd.Connection = conn ' CustomerID parameter Chapter 17 - Building Real-World Web Applications SqlParameter _ updateCmd.Parameters.Add(New Chapter 18 - Object-Relational MappingSqlDbType.NVarChar, in .NET ("@CustomerID", 5, "CustomerID")) Chapter 19 Mapped Objects: Performance Considerations and Data Binding ' -OrderDate parameter Chapter 20 - COM Interoperability and ADO.NET updateCmd.Parameters.Add(New SqlParameter _ Chapter 21 - Messaging ("@OrderDate", SqlDbType.DateTime, 8, "OrderDate")) Chapter 22 ' -ShippedDate SQL Server and ADO.NET: parameter Notes on Performance updateCmd.Parameters.Add(New SqlParameter _ Appendix A - Relational Databases: Some Basic Concepts ("@ShippedDate", SqlDbType.DateTime, 8, "ShippedDate")) Appendix B - Commonly Used SQL Statements updateCmd.Parameters.Add(New SqlParameter _ Appendix C - ADO.NET Frequently Asked Questions ("@Original_OrderID", SqlDbType.Int, 4, _ Index ParameterDirection.Input, False, _ List of Figures (CType((0), System.Byte)), (CType((0), System.Byte)), _ List of Tables "OrderID", DataRowVersion.Original, Nothing)) List of Listings updateCmd.Parameters.Add(New SqlParameter _ List of Sidebars ("@Original_CustomerID", SqlDbType.NVarChar, _ 5, ParameterDirection.Input, False, (CType((0), System.Byte)), _ (CType((0), System.Byte)), "CustomerID", _ DataRowVersion.Original, Nothing)) updateCmd.Parameters.Add(New SqlParameter _ ("@Original_OrderDate", SqlDbType.DateTime, _ 8, ParameterDirection.Input, False, (CType((0), System.Byte)), _ (CType((0), System.Byte)), "OrderDate", DataRowVersion.Original, Nothing)) updateCmd.Parameters.Add(New SqlParameter _ ("@Original_ShippedDate", SqlDbType.DateTime, _ 8, ParameterDirection.Input, False, (CType((0), System.Byte)), _ Chapter 16 - ASP.NET Server Controls and Data Binding

conn)

& _ " & _

_

(CType((0), System.Byte)), "ShippedDate", _ Applied ADO.NET: Building Data-Driven DataRowVersion.Original, Nothing))Solutions ISBN:1590590732 by Mahesh Chand and David Talbot updateCmd.Parameters.Add(New SqlParameter("@OrderID", _ Apress © 2003 (928 pages) SqlDbType.Int, 4, "OrderID")) This text provides coverage of ADO.NET technology da.UpdateCommand = extensive updateCmd including ADO.NET internals, namespaces, classes, and da.Fill(ds, "Orders") interfaces, and takes a comprehensive look at XML ' update the row the and dataset namespaces andin classes, how to integrate both with ds.Tables("Orders").Rows(0).BeginEdit() ADO.NET. ds.Tables("Orders").Rows(0)("OrderDate") = DateTime.Now ds.Tables("Orders").Rows(0)("ShipCity") = "Leone" Table of Contents ds.Tables("Orders").Rows(0).EndEdit() Applied ADO.NET—Building Solutions ' update the Data-Driven row in the data Source (Orders Table) Introduction da.Update(ds, "Orders") Chapter 1 MessageBox.Show("Finished - ADO.NET Basics updating first row.") Chapter 2 ' -close Data Components connection in Visual Studio .NET Chapter 3 conn.Close() - ADO.NET in Disconnected Environments Chapter 4 conn.Dispose() - ADO.NET in Connected Environments ex AsADO.NET SqlException ChapterCatch 5 - Handling Events connection Chapter 6 ' -close Integrating XML with ADO.NET Chapter 7 conn.Close() - Data Binding and Windows Forms Data-Bound Controls conn.Dispose() Chapter 8 - Constraints and Data Relations MessageBox.Show(ex.Message.ToString()) Chapter 9 - ADO.NET Exception Handling End Try Chapter 10 - Working with the ODBC .NET Data Provider End Sub Chapter 11 - Stored Procedures and Views

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 To - Developing Applications using ASP.NET add references to the System.Data and Note test theseDatabase samples,Web create a Windows application, Chapter 15 System.Data.SqlClient - Using ADO.NET in Xml Web Services namespaces, add two Button controls to the form, write code on the Chapter 16 button - ASP.NET Server Controls Data Binding event handlers, andand make sure SQL Server is up and running. Chapter 17 - Building Real-World Web Applications

Another18way of handling optimistic concurrency that you may be familiar with is by checking to see if a Chapter - Object-Relational Mapping in .NET timestamp the data source row has changed or the row number has changed on the row being Chapter 19 - on Mapped Objects: Performance Considerations andversion Data Binding updated. Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

The data providers don't really support pessimistic locking on the database because the connection to the

Chapter 22 is - SQL Server and so ADO.NET: Notes on Performance database not kept open, you must perform all locking with business logic on the DataSet. Appendix A - Relational Databases: Some Basic Concepts

You canBdo a form of pessimistic concurrency, however, using ADO.NET on the data source through Appendix - Commonly Used SQL Statements transactions. The wayFrequently to do this Asked is to keep the connection open on the database and create a transaction that Appendix C - ADO.NET Questions has a certain isolation level on a row. Listing 4-44 opens a connection and creates a transaction that locks out Index theofrows used in the Update of the Orders table in the Northwind database. List Figures List of Tables

Listing 4-44: Pessimistic Concurrency

List of Listings

List of Sidebars

Private Sub TestPessimisticConcurrency() Dim ConnectionString As String = "Integrated Security=SSPI;" & _ "Initial Catalog=Northwind;Data Source=MCB;" Dim conn As SqlConnection = New SqlConnection(ConnectionString) conn.Open() Try ' Create a transaction that locks the records of the query Dim tr As SqlTransaction = conn.BeginTransaction _ (IsolationLevel.RepeatableRead, "test") ' Create a command that updates the order of ' the database using the transaction\ Dim cmd As SqlCommand = New SqlCommand("UPDATE Orders SET " & _

"ShippedDate = '5/10/01', ShipCity = 'Columbus' WHERE " & _ Applied ADO.NET: Building Data-Driven Solutions "OrderID = 10248", conn, tr) ISBN:1590590732 by Mahesh Chand and David Talbot ' Execute the update Apress © 2003 (928 pages) cmd.ExecuteNonQuery() This text provides extensive coverage of ADO.NET technology ' Generate message including ADO.NET internals, namespaces, classes, and MessageBox.Show("Wait for keypress...") interfaces, and takes a comprehensive look at XML ' transaction As tr.Commit() namespacesis andcommitted classes, and how to integrate both with conn.Close() ADO.NET. Catch ex As SqlException MessageBox.Show(ex.Message.ToString()) Table ofEnd Contents Try Applied Data-Driven Solutions EndADO.NET—Building Sub Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3

- ADO.NET in Disconnected Environments Understanding Rollback, Commit, and Savepoints - ADO.NET in Connected Environments

Chapter 4

Chapter - Handling The Sql5 data providerADO.NET providesEvents some additional methods for dealing with transactions involving savepoints Chapter 6 Integrating XML with (which may not be available in allADO.NET data providers). Savepoints allow you to roll back to a "bookmarked" point in Chapter 7 - DataTable Binding anddescribes Windows Forms Data-Bound Controls the transaction. 4-17 these methods. Chapter 8


Chapter Table 4-17: 9 - ADO.NET Transaction Exception Methods Handlingin the Sql Data Provider Chapter 10 - Working with the ODBC .NET Data Provider

METHOD

DESCRIPTION


Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Rollback(SavePoint) Performs a rollback on a transaction to the previous database state. Chapter 13 - Developing a Custom Data Provider

Begin(IsolationLevel)

Begins a nested database transaction passing the isolation level.


Chapter Save(SavePointName) 15 - Using ADO.NET in Xml Web Equivalent Services to the Transact-SQL SAVE TRANSACTION in the SQL Chapter 16 - ASP.NET Server Controls Server and Data database. BindingAllows you to create a savepoint so that you can roll

back to a particular saved state of the database. Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Listing 19 4-45 shows an example of how you use savepoints SQLBinding Server. As you can see, first you establish a Chapter - Mapped Objects: Performance Considerations andinData connection Northwind database and open the connection. After that, by calling BeginTransaction Chapter 20 - with COMthe Interoperability and ADO.NET on the connection, you can return a SqlTransaction object, which you can use with your Command object. Chapter 21 - Messaging To establish the relationship with the Command object, you then pass the Transaction object in the constructor of Command.


Listing 4-45: Using Savepoints in the Sql Data Provider


Dim ConnectionString As String = "Integrated Security=SSPI;" & _ "Initial Catalog=Northwind;Data Source=MCB;" List of Tables Dim conn As SqlConnection = New SqlConnection(ConnectionString) List of Listings Dim tran As SqlTransaction = Nothing List of Figures

List of Sidebars

Try conn.Open() tran = conn.BeginTransaction("Transaction1") Dim cmd As SqlCommand = New SqlCommand(_ "INSERT INTO Customers (CustomerID, ContactName, CompanyName)" & _ "VALUES (516, 'Tim Howard', 'FireCon')", conn, tran) ' Call Save method tran.Save("save1") cmd.ExecuteNonQuery() MessageBox.Show("Tim is in the Database") cmd.CommandText = _

"INSERT INTO Customers (CustomerID, ContactName, CompanyName)" & _ Building Data-Driven Solutions "VALUESApplied (517,ADO.NET: 'Bob Hope', 'Hollywood')" ISBN:1590590732 by Mahesh Chand and David Talbot ' Call Save again Apress © 2003 (928 pages) tran.Save("save2") This text provides extensive coverage of ADO.NET technology cmd.ExecuteNonQuery() including ADO.NET internals, classes, and MessageBox.Show("Bob is in namespaces, the Database") interfaces, and takes a comprehensive look at XML cmd.CommandText = _ namespaces and classes, and how to integrate both with "INSERTADO.NET. INTO Customers(CustomerID, ContactName, CompanyName)" & _ "VALUES (518, 'Fred Astaire', 'Hollywood')" MessageBox.Show("Fred is in the Database") Table of Contents ' Save Applied ADO.NET—Building Data-Driven Solutions tran.Save("save3") Introduction cmd.ExecuteNonQuery() Chapter 1 ' -rollback ADO.NET Basics Chapter 2 tran.Rollback("save2") - Data Components in Visual Studio .NET transaction Chapter 3 ' -Commit ADO.NET the in Disconnected Environments Chapter 4 tran.Commit() - ADO.NET in Connected Environments Rolledback, only Tim Made it.") Chapter 5 MessageBox.Show("Transaction - Handling ADO.NET Events Chapter 6 conn.Close() - Integrating XML with ADO.NET Chapter 7 conn.Dispose() - Data Binding and Windows Forms Data-Bound Controls Catch exp As Exception Chapter 8 - Constraints and Data Relations If tran Is Nothing Then Chapter 9 - ADO.NET Exception Handling tran.Rollback() Chapter 10 - Working with the ODBC .NET Data Provider End If Chapter 11 - Stored Procedures and Views MessageBox.Show(exp.Message.ToString() & _ Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers "Transaction Rolledback, Tim didn't make it.") ChapterFinally 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET conn.Close() Chapter 15 - Using ADO.NET in Xml Web Services conn.Dispose() ChapterEnd 16 -Try ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Now that transaction is tied to theADO.NET Command object, you'll save the initial savepoint to the transaction and Chapter 20 the - COM Interoperability and then execute the first insertion into the database. After that you assign a new SQL Insert to the Command text Chapter 21 - Messaging and save the current transaction savepoint before executing the query. This Insert puts Bob Hope into the database. Appendix A - Relational Databases: Some Basic Concepts Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Appendix B - Commonly Used SQLInsert Statements Finally, you assign a new SQL to the Command text and save the current transaction savepoint before Appendix C -the ADO.NET Frequently Asked executing query. This Insert putsQuestions Fred into the database. Index

By of rolling back to the second savepoint, it's as if the second and third ExecuteNonQuery calls never List Figures happened, List of Tables so the first ExecuteNonQuery that puts Tim in the database is the only one that actually gets committed. List of ListingsIf there's an exception, then you can roll back the whole transaction. List of Sidebars

Executing Batches Another common concern for developers is the question of how to execute multiple INSERT statements in a batch. Again, using transactions, you can execute multiple queries in a batch and save or roll back changes based on some condition. For example, Listing 4-46 shows you how to execute multiple SQL queries. Listing 4-46: Executing Multiple SQL Queries Using SqlTransaction Dim ConnectionString As String = "Integrated Security=SSPI;" & _ "Initial Catalog=Northwind;Data Source=MCB;" Dim conn As SqlConnection = New SqlConnection(ConnectionString)

' Open the connection Applied ADO.NET: Building Data-Driven Solutions conn.Open() ISBN:1590590732 Mahesh Chandand and David Talbot ' Create by SqlCommand SqlTransaction objects Apress © 2003 (928 pages) Dim myCommand As New SqlCommand() provides extensive coverage of ADO.NET technology Dim transThis Astext SqlTransaction = Nothing including ADO.NET internals, namespaces, classes, and ' Create a local transaction using BeginTransaction interfaces, and takes a comprehensive look at XML ' All changes inside this and transaction will bewith saves or rollback namespaces and classes, how to integrate both ' after aADO.NET. call of Commit or Rollback trans = conn.BeginTransaction() myCommand.Connection = conn Table ofmyCommand.Transaction Contents = trans AppliedTry ADO.NET—Building Data-Driven Solutions Introduction myCommand.CommandText = _ Chapter 1 "INSERT - ADO.NET BasicsEmployees (FirstName, LastName, Address, City) " & _ INTO Chapter 2 " -VALUES Data Components ('Sundar', in Visual 'Lal','234 Studio .NET Lane, Rose Blvd', 'Chester')" Chapter 3 myCommand.ExecuteNonQuery() - ADO.NET in Disconnected Environments = _ Chapter 4 myCommand.CommandText - ADO.NET in Connected Environments Employees (FirstName, LastName, Address, City) " & _ Chapter 5 "INSERT - HandlingINTO ADO.NET Events ('Dinesh', 'Chand', '23rd Streed, Old Road', 'Delhi')" Chapter 6 " -VALUES Integrating XML with ADO.NET Chapter 7 myCommand.ExecuteNonQuery() - Data Binding and Windows Forms Data-Bound Controls myCommand.CommandText = _ Chapter 8 - Constraints and Data Relations "INSERT INTO Employees (FirstName, LastName, Address, City) " & _ Chapter 9 - ADO.NET Exception Handling " VALUES ('Rajesh', 'Kumar', '278 Meadowlake Drive', 'Downingtown')" Chapter 10 - Working with the ODBC .NET Data Provider myCommand.ExecuteNonQuery() Chapter 11 - Stored Procedures and Views If MessageBox.Show("Save Changes?", "SqlTransaction Commit Rollback", _ Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers MessageBoxButtons.YesNo, MessageBoxIcon.Question, Chapter 13 - Developing a Custom Data Provider MessageBoxDefaultButton.Button1) _ Chapter 14 Developing Database Web Applications using ASP.NET = MessageBoxDefaultButton.Button1 Then Chapter 15 -'Using ADO.NET in Xml Web Services Commit transaction and save changes Chapter 16 -trans.Commit() ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Else Chapter 18 -'Object-Relational Rollback transaction Mapping in .NET Chapter 19 -trans.Rollback() Mapped Objects: Performance Considerations and Data Binding End If Interoperability and ADO.NET Chapter 20 - COM exp As Exception ChapterCatch 21 - Messaging Dim str As and String = "Message :" + exp.Message Chapter 22 - SQL Server ADO.NET: Notes on Performance str = str Databases: + "Source :" Basic + exp.Source Appendix A - Relational Some Concepts MessageBox.Show(str) Appendix B - Commonly Used SQL Statements Finally Appendix C - ADO.NET Frequently Asked Questions conn.Close() Index conn.Dispose() List of Figures End Try List of Tables


Summary


ISBN:1590590732

In this chapter you saw the connected Apress © 2003 (928 pages)side of ADO.NET. The connected classes are based on the data providers. There This are atext number of data providers. Some of them are Sql, OleDb, and Odbc. As their provides extensive coverage of ADO.NET technology names suggest, they're designed to work with a specific kind of data including ADO.NET internals, namespaces, classes, andsource. For example, the Sql data interfaces, and with takesSQL a comprehensive look atand XMLthe OleDb data providers are designed to providers are designed to work Server databases, namespaces and Similarly, classes, and integrate bothdata withproviders to work with any ODBC work with OLE DB data sources. youhow cantouse the Odbc ADO.NET. data source. Each of these data providers is best used with the associated data source. Although their names are different, all data providers work in same way. Table of Contents

All the data providers follow a common model. A connection is created between the data provider and the data sources. You saw how to access different kinds of data sources using different kinds of data Introduction providers. After a connection is created, a DataAdapter or a command accesses and updates the data Chapter 1 - ADO.NET Basics source. A DataTable represents an in-memory cache for a database table. A DataSet is a collection of Chapter 2 - Data in Visual Studio .NET DataTables. A Components DataAdapter sits between a DataSet, and a data source and passes data back and Chapter 3 -Fill ADO.NET in Disconnected Environments forth. The method of a DataAdapter fills data from a data source to a DataSet based on the SQL Chapter 4 -on ADO.NET Connected statement which itinwas created.Environments The Update method of a DataAdapter reflects DataSet changes to Chapter 5 Handling ADO.NET Events the data source. You can use commands to execute SQL statements. You can execute direct SQL Chapter 6 - Integrating XML with ADO.NET commands such as INSERT, UPDATE, and DELETE to add, update, and delete data. Applied ADO.NET—Building Data-Driven Solutions

Chapter 7


ADataReader is another component used to read data from a data source through a Chapter 8 - Constraints andimportant Data Relations DataAdapter. You can use the ExecuteReader method of a Command to get data in a DataReader. Chapter 9 - ADO.NET Exception Handling You can also execute stored procedures and views using a command. You also learned how to handle Chapter 10 - Working with the ODBC .NET Data Provider concurrency and locking issues using transactions in ADO.NET. Chapter 11 - Stored Procedures and Views

Chapter 12 -chapter Oracle, SQLXML, and Otheron .NET Data Providers In the next you'll concentrate event handling in ADO.NET. Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

ADO.NET: Building Data-Driven Solutions Chapter Applied 5: Handling ADO.NET Events ISBN:1590590732 by Mahesh Chand and David Talbot

Overview


This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Events are usefulinterfaces, for notifying andyou takes when a comprehensive some action happens look at XML to an object. An event can have a method, namespaces and classes, and how an to integrate both with called an event handler, associated with it. When event occurs, the associated event handler (method) ADO.NET.

is executed. An event can have multiple event handlers. In Visual Basic .NET (VB .NET), you use the AddHandler and RemoveHandler statements to add and remove event handlers. Table of Contents

AddHandler takes two arguments: the name of an event from an object and an expression that evaluates to a delegate. You use the AddressOf statement to pass a reference to the delegate. For Introduction example, the following code adds an event handler: Applied ADO.NET—Building Data-Driven Solutions Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


AddHandler MyObject.Event1, AddressOf Me.MyEventHandler

Chapter 5 - Handling ADO.NET Events RemoveHandler disconnects an event from an event handler, and it uses the same syntax as Chapter AddHandler. 6 - Integrating For example, XML with the ADO.NET following code removes the event handler: Chapter 7


Chapter 8 - Constraints and Data Relations AddressOf Me.MyEventHandler RemoveHandler MyObject.Event1, Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

Note want to learnand more about events and delegates in VB .NET, see the VB .NET language Chapter 12 If- you Oracle, SQLXML, Other .NET Data Providers in the documentation. Chapter 13 reference - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

In this chapter, you'll learn how you can handle events for ADO.NET objects. As discussed in the past two

Chapter 15 you - Using in Xml Web Services chapters, canADO.NET divide ADO.NET classes into two groups: disconnected classes and connected classes. Chapter 16 ASP.NET Server Controls and Binding TheSystem.Data namespace defines Data common event handlers and event argument classes for all data Chapter 17 -As Building Real-World Applications providers. you can see fromWeb Figure 5-1, event handler classes are derived from the Delegate class Chapter 18 -argument Object-Relational in .NET and event classes Mapping are derived from the EventArgs class. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - 5-1: Oracle, SQLXML, andand Other .NET Data Providers Figure Event handler event argument classes defined in the System.Data namespace Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Note data providers areServices derived from a common hierarchy, so all data providers support Chapter 15 ADO.NET - Using ADO.NET in Xml Web the same set of events.

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications DataColumnChangeEventHandler is an event handler for DataColumn when a value is being Chapter 18for - Object-Relational Mapping in .NET changed a column in a DataRow. DataRowChangeEventHandler is an event handler that handles Chapter 19 - MappedRowChanged, Objects: Performance Considerations and Data Binding theRowChanging, RowDeleting, and RowDeleted events of a DataTable. The Chapter 20 - COM Interoperability andevent ADO.NET FillErrorEventHandler is an handler that handles a DataAdapter'sFill event. If an error Chapter occurred 21 during - Messaging the fill operation, the FillError fires, which executes FillErrorEventHandler.

MergeFailedEventHandler handles theonDataSet's MergeFailed event that occurs when a Chapter 22 - SQL Server and ADO.NET: Notes Performance DataSet operation fails. Whenever connection's state changes, the StateChange event Appendix A -merge Relational Databases: Some BasicaConcepts occurs.StateChangeEventHandler handles this event. Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Besides the event handler and event argument classes defined in the System.Data namespace, the data provider event handler and event argument classes are defined in the data provider-specific List of Figures namespace.Figure 5-2 shows the OleDb data provider event handlers and event argument classes. Index

List of Tables


Figure 5-2: OleDb data provider event handler and event arguments Applied ADO.NET: Building Data-Driven Solutions

ISBN:1590590732 by Mahesh Chand and David Talbot OleDbInfoMessageEventHandler handles the InfoMessage event of the OleDbConnection. An Apress © 2003when (928 pages) InfoMessage event occurs a provider sends a warning or an informational message to the application. This text provides extensive coverage of ADO.NET technology

including ADO.NET internals, namespaces, classes, and and takes comprehensive look is atcalled XML on a DataAdapter. TheRowUpdatedinterfaces, event occurs when aan Update method namespaces and classes, and how integrate both with of the OleDbDataAdapter. Apart OleDbRowUpdatedEventHandler handles the to RowUpdated event ADO.NET. from the RowUpdated event, there's one more update-related event: RowUpdating. As you can guess from its name, this event occurs when a row is being updated, which means before the command is executed against a data source. OleDbRowUpdatingEventHandler is responsible for handling this Table of Contents event. Applied ADO.NET—Building Data-Driven Solutions Introduction

In this chapter, you'll use the Sql data provider.

Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions Working with Connection Events by Mahesh Chand and David Talbot

ISBN:1590590732

TheConnectionApress object© has 2003 two (928 events pages) that notify the application if a connection state changes. You can use these eventsThis to retrieve informational messages a data source or to determine if the state of a text provides extensive coverage from of ADO.NET technology Connection has changed. These two events are InfoMessage and StateChange. The including ADO.NET internals, namespaces, classes, and interfaces, takes comprehensive look at XML InfoMessage event occursand when anainformational message is returned from a data source. The namespaces and these classes, and how toThe integrate both with event occurs only when the state exception handling doesn't catch messages. StateChange ADO.NET. of a connection changes. TheInfoMessage event receives an InfoMessageEventArgs object. The InfoMessageEventArgs is as follows:

Table of Contents


Public Sub SqlInfoMessageEventHandler(_ Chapter 1 Delegate - ADO.NET Basics ByVal- Data sender As Object, _ Components in Visual Studio .NET ByVal e As SqlInfoMessageEventArgs _

Chapter 2 Chapter 3


Chapter 4


Chapter 5


Chapter 6


)

Chapter 7 - Data sender Binding and Windows In this example, is the sourceForms of theData-Bound event and eControls is an SqlInfoMessageEventArgs object that Chapter 8 the - Constraints contains event data.and Data Relations Chapter 9


Table 5-1 describes the InfoMessageEventArgs properties.


Table 5-1: InfoMessageEventArgs Properties

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider PROPERTY DESCRIPTION Chapter 14 - Developing Database Web Applications using ASP.NET

ErrorCode

Returns the HRESULT following the ANSI SQL standard for the database


Chapter 16 - ASP.NET Serverthe Controls and of Data Bindingsent from the data source Errors Returns collection warnings Chapter 17 - Building Real-World Web Applications

Message

Returns the full text of the error


Chapter 19 - Mapped Objects: and Data the Binding Source Returns thePerformance name of theConsiderations object that generated error Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Caution Some of these members may be different for other data providers. For example, the Sql data Chapter 22 - SQL provider Serverdoesn't and ADO.NET: have theNotes ErrorCode on Performance property. Appendix A - Relational Databases: Some Basic Concepts

TheStateChange event occurs when the state of a Connection changes. The StateChangeEventHandler is as follows:



Public Delegate Sub StateChangeEventHandler(_ List of Figures List ofByVal Tables sender As Object, _ List ofByVal Listings e As StateChangeEventArgs _

)

List of Sidebars

As you can see from the definition of StateChangeEventHandler, this handler has a second argument calledStateChangeEventArgs. You can use StateChangeEventArgs to determine the change in state of the Connection using the OriginalState and CurrentState properties. The OriginalState property represents the original state of the Connection, and the CurrentState property represents the current state of the connection. The ConnectionState enumeration defines members for connection states (see Table 5-2). Table 5-2: The ConnectionState Enumeration Members

PROPERTY


Broken

ISBN:1590590732 by Mahesh Chand and David Talbot This state occurs if the connection is broken after it was opened. Apress © 2003 (928 pages)

This The text connection provides extensive is closed.coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Connecting interfaces, The connection is connecting to a data and takes a comprehensive look source. at XML namespaces and classes, and how to integrate both with Executing ADO.NET. TheConnection object is executing a command.

Closed

Fetching Table of Contents Open

TheConnection object is retrieving data. The connection is open.


To test 1events, createBasics a Windows application and add a SqlConnection to the form by dragging a Chapter - ADO.NET SqlConnection componentinfrom theStudio Toolbox Chapter 2 - Data Components Visual .NETData tab. Then add two Button controls to the form: an Open button and a Close button. Now write the InfoMessage and StateChange event handlers (see Chapter 3 - ADO.NET in Disconnected Environments Listing 45-1). As you can see from Listing 5-1, you generate messages if any of the events occur. Chapter - ADO.NET in Connected Environments Chapter 5


Chapter 6


Chapter 7


Listing 5-1: Writing Event Handlers for the InfoMessage and StateChange Events

' The8 InfoMessage event handler Chapter - Constraints and Data Relations Private Sub SqlConnection1_InfoMessage(ByVal sender As System.Object, _ Chapter 9 - ADO.NET Exception Handling ByVal e As System.Data.SqlClient.SqlInfoMessageEventArgs) _ Chapter 10 - Working with the ODBC .NET Data Provider Handles SqlConnection1.InfoMessage Chapter 11 - Stored Procedures and Views Dim err As SqlError Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers For Each err In e.Errors Chapter 13 - Developing a Custom Data Provider MessageBox.Show(err.Source.ToString() + err.State.ToString() & _ Chapter 14 - Developing Database Web Applications using ASP.NET err.Source.ToString() + err.Message.ToString()) ChapterNext 15 - Using ADO.NET in Xml Web Services Chapter - ASP.NET Server Controls and Data Binding End16Sub Chapter 17 - Building Real-World Web Applications 'The state change event handler Chapter 18 - Object-Relational Mapping in .NET Private Sub SqlConnection1_StateChange(ByVal sender As System.Object, _ Chapter 19 -eMapped Objects: Performance Considerations and Data Binding ByVal As System.Data.StateChangeEventArgs) _ Chapter Handles 20 - COM SqlConnection1.StateChange Interoperability and ADO.NET State: " + e.OriginalState.ToString() & _ ChapterMessageBox.Show("Original 21 - Messaging Current State :" + e.CurrentState.ToString()) Chapter 22 ", - SQL Server and ADO.NET: Notes on Performance End ASub Appendix - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index

Now let's write code to call these events. You write code on the Open and Close button click event handlers. On the Open button click event handler, you open a SqlConnection, and on the Close event List of Tables handler, you close the connection (see Listing 5-2). List of Figures

List of Listings

List of Sidebars Listing 5-2: Writing Code That Executes Connection Events

' Open button click event handler Private Sub OpenBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles OpenBtn.Click ' Create a Connection Object Dim ConnectionString As String = "Integrated Security=SSPI;" & _ "Initial Catalog=Northwind;Data Source=MCB;" SqlConnection1.ConnectionString = ConnectionString ' Open the connection If SqlConnection1.State ConnectionState.Open Then SqlConnection1.Open()

End If Applied ADO.NET: Building Data-Driven Solutions End Sub ISBN:1590590732 by Mahesh Chand and David Talbot ' Close button click event handler Apress © 2003 (928 pages) Private Sub CloseBtn_Click(ByVal sender As System.Object, _ text provides extensiveHandles coverage of ADO.NET technology ByVal e As This System.EventArgs) CloseBtn.Click including ADO.NET internals, namespaces, classes, and Try interfaces, and takes a comprehensive look at XML SqlConnection1.Close() namespaces and classes, and how to integrate both with Catch expADO.NET. As SqlException MessageBox.Show(exp.Message.ToString()) End Try TableEnd of Contents Sub Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Note may notice oneinthing when you.NET compile your code. Even though you added Chapter 2 You - Data Components Visual Studio SqlConnection using the wizard, you Chapter 3 - ADO.NET in Disconnected Environments still need to import the System.Data.SqlClient the following line: Imports System.Data.SqlClient. Chapter 4 namespace - ADO.NET inusing Connected Environments Chapter 5


The output of clicking the Open button looks like Figure 5-3. It shows that the original state of the - Integrating XML with ADO.NET connection was Closed, and the current state is Open.

Chapter 6 Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - 5-3: UsingOutput ADO.NET in Xml Web Services Figure of the Open button click Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

The output of the Close button click looks like Figure 5-4. It shows that the original state of the connection wasOpen, and the current state is Closed.


Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List ofFigure Figures5-4: Output of the Close button click List of Tables List of Listings List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions Working with DataAdapter Events by Mahesh Chand and David Talbot

ISBN:1590590732

TheDataAdapter has ©a 2003 FillError Apress (928 pages) event that occurs when there's an error during a Fill method. It allows a user to determine whether a fill operation should continue. FillError may occur when data This text provides extensive coverage of ADO.NET technology from a database including can't be converted to a Common Language Runtime ADO.NET internals, namespaces, classes, and (CLR) type without losing precision; interfaces, and casting takes a isn't comprehensive look at XML or it may occur when data type valid. namespaces and classes, and how to integrate both with

ADO.NET. FillErrorEventHandler handles the FillError event. The event handler receives an argument of typeFillErrorEventArgs containing data related to this event. The FillErrorEventHandler is defined as follows: Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Public Delegate Sub FillErrorEventHandler(_ Introduction ByVal sender Basics As Object, _ Chapter 1 - ADO.NET ByVal- Data e As FillErrorEventArgs _ Components in Visual Studio .NET

Chapter 2

)

Chapter 3


Chapter 4


Chapter 5 - Handling ADO.NET In this example, sender is theEvents source of the event and e is the FillErrorEventArgs that contains the Chapter 6 Integrating XML with ADO.NET event data. Chapter 7


Table 5-3 theand FillErrorEventArgs properties. Chapter 8 -describes Constraints Data Relations Chapter 9


Table 5-3: FillErrorEventArgs Members Chapter 10 - The Working with the ODBC .NET Data Provider Chapter 11 - StoredDESCRIPTION Procedures and Views PROPERTY Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Continue Represents a value Chapter 13 - Developing a Custom Data indicating Provider whether to continue the Fill operation Chapter 14 - Developing Database Web Applications using ASP.NET DataTable Returns the data table being updated when the error occurred Chapter 15 - Using ADO.NET in Xml Web Services

Errors Returns errors and Data Binding Chapter 16 - ASP.NET Serverthe Controls Chapter 17 - Building Real-World Webbeing Applications Values Returns the rows updated when the error occurred Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

TheRowUpdated and RowUpdating events are two more events supported by a DataAdapter. The Chapter 20 - COM Interoperability and ADO.NET RowUpdating event occurs when an Update method is called before a command is executed against Chapter 21 - Messaging the data The RowUpdated when a command is executed. Chapter 22source. - SQL Server and ADO.NET:event Notesoccurs on Performance Appendix A - Relational Databases: Some Basic Concepts

TheRowUpdated event handler receives an argument SqlRowUpdatedEventArgs containing data

Appendix B this - Commonly Used SQL Statements related to event. The SqlRowUpdatedEventArgs contains the members in Table 5-4. Appendix C - ADO.NET Frequently Asked Questions Index Table 5-4: The SqlRowUpdatedEventArgs Members List of Figures ListPROPERTY of Tables

DESCRIPTION

ListCommand of Listings

Returns the Command object executed when Update is called

List of Sidebars

Errors

Returns errors generated during the Update operation

RecordsAffected

Returns the number of rows affected during inserting, updating, and deleting

Row

Returns the data row sent through an Update

StatementType

Returns the SQL statement type

Status

Returns the UpdateStatus of a command

TableMapping

Returns the DataTableMapping sent through an Update

Similarly to the RowUpdated event, the RowUpdating event handler receives an argument of type

SqlRowUpdatedEventArgs that defines the same properties as the SqlRowUpdated with the same Applied ADO.NET: Building Data-Driven Solutions meaning. by Mahesh Chand and David Talbot

ISBN:1590590732

To test the DataAdapter Apress © 2003 events (928 pages) and event handlers, create a Windows application, add a Button control to the form, and itsextensive name to DataAdapterEventsTestBtn. This textchange provides coverage of ADO.NET technology Also add a including ADO.NET namespaces, classes, and SqlDataAdapter by dragging theinternals, SqlDataAdapter from the Toolbox Data tab to the form and interfaces, and takes a comprehensive look at XML Wizard. Select the CompanyName, configure the DataAdapter using the Data Adapter Configuration namespaces and classes, and how to integrate both with ContactName, and CustomerID columns from the Customers table. The final SELECT statement looks ADO.NET. like the following: Table of Contents SELECT CustomerID, CompanyName, ContactName FROM Customers Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Note Chapter 2 for more details about the Data Adapter Configuration Wizard. Chapter 2 See - Data Components in Visual Studio .NET Chapter 3


Now add all three FillError,RowUpdating, and RowUpdated event handlers manually. Listing 5-3 - ADO.NET in Connected Environments defines the event handler bodies for these three methods.

Chapter 4 Chapter 5


Chapter - Integrating XML with ADO.NET Listing65-3: SqlDataAdapter Event Handler Bodies Chapter 7


Chapter 8


'FillError event handler - ADO.NET Exception Handling Private Shared Sub FillError(ByVal sender As Object, _ Chapter 10 Working the ODBC .NET Data Provider ByVal -args Aswith FillErrorEventArgs) Chapter 9

Chapter 11 - Stored Procedures and Views Chapter - Oracle, SQLXML, and Other .NET Data Providers End12Sub Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET 'RowUpdating event handler Chapter Protected 15 - UsingShared ADO.NETSub in Xml OnRowUpdating(ByVal Web Services sender As Object, _

ByVal As SqlRowUpdatingEventArgs) Chapter 16 -eASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

End18Sub Chapter - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

'RowUpdated event handler Chapter 20 - COM Interoperability and ADO.NET Protected Shared Sub OnRowUpdated(ByVal sender As Object, _ ByVal e As SqlRowUpdatedEventArgs)



End Sub

Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of you Figures Now need to write code on these event handlers. Listing 5-4 shows the source code for the List of Tables FillError event. You can also use other members of EventArgs to get more details. This event List handler of Listings will execute when an error occurs during the Fill method. List of Sidebars

Listing 5-4: DataAdapter FillError Event Handler Code 'FillError event handler Private Shared Sub FillError(ByVal sender As Object, _ ByVal args As FillErrorEventArgs) If args.Errors.GetType() Is Type.GetType("System.OverflowException") Then MessageBox.Show("Error in Fill operation for table " & _ args.DataTable.TableName & _ ", Error Message: " + args.Errors.Message.ToString() & _ ", Source: " + args.Errors.Source.ToString()) args.Continue = True

End If End Sub


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including classes, Listing 5-5 and Listing 5-6 ADO.NET show the internals, code for namespaces, the RowUpdated andand RowUpdating event handlers. The interfaces, and takes a comprehensive look at XML RowUpdated event handler is called when a row is updated using the Update method of a namespaces and classes, and how to integrate both with DataAdapter, ADO.NET. and RowUpdating is called when a row is updating.

Listing 5-5: The RowUpdated Event Handler Table of Contents Applied ADO.NET—Building Data-Driven Solutions 'RowUpdated event handler Introduction Protected Shared Sub OnRowUpdated(ByVal sender As Object, _ Chapter 1 -eADO.NET Basics ByVal As SqlRowUpdatedEventArgs) ChapterIf 2 e.Status - Data Components in Visual Studio .NET = UpdateStatus.ErrorsOccurred Then Chapter 3 MessageBox.Show("Error - ADO.NET in Disconnected Environments Message: " + e.Errors.Message.ToString() & _ Chapter 4 - ADO.NET in Connected ", Source: Environments " + e.Errors.Source.ToString())

e.Errors.Message Chapter 5 e.Row.RowError - Handling ADO.NET=Events = XML UpdateStatus.SkipCurrentRow Chapter 6 e.Status - Integrating with ADO.NET ChapterElse 7 - Data Binding and Windows Forms Data-Bound Controls Chapter 8 MessageBox.Show("Updated") - Constraints and Data Relations ChapterEnd 9 -If ADO.NET Exception Handling

End Sub

Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

Listing 5-6: The RowUpdating Event Handler


'RowUpdating event handler Protected Shared Sub OnRowUpdating(ByVal sender As Object, _ Chapter 17 - Building Real-World Web Applications ByVal e As SqlRowUpdatingEventArgs) Chapter 18 - Object-Relational Mapping in .NET ' Inserting Chapter 19 - Mapped Objects: Performance Considerations and Data Binding If e.StatementType = StatementType.Insert Then Chapter 20 - COM Interoperability and ADO.NET MessageBox.Show("Inserting") ChapterEnd 21 -If Messaging Chapter'22 SQL Server and ADO.NET: Notes on Performance Updating Appendix A Relational Databases:=Some Basic Concepts If e.StatementType StatementType.Update Then Appendix B - Commonly Used SQL Statements MessageBox.Show("Updating") Appendix C -If ADO.NET Frequently Asked Questions End Index 'Deleting If e.StatementType = StatementType.Delete Then List of Figures MessageBox.Show("Deleting") List of Tables End If List of Listings ' Selecting List of Sidebars If e.StatementType = StatementType.Select Then MessageBox.Show("Selecting") End If End Sub Chapter 16 - ASP.NET Server Controls and Data Binding

As you can see from Listing 5-6, you can compare the StatementType member of OleDbRowUpdatingEventArgs to the StatementType enumeration to find out the statement type. TheStatementType enumeration defines Select,Insert,Update, and Delete members. To test these events you can write code that fills a DataSet and calls the Update method of the

DataAdapter. You add an event handler for the button by double-clicking it and writing the code in Applied ADO.NET: Data-Driven Solutions Listing 5-7. As you can see, you call Building AddHandler and RemoveHandler. by Mahesh Chand and David Talbot

ISBN:1590590732

Apress 2003 (928 pages) Listing 5-7: Calling the©DataAdapter's Fill and Update Methods This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Private Sub DataAdapterEventsTestBtn_Click(ByVal interfaces, and takes a comprehensive look at XML sender As System.Object, _ ByVal e As namespaces System.EventArgs) Handles DataAdapterEventsTestBtn.Click and classes, and how to integrate both with ' Create ADO.NET. InsertCommand

SqlDataAdapter1.InsertCommand = New SqlCommand _ ("INSERT INTO Customers (CustomerID, CompanyName)" & _ Table of Contents "VALUES(@CustomerID, @CompanyName)", SqlConnection1) Applied ADO.NET—Building Data-Driven Solutions SqlDataAdapter1.InsertCommand.Parameters.Add("@CustomerID", _ Introduction SqlDbType.VarChar, 5, "CustomerID") ChapterSqlDataAdapter1.InsertCommand.Parameters.Add("@CompanyName", 1 - ADO.NET Basics _ ChapterSqlDbType.VarChar, 2 - Data Components in Visual Studio .NET 30, "CompanyName") Chapter'3 Opening - ADO.NET in Disconnected Environments Connection ChapterSqlConnection1.Open() 4 - ADO.NET in Connected Environments Chapter'5 Create - Handling ADO.NET and Fill Events DataSet ChapterDim 6 -custDS Integrating AsXML DataSet with ADO.NET = New DataSet() "Customers") ChapterSqlDataAdapter1.Fill(custDS, 7 - Data Binding and Windows Forms Data-Bound Controls ' add handlers Chapter 8 - Constraints and Data Relations AddressOf OnRowUpdating ChapterAddHandler 9 - ADO.NET SqlDataAdapter1.RowUpdating, Exception Handling AddHandler SqlDataAdapter1.RowUpdated, AddressOf OnRowUpdated Chapter 10 - Working with the ODBC .NET Data Provider ' Add a new data row and call Update method Chapter 11 - Stored Procedures and Views ' of data adapter Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Dim custRow As DataRow = custDS.Tables("Customers").NewRow() Chapter 13 - Developing a Custom Data Provider custRow("CustomerID") = "NEWCO" Chapter 14 - Developing Database Web Applications using ASP.NET custRow("CompanyName") = "New Company" Chapter 15 - Using ADO.NET in Xml Web Services custDS.Tables("Customers").Rows.Add(custRow) Chapter 16 - ASP.NET Server Controls and Data Binding SqlDataAdapter1.Update(custDS, "Customers") ChapterRemoveHandler 17 - Building Real-World Web Applications SqlDataAdapter1.RowUpdating, AddressOf OnRowUpdating ChapterRemoveHandler 18 - Object-Relational Mapping in .NET SqlDataAdapter1.RowUpdated, AddressOf OnRowUpdated Chapter'19 - Mapped Performance Considerations and Data Binding Close theObjects: connection ChapterSqlConnection1.Close() 20 - COM Interoperability and ADO.NET ChapterSqlConnection1.Dispose() 21 - Messaging Chapter End22Sub - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

You can also use SelectCommand,UpdateCommand, and DeleteCommand objects to select, update, and delete data from the table. See the "The Command: Executing SQL Statements" section of Chapter 4 List of Figures for more on using commands. Index

List of Tables

List of if Listings Now you run the application, you'll see the insert message; if you click the button more than once, you'll List Sidebars getofthe following error message: "Violation of PRIMARY KEY constraint 'PK_Customers.' Cannot insert

duplicate key in object 'Customers.'"

Applied ADO.NET: Building Data-Driven Solutions Working with DataSet Events by Mahesh Chand and David Talbot

ISBN:1590590732

ADataSet has aApress MergeFailed event that occurs when merging two DataSets fails. © 2003 (928 pages) MergeFailedEventHandler handles thecoverage MergeFailed event, which receives an argument of type This text provides extensive of ADO.NET technology MergeFailedEventArgs containing data related to this event. The including ADO.NET internals, namespaces, classes, and MergeFailedEventHandler is interfaces, and takes a comprehensive look at XML defined as follows: namespaces and classes, and how to integrate both with ADO.NET.

Public Delegate Sub MergeFailedEventHandler(_ ByVal sender As Object, _ Table ByVal of Contents e As MergeFailedEventArgs _ Applied ADO.NET—Building Data-Driven Solutions ) Introduction Chapter 1

- ADO.NET Basics

In this example, sender is the source of the event, and e is the MergeFailedEventArgs object that Chapter 2 - Data Components in Visual Studio .NET contains the event data. Chapter 3 - ADO.NET in Disconnected Environments Chapter 4 - ADO.NET in Connected Environments MergeFailedEventArgs has Conflict and Table properties. The Conflict property returns a Chapter 5 Handling ADO.NET Events description of the merge conflict, and the Table property returns the name of the data table. Listing 5-8 Chapter 6 example - Integrating XML with ADO.NET event handler. shows an of the MergeFailed Chapter 7 - Data Binding and Windows Forms Data-Bound Controls

Listing85-8: Writing Code to Call MergeFailed Event Handler Chapter - Constraints and Data Relations Chapter 9


Chapter Working with the ODBC .NET Data Provider ByVal10e -As System.EventArgs) Handles MergetFailedEventBtn.Click ChapterDim 11 -ConnectionString Stored Procedures and Views As String = "Integrated Security=SSPI;" & _ Chapter"Initial 12 - Oracle,Catalog=Northwind;Data SQLXML, and Other .NET Data Providers Source=MCB;"

As SqlConnection = New SqlConnection() ChapterDim 13 -conn Developing a Custom Data Provider ConnectionString Chapterconn.ConnectionString 14 - Developing Database Web=Applications using ASP.NET String = "SELECT * FROM Employees" ChapterDim 15 -sql UsingAs ADO.NET in Xml Web Services As SqlDataAdapter New SqlDataAdapter(sql, conn) ChapterDim 16 -da ASP.NET Server Controls and = Data Binding As Real-World DataSet Web = New DataSet() ChapterDim 17 -ds1 Building Applications da.Fill(ds1) sql = "SELECT * FROM Customers" Chapter 19 - Mapped Objects: Performance Considerations and Data Binding da = New SqlDataAdapter(sql, conn) Chapter 20 - COM Interoperability and ADO.NET Dim ds2 As DataSet = New DataSet() Chapter 21 - Messaging da.Fill(ds2) Chapter 22 - SQL Server and ADO.NET: Notes on Performance ' Add MergeFailed Event handler Appendix A - Relationalds1.MergeFailed, Databases: Some Basic New Concepts AddHandler MergeFailedEventHandler _ Appendix B - Commonly Used SQL Statements (AddressOf DataSetMergeFailed) Appendix C - ADO.NET Frequently Asked Questions ds1.Merge(ds2) Index 'Remove the MergeFailed handler List of Figures RemoveHandler ds1.MergeFailed, AddressOf DataSetMergeFailed List of Tables conn.Close() conn.Dispose() List of Listings End Sub List of Sidebars ' MergeFailed event handler Private Shared Sub DataSetMergeFailed(ByVal sender As Object, _ ByVal args As MergeFailedEventArgs) MessageBox.Show("Merge failed for table " & args.Table.TableName & _ "Conflict = " & args.Conflict) End Sub Chapter 18 - Object-Relational Mapping in .NET

As you can see from Listing 5-8, you write an event handler that will be called when a Merge method on a DataSet fails.


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions Working with DataTable Events by Mahesh Chand and David Talbot

ISBN:1590590732

ADataTable represents a table a DataSet. A DataTable provides many events that can be tracked Apress © 2003 (928 of pages) down by an application (see Table 5-5). This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Table 5-5: The DataTable Events

namespaces and classes, and how to integrate both with ADO.NET. DESCRIPTION

EVENT

ColumnChanged

This event occurs when a value of a column has been changed.

Table of Contents

ColumnChanging This event occurs when a new value is being added to a column. Applied ADO.NET—Building Data-Driven Solutions Introduction RowChanged

This event occurs when value of a row in the table is changed.

Chapter 1

- ADO.NET Basics

Chapter 2


RowChanging

This event occurs when a row in a table is changing.

Chapter 3 - ADO.NET in This Disconnected Environments RowDeleted event occurs when a row in a table is deleted. Chapter 4 - ADO.NET in Connected Environments

RowDeleting

This event occurs when a row is being deleted.

Chapter 5


Chapter 6


Chapter 7 - Data Binding and Windows Forms Data-Bound Controls TheColumnChangedEventHandler handles the ColumnChanged event and is defined as follows: Chapter 8 - Constraints and Data Relations Chapter 9

- ADO.NET Exception Handling Public Delegate Sub DataColumnChangeEventHandler(_

Chapter 10 - Working ODBC .NET ByVal senderwith Asthe Object, _ Data Provider Chapter 11 - Stored and Views ByVal e As Procedures DataColumnChangeEventArgs _ Chapter 12 Oracle, SQLXML, and Other .NET Data Providers ) Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

In this example, is in theXml source of the event and e is DataColumnChangedEventArgs that Chapter 15 - Usingsender ADO.NET Web Services contains event data. Chapter 16the - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

ColumnChangingEventHandler handles the ColumnChanging event and is defined as follows:



Public Delegate Sub DataColumnChangeEventHandler(_ ByVal sender As Object, _ Chapter 21 - Messaging ByVal e As DataColumnChangeEventArgs _ Chapter 22 - SQL Server and ADO.NET: Notes on Performance ) Chapter 20 - COM Interoperability and ADO.NET


In this example, sender is the source of the event and e is DataColumnChangingEventArgs that Appendix C - ADO.NET Frequently Asked Questions contains the event data. Index List of Figures

Similar to these two event handlers, RowChangedEventHandler,RowChangingEventHandler, RowDeletedEventHandler, and RowDeletedEventHandler handle the RowChanged, List of Listings RowChanging,RowDeleted, and RowDeleting events, respectively. Definitions of these event List of Sidebars handlers are similar to DataColumnChangingEventHandler and DataColumnChangedEventHandler—except the EventArgs class is different. List of Tables

To test these events you'll create a DataTable, add DataRows to it, and then update and delete rows from the table. Listing 5-9 creates a DataTable, adds three columns—id, name, and address—adds data to the table and changes the column of the table. It also calls the ColumnChanged and ColumnChanging event handlers. You write the code for the ColumnChanged and ColumnChanging event handlers in the Column_changed and Column_Changing methods. You can write this code on a button click event handler. Listing 5-9: Writing the ColumnChanging and ColumnChanged Event Handlers


Private Sub ColumnChange_Click(ByVal sender As System.Object, _ ISBN:1590590732 by Mahesh Chand and David Talbot ByVal e As System.EventArgs) Handles ColumnChange.Click Apress © 2003 (928 pages)


Dim custTable As DataTable = New DataTable("Customers") including ADO.NET internals, namespaces, classes, and ' add columns interfaces, and takes a comprehensive look at XML custTable.Columns.Add("id", namespaces and classes, andType.GetType("System.Int32")) how to integrate both with ADO.NET. custTable.Columns.Add("name", Type.GetType("System.String")) custTable.Columns.Add("address", Type.GetType("System.String")) ' add a ColumnChanged & ColumnChanging event handler for the table. Table of Contents AddHandler custTable.ColumnChanged, New DataColumnChangeEventHandler _ Applied ADO.NET—Building Data-Driven Solutions (AddressOf Column_Changed) Introduction AddHandler custTable.ColumnChanging, New DataColumnChangeEventHandler _ Chapter 1 - ADO.NET Basics (AddressOf Column_Changing) Chapter ' 2 add - Data Components Two rows in Visual Studio .NET ChaptercustTable.Rows.Add(New 3 - ADO.NET in Disconnected Environments Object() {1, "name1", "address1"}) ChaptercustTable.Rows.Add(New 4 - ADO.NET in Connected Environments Object() {2, "name2", "address2"}) Chapter'5 Save - Handling ADO.NET Events changes ChaptercustTable.AcceptChanges() 6 - Integrating XML with ADO.NET Chapter'7 change - Data Binding Address and Windows column Forms in all Data-Bound the rows Controls Dim row As DataRow Chapter 8 - Constraints and Data Relations Each row In custTable.Rows Chapter For 9 - ADO.NET Exception Handling row("address") = ODBC "New .NET address" Chapter 10 - Working with the Data Provider Next row Chapter 11 - Stored Procedures and Views Removing event and handlers Chapter'12 - Oracle, SQLXML, Other .NET Data Providers RemoveHandler custTable.ColumnChanged, AddressOf Column_Changed Chapter 13 - Developing a Custom Data Provider RemoveHandler custTable.ColumnChanging, AddressOf Column_Changing Chapter 14 - Developing Database Web Applications using ASP.NET End Sub Chapter 15 - Using ADO.NET in Xml Web Services


' Column changed event handler Private Shared Sub Column_Changed(ByVal sender As Object, _ Chapter 18 -eObject-Relational Mapping in .NET ByVal As DataColumnChangeEventArgs) Chapter 17 - Building Real-World Web Applications

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET MessageBox.Show("Column_Changed Event: " + " ," & _ Chapter 21 - Messaging + " ," + e.Column.ColumnName + " ," & _ e.Row("name") Chapter 22 - SQL Server and ADO.NET: Notes on Performance e.Row("name", DataRowVersion.Original)) Appendix A - Relational Databases: Some Basic Concepts

End BSub Appendix - Commonly Used SQL Statements ' Column Changing event handler Appendix C - ADO.NET Frequently Asked Questions Private Shared Sub Column_Changing(ByVal sender As Object, _ Index ByVal e As DataColumnChangeEventArgs) List of Figures MessageBox.Show("Column_Changing Event: " + " ," & _ List of Tables e.Row("name") + " ," + e.Column.ColumnName + " ," & _ e.Row("name", DataRowVersion.Original)) List of Sidebars End Sub List of Listings

Listing 5-10 creates a DataTable, adds three columns—id, name, and address—adds data to the table, and changes the column of the table. It also calls the RowChanging and RowChanged event handlers. Listing 5-10: Writing the RowChanging and RowChanged Event Handlers ' Row Changed and Row Changing Events Caller Private Sub UpdateRow_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles UpdateRow.Click

AppliedAs ADO.NET: Building Data-Driven Solutions Dim custTable DataTable = New DataTable("Customers") ISBN:1590590732 by Mahesh Chand and David Talbot ' add columns Apress © 2003 (928 pages) custTable.Columns.Add("id", Type.GetType("System.Int32")) custTable.Columns.Add("name", This text provides extensive coverage Type.GetType("System.String")) of ADO.NET technology including ADO.NET internals, namespaces, classes, and custTable.Columns.Add("address", Type.GetType("System.String")) interfaces, and takes a comprehensive look at XML ' add a ColumnChanged & ColumnChanging event handler for the table. namespaces and classes, and how to integrate both with AddHandler custTable.RowChanged, New DataRowChangeEventHandler _ ADO.NET. (AddressOf Row_Changed) AddHandler custTable.RowChanged, New DataRowChangeEventHandler _ Table of(AddressOf Contents Row_Changing) Applied'ADO.NET—Building add Two rows Data-Driven Solutions Introduction custTable.Rows.Add(New Object() {1, "name1", "address1"}) Object() {2, "name2", "address2"}) ChaptercustTable.Rows.Add(New 1 - ADO.NET Basics ' Save changes Chapter 2 - Data Components in Visual Studio .NET ChaptercustTable.AcceptChanges() 3 - ADO.NET in Disconnected Environments Address column in all the rows Chapter'4 change - ADO.NET in Connected Environments Dim row As DataRow Chapter 5 - Handling ADO.NET Events For Each row In custTable.Rows Chapter 6 - Integrating XML with ADO.NET row("name") = "New name" Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Next row Chapter 8 - Constraints and Data Relations ' Removing event handlers Chapter 9 - ADO.NET Exception Handling RemoveHandler custTable.RowChanged, AddressOf Row_Changed Chapter 10 - Working with the ODBC .NET Data Provider RemoveHandler custTable.RowChanging, AddressOf Row_Changing Chapter - Stored Procedures and Views End11Sub Chapter 12 Oracle, SQLXML, Other .NET Data Providers ' Row -Changed eventand handler Chapter 13 - Developing Custom Data Provider Private Shared aSub Row_Changed(ByVal sender As Object, _ Chapter 14 -eDeveloping Database Web Applications using ASP.NET ByVal As DataRowChangeEventArgs) ChapterMessageBox.Show("Row_Changed 15 - Using ADO.NET in Xml Web ServicesEvent:" & _ Chaptere.Row("name", 16 - ASP.NET Server DataRowVersion.Original).ToString() Controls and Data Binding & _ Chaptere.Action.ToString()) 17 - Building Real-World Web Applications End18Sub Chapter - Object-Relational Mapping in .NET ' Row event handlerConsiderations and Data Binding Chapter 19 -Changing Mapped Objects: Performance Private Shared Sub Row_Changing(ByVal sender As Object, _ Chapter 20 - COM Interoperability and ADO.NET ByVal e As DataRowChangeEventArgs) Chapter 21 - Messaging MessageBox.Show("Row_Changing Event:" & _ Chapter 22 - SQL Server and ADO.NET: Notes on Performance e.Row("name", DataRowVersion.Original).ToString() & _ Appendix A - Relational Databases: Some Basic Concepts e.Action.ToString()) Appendix B - Commonly Used SQL Statements End Sub Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables Listing 5-11 creates a DataTable, adds three columns—id, name, and address—adds data to the table, List Listings a column of the table. It also calls the RowDeleting and RowDeleted event handlers. andofchanges List of Sidebars

Listing 5-11: Writing the RowDeleting and RowDeleted Event Handlers ' Row Deleted and Row Deleting Events Caller Private Sub DeleteRow_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles DeleteRow.Click Dim custTable As DataTable = New DataTable("Customers") ' add columns custTable.Columns.Add("id", Type.GetType("System.Int32")) custTable.Columns.Add("name", Type.GetType("System.String")) custTable.Columns.Add("address", Type.GetType("System.String")) ' add a ColumnChanged & ColumnChanging event handler for the table.

AddHandler custTable.RowDeleted, New DataRowChangeEventHandler _ ADO.NET: Building Data-Driven Solutions (AddressOfApplied Row_Deleted) ISBN:1590590732 by Mahesh Chand and David Talbot New DataRowChangeEventHandler AddHandler custTable.RowDeleting, _ Apress © 2003 (928 pages) (AddressOf Row_Deleting) text provides extensive coverage of ADO.NET technology ' add TwoThis rows including ADO.NET internals, namespaces, classes, and custTable.Rows.Add(New Object() {1, "name1", "address1"}) interfaces, and takes a comprehensive look at XML custTable.Rows.Add(New Object() {2, "name2", namespaces and classes, and how to integrate both "address2"}) with ' Save changes ADO.NET. custTable.AcceptChanges() ' change Address column in all the rows Table ofDim Contents row As DataRow Applied'ADO.NET—Building Data-Driven Go through all rows Solutions Introduction For Each row In custTable.Rows Chapter 1 - ADO.NET ' Delete the Basics row Chapter row.Delete() 2 - Data Components in Visual Studio .NET Next Chapter 3 -row ADO.NET in Disconnected Environments ' Removing event handlers Chapter 4 - ADO.NET in Connected Environments RemoveHandler custTable.RowDeleted, AddressOf Row_Deleted Chapter 5 - Handling ADO.NET Events RemoveHandler custTable.RowDeleting, AddressOf Row_Deleting Chapter 6 - Integrating XML with ADO.NET End Sub Chapter 7 - Data Binding and Windows Forms Data-Bound Controls ' Row Deleted event handler Chapter 8 - Constraints and Data Relations Private Shared Sub Row_Deleted(ByVal sender As Object, _ Chapter 9 - ADO.NET Exception Handling ByVal e As DataRowChangeEventArgs) Chapter 10 - Working with the ODBC .NET Data Provider MessageBox.Show("Row_Deleted Event:" & _ Chapter 11 - Stored Procedures and Views e.Row("name", DataRowVersion.Original).ToString() & _ Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers e.Action.ToString()) Chapter 13 - Developing a Custom Data Provider End Sub Chapter - Developing Database Web Applications using ASP.NET 'Row14Deleting event handler Chapter 15 Using ADO.NET in Xml Web Services Private Shared Sub Row_Deleting(ByVal sender As Object, _ Chapter 16 ASP.NET Server Controls and Data Binding ByVal e As DataRowChangeEventArgs) Chapter 17 - Building Real-World Web Applications MessageBox.Show("Row_Deleting Event:" & _ Chapter e.Row("name", 18 - Object-Relational DataRowVersion.Original).ToString() Mapping in .NET & _ e.Action.ToString()) Chapter 19 - Mapped Objects: Performance Considerations and Data Binding End Sub Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions Working with XmlDataDocument Events by Mahesh Chand and David Talbot

ISBN:1590590732

You must be wondering XmlDataDocument comes from. Actually, this class works with Extensible Apress ©where 2003 (928 pages) Markup Language (XML) documents and is defined in System.Xml namespace. So before testing this This text provides extensive coverage ofthe ADO.NET technology example, you must import the System.Xml namespace. (We discuss the XmlDataDocument object in including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Chapter 6.) namespaces and classes, and how to integrate both with

ADO.NET. want to skip this section if you're not familiar with the XmlDataDocument object. Note You might Chapter 6 covers XmlDataDocument. Table of Contents

TheXmlDataDocument events are useful when your application needs to be notified when changes are

Applied ADO.NET—Building Data-Driven Solutions being made to an XmlDataDocument object. XmlDocument defines the XmlDataDocument events (see Introduction Table 5-6). Chapter 1

- ADO.NET Basics

Chapter 2 - XmlDataDocument Data Components in Visual Studio .NET Table 5-6: Events Chapter 3


EVENT Chapter 4 - ADO.NET in DESCRIPTION Connected Environments Chapter 5 - Handling ADO.NET NodeChanged OccursEvents when the Value of a node has been changed Chapter 6 - Integrating XML with ADO.NET

NodeChanging when the Value of a node is changing Chapter 7 - Data BindingOccurs and Windows Forms Data-Bound Controls Chapter 8 - Constraints Occurs and Data Relations NodeInserted when a node inserted into another node Chapter 9 - ADO.NET Exception Handling

NodeInserting Occurs when a node inserting to another node Chapter 10 - Working with the ODBC .NET Data is Provider Chapter 11 - Stored Procedures Views NodeRemoved Occursand when a node has been removed Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

NodeRemoving

Occurs when a node is being removed


Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services TheXmlNodeChangedEventHandler method handles these (NodeChanged,NodeChanging, Chapter 16 - ASP.NET Server Controls and Data Binding and NodeRemoving) events. The NodeInserted, NodeInserting, NodeRemoved, Chapter 17 - Building Real-World Web Applications XmlNodeChangedEventHandler is defined as follows: Chapter 18 - Object-Relational Mapping in .NET Chapter 19 Delegate - Mapped Objects: Performance Considerations and Data Binding Public Sub XmlNodeChangedEventHandler(_ Chapter 20 - COM Interoperability and ADO.NET ByVal sender As Object, _ Chapter 21 - Messaging ByVal e As XmlNodeChangedEventArgs _ Chapter 22 - SQL Server and ADO.NET: Notes on Performance ) Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

In this example, sender is the source of the event and e is an XmlNodeChangedEventArgs containing the Appendix C - ADO.NET Frequently Asked Questions event data. The XmlNodeChangedEventArgs defines properties (see Table 5-7).

Index

List of Figures

Table 5-7: The XmlNodeChangedEventArgs Properties

List of Tables

ListPROPERTY of Listings

DESCRIPTION

List of Sidebars

Action

Returns a value indicating the type of node-changed event

NewParent

Returns the value of parent node after the operation is finished

Node

Returns the node that is being added, removed, or changed

OldParent

Returns the value of the parent node before operation started

Listing 5-12 handles the XmlDataDocument events. The XmlDocumentBtn_Click method creates event handlers for NodeChanged,NodeInserted, and NodeRemoved events. MyNodeChangedEvent, MyNodeInsertedEvent, and MyNodeRemoved event handlers are executed when these events are fired. You use LoadXml to load an XML fragment and then use the ReplaceChild and RemoveChild methods to replace and remove document nodes.

Listing 5-12: TheApplied XmlDataDocument Event Data-Driven Handling Example ADO.NET: Building Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

Apress © 2003 (928 pages) Private Sub XmlDataDocumentBtn_Click(ByVal sender As System.Object, _ ByVal e As This System.EventArgs) text provides extensiveHandles coverage of XmlDataDocumentBtn.Click ADO.NET technology including ADO.NET internals, namespaces, classes, and Dim xmlDoc As XmlDocument = New XmlDocument() interfaces, and takes a comprehensive look at XML xmlDoc.LoadXml(" Some Value ") namespaces and classes, and how to integrate both with ' Add event handlers ADO.NET. AddHandler xmlDoc.NodeChanged, AddressOf NodeChangedEvent_Handler AddHandler xmlDoc.NodeInserted, AddressOf NodeInsertedEvent_Handler Table of Contents AddHandler xmlDoc.NodeRemoved, AddressOf NodeRemovedEvent_Handler AppliedDim ADO.NET—Building Data-Driven Solutions root As XmlElement = xmlDoc.DocumentElement Introduction Dim str As String = root.ToString() As XmlDocumentFragment = xmlDoc.CreateDocumentFragment() ChapterDim 1 -xmlDocFragment ADO.NET Basics xmlDocFragment.InnerXml = _ .NET Chapter 2 - Data Components in Visual Studio "Fragment Data" Chapter 3 - ADO.NET in Disconnected Environments ' Replace Node Chapter 4 - ADO.NET in Connected Environments As XmlElement = xmlDoc.DocumentElement ChapterDim 5 -rootNode Handling ADO.NET Events rootNode.ReplaceChild(xmlDocFragment, rootNode.LastChild) Chapter 6 - Integrating XML with ADO.NET ' Remove Node Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Dim node As XmlNode = xmlDoc.LastChild Chapter 8 - Constraints and Data Relations xmlDoc.RemoveChild(node) Chapter 9 - ADO.NET Exception Handling ' Remove event handlers Chapter 10 - Working with the ODBC .NET Data Provider RemoveHandler xmlDoc.NodeChanged, AddressOf NodeChangedEvent_Handler ChapterRemoveHandler 11 - Stored Procedures and Views xmlDoc.NodeInserted, AddressOf NodeInsertedEvent_Handler ChapterRemoveHandler 12 - Oracle, SQLXML, and Other .NET Data Providers xmlDoc.NodeRemoved, AddressOf NodeRemovedEvent_Handler Chapter - Developing a Custom Data Provider End13Sub Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Listing 17 5-13 shows the NodeChangedEvent handler. The Node property of XmlNodeChangedEventArgs Chapter - Building Real-World Web Applications returns18 an-XmlNode object. Using theinNode Chapter Object-Relational Mapping .NET property you can get more information about a node such as its parent 19 node, value, Objects: name, namespace, so on. (Seeand theData "Using the XmlNode Class" section of Chapter 6 Chapter - Mapped Performanceand Considerations Binding to learn more about XmlNode.)


Listing 5-13: The NodeChanged Event Handler


' NodeChanged event handler Public Sub NodeChangedEvent_Handler(ByVal src As Object, _ Appendix C - ADO.NET Frequently Asked Questions ByVal args As XmlNodeChangedEventArgs) Index MessageBox.Show("Node Changed Event Fired for node " + args.Node.Name) List of Figures If args.Node.Value Nothing Then List of Tables MessageBox.Show(args.Node.Value) List of Listings End If List of Sidebars End Sub Appendix B - Commonly Used SQL Statements

Similar to Listing 5-13,Listing 5-14 and Listing 5-15 show event handlers for the NodeInserted and NodeRemoved events. Listing 5-14: The NodeInserted Event Handler ' NodeInserted event handler Public Sub NodeInsertedEvent_Handler(ByVal src As Object, _ ByVal args As XmlNodeChangedEventArgs)

MessageBox.Show("Node Inserted Event Fired for node " + args.Node.Name) Applied ADO.NET: Building Data-Driven Solutions If args.Node.Value Nothing Then ISBN:1590590732 by Mahesh Chand and David Talbot MessageBox.Show(args.Node.Value) Apress © 2003 (928 pages) End If This text provides extensive coverage of ADO.NET technology End Sub including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Listing 5-15: The NodeRemoved Event Handler Table of Contents

' Node Removed event handler Public Sub NodeRemovedEvent_Handler(ByVal src As Object, _ Introduction ByVal args As XmlNodeChangedEventArgs) Chapter 1 - ADO.NET Basics MessageBox.Show("Node Removed Event Fired for node " + args.Node.Name) Chapter 2 - Data Components in Visual Studio .NET If args.Node.Value Nothing Then Chapter 3 MessageBox.Show(args.Node.Value) - ADO.NET in Disconnected Environments ChapterEnd 4 -If ADO.NET in Connected Environments Chapter 5 End SubHandling ADO.NET Events Applied ADO.NET—Building Data-Driven Solutions

Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions Working with DataView and DataViewManager Events by Mahesh Chand and David Talbot

ISBN:1590590732

TheDataView and DataViewManager objects both define a ListChanged event. The ListChanged event Apress © 2003 (928 pages) occurs when a row is added to or deleted from a DataView or DataViewManager object. The This text provides extensive coverage of ADO.NET technology ListChangedEventHandler method handles the ListChanged event and is defined as follows: including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Public Delegate Sub ListChangedEventHandler(_ ADO.NET.

ByVal sender As Object, _ ByVal e As ListChangedEventArgs _ Table ) of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction

In this example, sender is the source of the event and e is the ListChangedEventArgs containing the event Chapter 1 - ADO.NET Basics data. 2 Chapter


Chapter 3 - ADO.NET in Disconnected Environments TheListChangedEventArgs has the members defined in Table 5-8. Chapter 4 - ADO.NET in Connected Environments Chapter 5 - The Handling ADO.NET Events Table 5-8: ListChangedEventArgs Members Chapter 6 - Integrating XML with ADO.NET

MEMBER DESCRIPTION Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Chapter 8 - Constraints and Data Relations ListChangedType Chapter 9

Returns the way that list changed


NewIndex Returns new index of the item in the list Chapter 10 - Working with the ODBC the .NET Data Provider Chapter 11 - Stored Procedures and Views OldIndex Returns the old index of the item in the list Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter - Developing Custom Data Provider Listing 13 5-16 shows the aOnListChanged_Handler. Chapter 14 - Developing Database Web Applications using ASP.NET

Listing15 5-16: DataView Event Handler Chapter - Using ADO.NET OnListChanged in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 Sub - Building Real-World Web Applications Public OnListChanged_Handler(ByVal src As Object, _ Chapter 18 - Object-Relational Mapping in .NET ByVal args As System.ComponentModel.ListChangedEventArgs) Chapter 19 - Mapped Objects: Performance Considerations Binding MessageBox.Show("ListChanged: Type = "and + Data args.ListChangedType & _ Chapter ",20OldIndex - COM Interoperability = " + args.OldIndex and ADO.NET & _

",21NewIndex Chapter - Messaging= " + args.NewIndex) End Sub Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

To test this application, you can create a Windows application and add the code in Listing 5-17 to the form load event or a button click event handler. As you can see from Listing 5-17, the code creates a DataView object, List of Figures adds a new row to the DataView, and then removes the first row from the DataView. The adding and List of Tables removing of rows is responsible for firing the OnListChanged event handler. Index

List of Listings

List of Sidebars Listing 5-17: The DataView Event Handler Caller

Dim ConnectionString As String = "Integrated Security=SSPI;" & _ "Initial Catalog=Northwind;Data Source=MCB;" Dim conn As SqlConnection = New SqlConnection() conn.ConnectionString = ConnectionString ' Open the connection conn.Open() Dim sql As String = "SELECT EmployeeId, LastName, FirstName FROM Employees" ' Create a data adapter Dim da As SqlDataAdapter = New SqlDataAdapter(sql, conn) ' Create and Fill DataSet

Dim ds As DataSet = New DataSet() Applied ADO.NET: Building Data-Driven Solutions da.Fill(ds, "Employees") ISBN:1590590732 by Mahesh Chand and David Talbot Dim dv As DataView = ds.Tables("Employees").DefaultView Apress © 2003 (928 pages) ' Add DataView Event Handlers text provides extensive coverage of ADO.NET technology AddHandlerThis dv.ListChanged, New System.ComponentModel.ListChangedEventHandler _ including ADO.NET internals, namespaces, classes, and (AddressOf OnListChanged_Handler) interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ' Add a row to the DataView ADO.NET.

dv.AllowEdit = True Dim rw As DataRowView = dv.AddNew() Table rw.BeginEdit() of Contents Applied ADO.NET—Building Data-Driven Solutions rw("FirstName") = "FName" Introduction rw("LastName") = "LName" Chapter 1 - ADO.NET Basics rw.EndEdit() Chapter ' Remove 2 - Data a Components row fromin the VisualDataView Studio .NET If3 dv.Count Then Chapter - ADO.NET > in 0 Disconnected Environments Chapter dv.Delete(0) 4 - ADO.NET in Connected Environments Chapter dv(0).Row.AcceptChanges() 5 - Handling ADO.NET Events End Chapter 6 If - Integrating XML with ADO.NET ' Close the connection Chapter 7 - Data Binding and Windows Forms Data-Bound Controls conn.Close() Chapter 8 - Constraints and Data Relations conn.Dispose() Chapter 9 - ADO.NET Exception Handling ' Remove DataView Event Handlers Chapter 10 - Working with the ODBC .NET Data Provider RemoveHandler dv.ListChanged, AddressOf OnListChanged_Handler Chapter 11 - Stored Procedures and Views

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Caution As you can see from Listing 5-17, the AcceptChanges() method removes a row permanently Chapter 15 - Using ADO.NET in Xml Web Services from the database. If you don't want to remove the row, call RejectChanges instead. Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Summary


ISBN:1590590732

In this chapter, you learned about ADO.NET object events and how to handle them. Events are useful to Apress © 2003 (928 pages) notify an action taken by an object. The Connection has technology two InfoMessage and StateChange This text provides extensive coverage ofobject ADO.NET events. The DataAdapter provides FillError, UpdateChanging, and UpdateChanged events. including ADO.NET internals, namespaces, classes, and takes a comprehensive look at XML TheDataSet hasinterfaces, only one and event—MergeFailed. The DataTable provides events raises during namespaces andXmlDataDocument how to integrate both provides with column and row changes andand rowclasses, deletions. events relating to adding, ADO.NET. changing, and removing XML document nodes. The DataView and DataViewManager define the ListChanged event, which occurs when a row is added to or deleted from a DataView or from a DataViewManager. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

After finishing this chapter, you should have a good idea of the events model of ADO.NET components and how to handle events in your applications.


- ADO.NET Basics

Chapter 2 - Datayou'll Components Visual Studio .NET In next chapter, see howinXML is tied to ADO.NET and how you can take advantage of the ADO.NET Chapter 3 read - ADO.NET Disconnected model to to and in write data from Environments XML documents. Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 6: Integrating XML withISBN:1590590732 ADO.NET by Mahesh Chand and David Talbot Apress (928 pages) The programming world©is2003 moving more and more toward the Web, and Extensible Markup Language This text provides extensive coverage of This ADO.NET technology (XML) is an essential part of Web-based programming. chapter assumes you have an understanding including ADO.NET internals, namespaces, classes, and of basic XML syntaxes and documents. interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with This chapter introduces the classes provided by the .NET Framework Library to work with XML ADO.NET.

documents. In this chapter, we discuss how to read from and write to XML documents using the .NET Framework Library classes. Then we discuss how to navigate through XML documents. We also discuss Table Contents XMLof transformations. Furthermore, this chapter covers the relationship between ADO.NET and XML and Applied shows ADO.NET—Building how to mix them up Data-Driven and use rich Solutions ADO.NET database components to display and manipulate XML data. Finally, we cover the XPathNavigator class, which navigates XML documents. Introduction Chapter 1

- ADO.NET Basics

- Data Components in Visual Studio .NET Understanding Microsoft .NET and XML

Chapter 2 Chapter 3

- ADO.NET in Disconnected Environments Microsoft's Framework utilizes XML features both internally and externally to transfer data between Chapter 4 - .NET ADO.NET in Connected Environments

applications. In the following Chapter 5 - Handling ADO.NETsections, Events you'll learn about the XML namespaces and classes, which you'll use in the throughout chapter. Chapter 6 -examples Integrating XML with this ADO.NET Chapter 7

- Data Binding and Windows Forms Data-Bound Controls In the .NET Framework Library, the System.Xml and its four supporting namespaces define the Chapter 8 - Constraints Data Relations functionality to work withand XML data and documents. These namespaces are System.Xml, Chapter 9 ADO.NET Exception Handling System.Xml.Schema,System.Xml.Serialization,System.Xml.XPath, and Chapter 10 - Working with thenamespaces ODBC .NET Data Provider System.Xml.Xsl. These reside in the System.Xml.dll assembly. Chapter 11 - Stored Procedures and Views

Tip12 Covering classand defined System.Xml and its related namespaces is impossible in this Chapter - Oracle,every SQLXML, Otherin.NET Data Providers chapter. We cover the commonly used classes. If you want to learn more about XML in .NET, you Chapter 13 - Developing a Custom Data Provider can find many useful source samples, articles, and tutorials on C# Corner's XML.NET Chapter 14 - Developing Database Web code Applications using ASP.NET section (www.c-sharpcorner.com/xmlnet.asp ). Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Using the System.Xml Namespace


TheSystem.Xml defines common and major It defines classes for XML Chapter 19 - Mappednamespace Objects: Performance Considerations andXML Data functionality. Binding 1.0, XML and schemas, XPath, XSL Transformations (XSLT), Document Object Model Chapter 20 namespaces - COM Interoperability and ADO.NET (DOM) Level 2 Core, and Simple Object Access Protocol (SOAP) 1.1.


Chapter 22 - SQL Server define and ADO.NET: on Performance The following sections some ofNotes the System.Xml namespace classes. Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements The XmlNode Class Appendix C - ADO.NET Frequently Asked Questions

TheXmlNode class, an abstract base class for XmlDocument and XmlDataDocument, represents a Index single node in a document. This class implements methods for adding, removing, and inserting nodes into List of Figures a document. List of Tables This class also implements properties to get data from a node such as name, child nodes, siblings, parents, and so on.

List of Listings

List of Sidebars

Document Classes TheSystem.Xml namespace also contains classes to deal with XML documents. The XmlDocument andXmlDocumentFragment classes represent an entire XML document and a fragment of document, respectively. The XmlDocumentFragment class is useful when you're dealing with a small fragment of a document. TheXmlDataDocument class allows you to work with relational data using the DataSet object. It provides functionality to store, retrieve, and manipulate data. The XmlDocumentType class represents the type of document. TheXmlDocument and XmlDataDocument classes come from XmlNode. Besides the methods contained in XmlNode, this class implements a series of CreateXXX methods to create a document's

contents such as comments, elements, text, and so on. You can even load an XML document by using its Applied ADO.NET: Building Data-Driven Solutions Load and LoadXml methods. by Mahesh Chand and David Talbot

ISBN:1590590732

2003 document (928 pages) has a corresponding class defined in this namespace. The Each content typeApress of an ©XML classes are XmlAttribute, XmlCDataSection, XmlComment, XmlDeclaration,XmlEntity, This text provides extensive coverage of ADO.NET technology including XmlProcessingInstruction, ADO.NET internals, namespaces, classes, and and XmlWhitespace. All of these XmlEntityReference, XmlText, interfaces, and a comprehensive look at XMLand XmlComment classes represent an classes are self-explanatory. Fortakes example, the XmlAttribute namespaces and classes, and how to integrate both with attribute and comment of a document. You'll see these classes throughout the examples in this chapter. ADO.NET.

Reader and Writer Classes Table of Contents

Six classes (XmlReader,Data-Driven XmlWriter, XmlTextWriter,XmlTextReader,XmlValidatingReader, Applied ADO.NET—Building Solutions andXmlNodeReader) represent the reading and writing of XML documents.

Introduction

Chapter 1 - ADO.NET TheXmlReader and Basics XmlWriter classes are abstract base classes that represent a reader that provides Chapter 2 - Data Components in stream Visual Studio .NET fast, non-cached, forward-only access to XML documents. XmlReader has three classes: Chapter 3 - ADO.NET in Disconnected Environments XmlTextReader, XmlValidatingReader, and XmlNodeReader. As their names imply, Chapter 4 - ADO.NET in Connected XmlTextReader reads text XML Environments documents, XmlNodeReader reads XML DOM trees, and Chapter 5 - Handling ADO.NET Eventsdata using Document Type Definitions (DTDs) or schemas. This XmlValidatingReader validates Chapter reader 6also - Integrating expands general XML with entities ADO.NET and supports default attributes. XmlWriter is an abstract base class Chapter that defines 7 - Data functionality Binding and to write Windows XML.Forms It implements Data-Bound methods Controls and properties to write XML contents. The

XmlTextWriter classand comes the XmlWriter class. Chapter 8 - Constraints Data from Relations Chapter 9


Other10Classes Chapter - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

TheXmlConvert class provides conversion in XML. It defines methods for converting Common Language Runtime (CLR), or .NET data types, and XML Schema Definition (XSD) types. It contains the Chapter 13 - Developing a Custom Data Provider following classes: Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


XmlException defines functionality to represent detailed exceptions. Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

XmlNamespaceManager resolves, adds, and removes namespaces and provides scope management for these namespaces.


Chapter 19 - Mapped Objects: Performance Considerations and DataorBinding XmlLinkedNode returns the node immediately preceding following this node. Chapter 20 - COM Interoperability and ADO.NET

XmlNodeList represents a collection of nodes. Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Using the System.Xml.Schema Namespace


TheSystem.Xml.Schema namespace contains classes to work with XML schemas. These classes Appendix C - ADO.NET Frequently Asked Questions support XML schemas for structures and XML schemas for data types. Index List of Figures

This namespace defines many classes to work with schemas. The discussion of these classes is beyond the scope of this book. Some of these namespace classes are XmlSchema,XmlSchemaAll, List of Listings XmlSchemaXPath, and XmlSchemaType. List of Tables

List of Sidebars

Using the System.Xml.Serialization Namespace This namespace contains classes to serialize objects into XML format documents or streams. Note Serialization is the process of reading and writing an object to or from a persistent storage medium such as a hard drive. You can use the main class, XmlSerializer, with TextWriter or XmlWriter to write the data to a document. Again, this namespace also defines many classes. The discussion of these classes is beyond the scope of this chapter.

Using the System.Xml.XPath Applied ADO.NET: BuildingNamespace Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

This namespace is pretty small in comparison to the previous three namespaces. This namespace Apress © 2003 (928 pages) contains only four classes: XPathDocument,XPathExression,XPathNavigator, and This text provides extensive coverage of ADO.NET technology XPathNodeIterator. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

TheXPathDocument class provides fast XML document processing using the stylesheet language of namespaces and classes, and how to integrate both with XML: XSLT. ThisADO.NET. class is optimized for XSLT processing and the XPath data model. The CreateNavigator method of this class creates an instance of XPathNavigator. TheXPathNavigator class treats an XML document as a tree and provides methods to traverse Table of Contents through a document as tree. Its MoveXXX methods let you traverse through a document. Applied ADO.NET—Building Data-Driven Solutions Introduction

Two other classes of this namespace are XPathExpression and XPathIterator. - ADO.NET Basics XPathExpression encapsulates an XPath expression, and XPathIterator provides an iterator over Chapter 2 - Data Components in Visual Studio .NET the set of selected nodes. Chapter 1 Chapter 3


Chapter 4


Using the System.Xml.Xsl Namespace - Handling ADO.NET Events

Chapter 5 Chapter 6


The last namespace, System.Xml.Xsl, defines functionality for XSLT transformations. It supports XSLT - Data Binding and Windows Forms Data-Bound Controls 1.0. The XsltTransform class defines functionality to transform data using an XSLT stylesheet.

Chapter 7 Chapter 8


Chapter 9


Using the Document Object Model Interfaces


You can represent an XML document in a tree structure using DOM interfaces and objects.


Chapter 13 .NET - Developing Data Provider Microsoft providesa aCustom nice wrapper around these interfaces: the DOM Application Programming Chapter Interface 14 (API). - Developing This wrapper Database hasWeb a class Applications for almost using every ASP.NET interface. These classes hide all the complexity

of interface programming provide a high-level programming model for developers. For example, the Chapter 15 - Using ADO.NETand in Xml Web Services .NET class provides and a wrapper for the Document interface. Chapter 16 - XmlDocument ASP.NET Server Controls Data Binding Chapter 17 - Building Real-World Web Applications

Besides the DOM, the Microsoft .NET XML API also provides corresponding classes for the XPath, XSD, and XSLT industry standards. These classes are well coupled with the .NET database models (ADO.NET) Chapter 19 - Mapped Objects: Performance Considerations and Data Binding to interact with databases. Chapter 18 - Object-Relational Mapping in .NET


Looking at the XML .NET Architecture


The XML .NET API is a nice wrapper around the XML DOM interfaces and provides a higher-level of programming over XML documents. The heart of the XML .NET architecture consists of three classes: Appendix C - ADO.NET Frequently Asked Questions The XmlReader and XmlWriter classes are abstract XmlDocument, XmlReader, and XmlWriter. Index base classes that provide fast, non-cached, forward-only cursors to read and write XML data. List of Figures XmlTextReader, XmlValidatingReader, and XmlNodeReader are concrete implementations of the List of Tables class. The XmlWriter and XmlNodeWriter classes come from the XmlWriter class. XmlReader List XmlDocument of Listings represents an XML document in a tree structure with the help of the XmlNode, XmlElement, List of Sidebars and XmlAttribute classes. Appendix B - Commonly Used SQL Statements

Figure 6-1 shows a relationship between these classes and the XML .NET architecture.


ISBN:1590590732



Figure 6-1: XML .NET architecture


- ADO.NET Basics

TheSystem.Xml.Xsl interface provides classes Chapter 2 - Data Components in Visual Studio .NET that implement XSLT. The XmlTransform class implements XSLT. This class reads and writes XML data with the help of the XmlReader and Chapter 3 - ADO.NET in Disconnected Environments XmlWriter classes. Chapter 4


Chapter 5 - Handling ADO.NET TheXPathDocument and theEvents XPathNavigator classes provide read/write and navigation access to the Chapter 6 Integrating XML with ADO.NET XML documents. Chapter 7


Associated these classes are some more powerful classes for working with XML. We discuss these Chapter 8 - with Constraints and Data Relations classes in "Navigating in XML" and other sections of this chapter. Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

Adding a System.Xml Namespace Reference



Before 13 using the System.Xml in your application, you may need to add a reference to the Chapter - Developing a Customclasses Data Provider System.Xml.dll assembly and include the System.Xml namespace in your application. You can add Chapter 14 - Developing Database Web Applications using ASP.NET

a reference to the System.Xml.dll assembly by selecting Project Ø Add Reference, choosing the .NET tab, and selecting System.Xml.dll from the component name listing. After adding the reference, you need Chapter 16 - ASP.NET Server Controls and Data Binding to import the namespace by adding the following line: Chapter 15 - Using ADO.NET in Xml Web Services


Imports Chapter 19 -System.Xml Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging The abstract base classes XmlReader and XmlWriter support reading and writing XML documents in Chapter 22 Framework. - SQL Server and ADO.NET: Notes on Performance the .NET Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions Reading XML by Mahesh Chand and David Talbot

ISBN:1590590732

As mentioned previously, XmlReader Apress © 2003 (928 pages) is an abstract base class for XML reader classes. This class provides fast, non-cached, forward-only cursors to read XML documents. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

TheXmlTextReader, XmlNodeReader, and XmlValidatingReader classes are defined from the interfaces, and takes a comprehensive look at XML XmlReader class. namespaces Figure 6-2and shows classes, XmlReader and how to and integrate its derived bothclasses. with ADO.NET.


- ADO.NET Basics

Figure and its derived Chapter 2 - 6-2: Data XmlReader Components in Visual Studio classes .NET Chapter 3


Chapter 4 the - ADO.NET in Connected Environments You use XmlTextReader, XmlNodeReader, and XmlValidatingReader classes to read XML Chapter 5 Handling ADO.NET Events documents. These classes define overloaded constructors to read XML files, strings, streams, Chapter 6 - Integrating XML with ADO.NETand combinations of these. After creating an instance, you simply TextReader objects, XmlNameTable, Chapter call the7Read - Data method Binding of and the class Windows to read Forms theData-Bound document.Controls The Read method starts reading the document

from the node and and continues until Read returns False, which indicates there's no node left to read in Chapter 8 root - Constraints Data Relations the document. ListingException 6-1 readsHandling an XML file and displays some information about the file. In this example, Chapter 9 - ADO.NET we use10 thebooks.xml You can use anyProvider XML by replacing the string name. Chapter Working with file. the ODBC .NET Data Chapter 11 - Stored Procedures and Views

Listing 6-1: Reading an XML File


Dim reader As XmlTextReader = New XmlTextReader("C:\\books.xml") Chapter 14 - Developing Database Web Applications using ASP.NET Console.WriteLine("General Chapter 15 - Using ADO.NET in Xml WebInformation") Services Console.WriteLine("===================") Chapter 16 - ASP.NET Server Controls and Data Binding Console.WriteLine(reader.Name) Console.WriteLine(reader.BaseURI) Chapter 18 - Object-Relational Mapping in .NET Console.WriteLine(reader.LocalName) Chapter 17 - Building Real-World Web Applications

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Getting Node Information


TheName property returns the name of the node with the namespace prefix, and the LocalName property returns the name of the node without the prefix.


List ofItem Figures The property works as an indexer and returns the value of the attribute at the specified index. The List of Tables Value property returns the value of current node. You can even get the level of the node by using the List Depth of Listings property, as shown in Listing 6-2. List of Sidebars

Listing 6-2: Getting XML Node Information Dim reader As XmlTextReader = New XmlTextReader("C:\\books.xml") While reader.Read() If reader.HasValue Then Console.WriteLine("Name: "+reader.Name) Console.WriteLine("Node Depth: " +reader.Depth.ToString()) Console.WriteLine("Value: "+reader.Value) End If End While


TheNodeType property by Mahesh returns Chand theand type David of the Talbot current node inISBN:1590590732 the form of an XmlNodeType Apress © 2003 (928 pages) enumeration: This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and XmlNodeType type = reader.NodeType; interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

which defines the type of a node. The XmlNodeType enumeration members are Attribute,CDATA, Comment,Document,Element,WhiteSpace, and so on. These represent XML document node types. Table of Contents

In Listing 6-3, you read a document's one by one and count them. Once the reading and counting Applied ADO.NET—Building Data-Driven nodes Solutions are done, you see how many comments, processing instructions, CDATAs, elements, whitespaces, and so Introduction on that a document has and display them on the console. The XmlReader.NodeType property returns - ADO.NET Basics the type of node in the form of an XmlNodeType enumeration. The XmlNodeType enumeration contains Chapter 2 - Data Components in Visual Studio .NET a member corresponding to each node type. You can compare the return value with the XmlNodeType Chapter 3 - ADO.NET in Disconnected Environments members to find out the node's type. Chapter 1

Chapter 4


Chapter - Handling Events Listing56-3: GettingADO.NET Node Information Chapter 6


Chapter 7


Sub Main() Chapter 8 - Constraints and Data Relations Dim DecCounter As Integer = 0 Chapter 9 - ADO.NET Exception Handling Dim PICounter As Integer = 0 ChapterDim 10 -DocCounter Working with the .NET Data AsODBC Integer = 0Provider ChapterDim 11 -CommentCounter Stored Procedures and Views As Integer = 0 ChapterDim 12 -ElementCounter Oracle, SQLXML, and As Other .NET Data=Providers Integer 0 ChapterDim 13 -AttributeCounter Developing a Custom Data As Provider Integer = 0 ChapterDim 14 -TextCounter Developing Database Web Applications As Integer = 0 using ASP.NET ChapterDim 15 -WhitespaceCounter Using ADO.NET in Xml Web AsServices Integer = 0 As XmlTextReader New XmlTextReader("C:\\books.xml") ChapterDim 16 -reader ASP.NET Server Controls and Data=Binding reader.Read() ChapterWhile 17 - Building Real-World Web Applications Dim nodetype AsMapping XmlNodeType = reader.NodeType Chapter 18 - Object-Relational in .NET Select Case nodetype Chapter 19 - Mapped Objects: Performance Considerations and Data Binding XmlNodeType.XmlDeclaration Chapter 20 -Case COM Interoperability and ADO.NET DecCounter = DecCounter + 1 Chapter 21 - Messaging Exit Select Chapter 22 - SQL Server and ADO.NET: Notes on Performance Case XmlNodeType.ProcessingInstruction Appendix A - Relational Databases: Some Basic Concepts PICounter = PICounter + 1 Appendix B - Commonly Used SQL Statements Exit Select Appendix C - ADO.NET Frequently Asked Questions Case XmlNodeType.DocumentType Index DocCounter = DocCounter + 1 List of Figures Exit Select List of TablesCase XmlNodeType.Comment List of Listings CommentCounter = CommentCounter + 1 List of Sidebars Exit Select Case XmlNodeType.Element ElementCounter = ElementCounter + 1 If reader.HasAttributes Then AttributeCounter += reader.AttributeCount End If Exit Select Case XmlNodeType.Text TextCounter = TextCounter + 1 Exit Select Case XmlNodeType.Whitespace WhitespaceCounter = WhitespaceCounter + 1

Exit Select Applied ADO.NET: Building Data-Driven Solutions End Select ISBN:1590590732 End Whileby Mahesh Chand and David Talbot Apress © 2003 (928 pages) ' Print the info This text provides extensive coverage+of WhitespaceCounter.ToString()) ADO.NET technology Console.WriteLine("White Spaces:" including ADO.NET internals, namespaces, classes, Console.WriteLine("Process Instructions:" + and PICounter.ToString()) interfaces, and takes a comprehensive look at XML Console.WriteLine("Declaration:" DecCounter.ToString()) namespaces and classes, and how to+ integrate both with Console.WriteLine("White Spaces:" + DocCounter.ToString()) ADO.NET. Console.WriteLine("Comments:" + CommentCounter.ToString()) Console.WriteLine("Attributes:" + AttributeCounter.ToString()) TableEnd of Contents Sub Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

TheCase can haveinthe values XmlNodeType.XmlDeclaration, Chapter 2 statement - Data Components Visual Studio .NET XmlNodeType.ProcessingInstruction, XmlNodeType.DocumentType, Chapter 3 - ADO.NET in Disconnected Environments XmlNodeType.Comment, XmlNodeType.Element, XmlNodeType.Text, Chapter 4 - ADO.NET in Connected Environments XmlNodeType.Whitespace , and so on. Chapter 5 - Handling ADO.NET Events Chapter 6

- Integrating XML with ADO.NET TheXmlNodeType enumeration specifies the type of node. Table 6-1 describes its members.

Chapter 7


Chapter 8 - The Constraints and DataEnumeration's Relations Table 6-1: XmlNodeType Members Chapter 9 - ADO.NET Exception Handling

MEMBER Chapter 10 - NAME Working with the ODBC DESCRIPTION .NET Data Provider Chapter 11 - Stored Procedures and Views

Attribute

Attribute node


CDATA CDATA section Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Comment

Comment node


Document Document Chapter 16 - ASP.NET Server Controls and Data object Binding Chapter 17 - Building Real-World Web Applications DocumentFragment Document fragment Chapter 18 - Object-Relational Mapping in .NET

DocumentType The DTD, indicated byand theData tag Chapter 19 - Mapped Objects: Performance Considerations Binding Chapter 20 - COM Interoperability and ADO.NET Element Element node Chapter 21 - Messaging

EndNotes of element Chapter 22 - SQL Server and ADO.NET: on Performance EndElement

Appendix A - Relational Databases: Some Basic Concepts EndEntity End of an entity Appendix B - Commonly Used SQL Statements

Entity

Entity declaration

Appendix C - ADO.NET Frequently Asked Questions Index EntityReference List of Figures

None

List of Tables ListNotation of Listings List of Sidebars

Reference to an entity Returned if XmlReader is not called yet A notation in the document type

ProcessingInstruction

Represents a processing instruction (PI) node

SignificantWhitespace

Represents whitespace between markup in a mixed content model

Text

Represents the text content of an element

Whitespace

Represents whitespace between markup

XmlDeclaration

Represents an XML declaration node

Moving to a Content Node

You can use the MoveToMethod to move from the current node to the next content node of an XML Applied ADO.NET: Building Data-Driven Solutions document. A content's node is an item of the following type: Text,CDATA,Element, ISBN:1590590732 by Mahesh Chand and David Talbot EntityReference, or Entity. So, if you call the MoveToContent method, it skips other types of Apress © 2003 (928 pages) nodes besides the content type nodes. For example, if the next node of the current node is PI, This text provides extensive coverage of ADO.NET technology DxlDeclaration, orincluding DocumentType, it'll skip these nodes until it finds a content type node. Listing 6-4 reads ADO.NET internals, namespaces, classes, and books.xml and interfaces, moves through its using the MoveToContent method. and takesnodes a comprehensive look at XML namespaces and classes, and how to integrate both with

Listing 6-4: Using the MoveToContent Method ADO.NET. Dim ofreader As XmlTextReader = New XmlTextReader("C:\\books.xml") Table Contents reader.Read() AppliedWhile ADO.NET—Building Data-Driven Solutions Console.WriteLine(reader.Name) reader.MoveToContent() Chapter 1 - ADO.NET Basics Console.WriteLine(reader.Name) Chapter 2 - Data Components in Visual Studio .NET End While Introduction

Chapter 3


Chapter 4


Chapter 5


Chapter 6


Using the a Data-Bound Node Controls - DataGetAttributes Binding and Windows of Forms

Chapter 7 Chapter 8


TheGetAttribute method is an overloaded method. You can use this method to return attributes with - ADO.NET Exception Handling the specified name, index, local name, or namespace Uniform Resource Indicator (URI). You use the Chapter 10 - Working with the ODBC .NET Data Provider HasAttributes property to check if a node has attributes, and AttributeCount returns the number Chapter 11 - Stored Procedures and Views of attributes on the node. The local name is the name of the current node without prefixes. For example, if Chapter 12 - Oracle, SQLXML, and Other .NET where Data Providers represents a name of a node, bk is a namespace and : refers to the namespace, the Chapter 13 - for Developing a Custom element Data Provider local name the is book.MoveToFirstAttribute moves to the first attribute. Chapter 14 - Developing method Databasemoves Web Applications usingthat ASP.NET TheMoveToElement to the element contains the current attribute node (see Listing Chapter 6-5). 15 - Using ADO.NET in Xml Web Services Chapter 9


Listing17 6-5: Using the GetAttribute of a Node Chapter - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 -System.Xml Mapped Objects: Performance Considerations and Data Binding Imports Chapter Module 20 Module1 - COM Interoperability and ADO.NET

Sub21Main() Chapter - Messaging Asand XmlTextReader = Performance _ ChapterDim 22 -reader SQL Server ADO.NET: Notes on New Appendix A -XmlTextReader("C:\\books.xml") Relational Databases: Some Basic Concepts reader.MoveToContent() Appendix B - Commonly Used SQL Statements reader.MoveToFirstAttribute() Appendix C - ADO.NET Frequently Asked Questions Console.WriteLine("First Attribute Value" + reader.Value) Console.WriteLine("First Attribute Name" + reader.Name) List of Figures While reader.Read() List of Tables If reader.HasAttributes Then List of Listings Console.WriteLine(reader.Name + " Attribute") List of Sidebars Dim i As Integer Dim counter As Integer = reader.AttributeCount - 1 For i = 0 To counter reader.MoveToAttribute(i) Console.WriteLine("Name: " + reader.Name) Next i reader.MoveToElement() End If End While End Sub End Module Index

Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 You can move toby attributes Mahesh by Chand using and MoveToAttribute, David Talbot MoveToFirstAttribute, and MoveToNextAttribute. Apress © 2003 MoveToFirstAttribute (928 pages) and MoveToNextAttribute move to the first and next attributes, respectively. After callingcoverage MoveToAttribute, the Name,Namespace, and Prefix This text provides extensive of ADO.NET technology including ADO.NET internals, namespaces, classes, and properties will reflect the properties of the specified attribute.


Searching for a Node

TheSkip method skips the current node. It's useful when you're looking for a particular node and want to Table Contents skip of other nodes. In Listing 6-6, you read the books.xml document and compare its XmlReader.name Applied ADO.NET—Building Data-Driven (throughXmlTextReader) to look forSolutions a node with the name bookstore and display the name, level, and Introduction value of that node using XmlReader'sName,Depth, and Value properties. Chapter 1 - ADO.NET Basics

Listing26-6: Using the Skip in Method Chapter - Data Components Visual Studio .NET Chapter 3


Chapter 4 - ADO.NET in Connected Environments New XmlTextReader("C:\\books.xml") ChapterWhile 5 - Handling ADO.NET Events reader.Read() Chapter 6 ' -Look Integrating for XML a node with ADO.NET with name bookstore

reader.Name "bookstore" Then Controls Chapter 7 If- Data Binding and Windows Forms Data-Bound -reader.Skip() Constraints and Data Relations Else Chapter 9 - ADO.NET Exception Handling " + reader.Name) Chapter 10 -Console.WriteLine("Name: Working with the ODBC .NET Data Provider Console.WriteLine("Level of the node: " + reader.Depth.ToString()) Chapter 11 - Stored Procedures and Views Console.WriteLine("Value: " + reader.Value) Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers End If Chapter 13 - Developing a Custom Data Provider End While Chapter 14 - Developing Database Web Applications using ASP.NET reader.Close() Chapter 8



Closing the Document


Finally, you use Close to close the opened XML document.


Chapter SQL 6-3 Server and ADO.NET: Notes onclass Performance Tables22 6-2- and describe the XmlReader properties and methods. We already discussed some Appendix A Relational Databases: Some Basic Concepts of them in the previous discussion. Appendix B - Commonly Used SQL Statements Appendix Table 6-2: C - The ADO.NET XmlReader Frequently Class Asked Properties Questions Index List of Figures List of Tables List of Listings List of Sidebars

PUBLIC INSTANCE DESCRIPTION Applied ADO.NET: Building Data-Driven Solutions PROPERTY ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

AttributeCount BaseURI Depth

Returns the number of attributes on the current node

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Returns the base URI of the current node interfaces, and takes a comprehensive look at XML namespaces andReturns classes,the andlevel howof to the integrate with currentboth node ADO.NET.

Indicates whether its pointer is at the end of the stream

EOF HasAttributes Table of Contents

Indicates if a node has attributes

Applied ADO.NET—Building Data-Driven Solutions HasValue Indicates if a node has a value Introduction

Indicates whether the current node is an attribute generated from the default value Chapter 2 - Data Components in Visual Studio .NETdefined in the DTD or schema Chapter 3 - ADO.NET in Disconnected Environments IsEmptyTag Returns if the current node is empty or not IsDefault Chapter 1 - ADO.NET Basics

Chapter 4


Chapter 5


Item

Returns the value of the attribute

Chapter 6 - Integrating XML with Name ADO.NET LocalName of the current node without the namespace prefix Chapter 7 - Data Binding and Windows Forms Data-Bound Controls

Name

Chapter 8

Name of the current node with the namespace prefix


Chapter NamespaceURI 9 - ADO.NET Exception Handling Namespace Uniform Resource Name (URN) of the current Chapter 10 - Working with the ODBC namespace .NET Datascope Provider Chapter 11 - Stored Procedures and Views

NameTable

Returns the XmlNameTable associated with this implementation


NodeType the type of node Chapter 13 - Developing a CustomReturns Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Prefix

Returns the namespace associated with a node


ReadState Read state Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Value

Returns the text value of a node


XmlLang Returns the current xml:lang Chapter 19 - Mapped Objects: Performance Considerations and Datascope Binding Chapter 20 - COM Interoperability Returns and ADO.NET XmlSpace the current xml:space scope Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - The Relational Databases: Some Basic Concepts Table 6-3: XmlReader Class Methods Appendix B - Commonly Used SQL Statements

PUBLIC METHODAsked Questions DESCRIPTION Appendix C - INSTANCE ADO.NET Frequently Index Close List of Figures

Closes the stream and changes ReadState to Closed


Returns the value of an attribute

ListIsStartElement of Sidebars

Checks if a node has start tag

GetAttribute

LookupNamespace

Resolves a namespace prefix in the current element's scope

MoveToAttribute,MoveToContent, MoveToElement

Moves to specified attribute, content, and element

MoveToFirstAttribute, MoveToNextAttribute

Moves to the first and next attributes

Read

Reads a node

ReadAttributeValue Parses theSolutions attribute value into one or more Text Applied ADO.NET: Building Data-Driven and/or EntityReference ISBN:1590590732 node types by Mahesh Chand and David Talbot Apress ©ReadBoolean, 2003 (928 pages) ReadXXX (ReadChar, Reads the contents of an element into the This text extensive coverage of ADO.NET technology ReadDate,ReadInt32,provides and so on) specified type including char, integer, double, including ADO.NET internals, namespaces, classes, and string, date, and so on interfaces, and takes a comprehensive look at XML

to integrate with as a string ReadInnerXmlnamespaces and classes, and howReads all theboth content ADO.NET.

Skips the current element

Skip Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Appliedthe ADO.NET: Building Data-Driven Understanding XmlWriter Classes Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

As you saw in theApress "Understanding Microsoft .NET and XML" section, the XmlWriter class contains © 2003 (928 pages) methods and properties to write to XML documents, XmlTextWriter This text provides extensive coverageand of ADO.NET technology and XmlNodeWriter come from the XmlWriter class. Figure 6-3 shows XmlWriter and its derived classes. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


Figure 6-3: TheXmlWriter class and its derived classes

Chapter 1

- ADO.NET Basics

Chapter 2


Chapter Besides3 providing - ADO.NET a constructor in Disconnected and three Environments properties (WriteState,XmlLang, and XmlSpace), the

XmlWriter classes in have many WriteXXX methods to write to XML documents. The following sections Chapter 4 - ADO.NET Connected Environments discuss5some of these class methods Chapter - Handling ADO.NET Events and properties and use them in examples of the XmlTextWriter andXmlNodeWriter creates a write object and writes to the documents. The Chapter 6 - Integrating classes. XML withXmlTextWriter ADO.NET XmlTextWriter constructor can take threeData-Bound types of inputs: a string, stream, or TextWriter. Chapter 7 - Data Binding and Windows Forms Controls Chapter 8


Exception Handling Setting- ADO.NET XmlWriter Properties

Chapter 9


TheXmlWriter contains three properties: WriteState,XmlLang, and XmlSpace. The Chapter 11 - Storedclass Procedures and Views WriteState property gets the state of the XmlWriter class. The values could be Attribute, Chapter 12 - Oracle, SQLXML, and current Other .NET Data Providers

Start,Element,Content,Closed, or Prolog. The return value WriteState.Start means the Write method has not been called yet. In other cases, it represents what's being written. For example, the Chapter 14 - Developing Database Web Applications using ASP.NET return value WriteState.Attribute means the Attribute value has been written. Chapter 15 - Using ADO.NET in Xml Web Services WriteState.Close represents that the stream has been closed by calling Close method. Chapter 13 - Developing a Custom Data Provider


Writing XML Items

Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

As discussed earlier, an XML document can have many types of items including elements, comments, attributes, and whitespaces. Although it's not possible to describe all the WriteXXX methods here, we Chapter 21 - Messaging cover the most important ones. Chapter 20 - COM Interoperability and ADO.NET


Appendix TheWriteStartDocument A - Relational Databases: andSome WriteEndDocument Basic Concepts methods open and close a document for writing,

respectively. You mustUsed openSQL a document before you start writing to it. The WriteComment method writes Appendix B - Commonly Statements comments a document. It takes onlyQuestions one string type: argument. The WriteString method writes a Appendix C - to ADO.NET Frequently Asked string to a document. With the help of WriteString, you can use the WriteStartElement and Index WriteEndElement method pair to write an element to a document. The WriteStartAttribute and List of Figures WriteEndAttribute pair writes an attribute. WriteNode is another write method, which writes List of Tables XmlReader to a document as a node of the document.

List of Listings

List of Sidebars

The following example summarizes these methods and creates a new XML document with some items in it such as elements, attributes, strings, comments, and so on. (See Listing 6-7 in the next section.) Listing 6-7: XmlWriter Example Imports System.Xml Module Module1 Sub Main() ' Create a new file c:\xmlWriterTest.xml Dim writer As XmlTextWriter = _ New XmlTextWriter("C:\\xmlWriterTest.xml", Nothing) ' Opens the document

writer.WriteStartDocument() Applied ADO.NET: Building Data-Driven Solutions ' Write comments ISBN:1590590732 by Mahesh Chand and David Talbot uses XmlTextWriter.") writer.WriteComment("This program Apress © 2003 (928 pages) writer.WriteComment("Developed By: Mahesh Chand.") This text provides extensive coverage of ADO.NET technology writer.WriteComment("================================") includingelement ADO.NET internals, namespaces, classes, and ' Write first interfaces, and takes a comprehensive look at XML writer.WriteStartElement("root") namespaces and classes, and how to integrate both with writer.WriteStartElement("r", "RECORD", "urn:record") ADO.NET. ' Write next element writer.WriteStartElement("FirstName", "") Table ofwriter.WriteString("Mahesh") Contents Appliedwriter.WriteEndElement() ADO.NET—Building Data-Driven Solutions Introduction ' Write one more element Chapterwriter.WriteStartElement("LastName", 1 - ADO.NET Basics "") Chapterwriter.WriteString("Chand") 2 - Data Components in Visual Studio .NET Chapterwriter.WriteEndElement() 3 - ADO.NET in Disconnected Environments an inXmlTextReader to read books.xml Chapter'4 Create - ADO.NET Connected Environments XmlTextReader = New XmlTextReader("c:\\books.xml") ChapterDim 5 -reader Handling As ADO.NET Events reader.Read() ChapterWhile 6 - Integrating XML with ADO.NET reader.NodeType = XmlNodeType.Element Chapter 7 If- Data Binding and Windows Forms Data-Bound Controls Then ' Add node.xml to xmlWriterTest.xml usign WriteNode Chapter 8 - Constraints and Data Relations writer.WriteNode(reader, True) Chapter 9 - ADO.NET Exception Handling End If Chapter 10 - Working with the ODBC .NET Data Provider End While Chapter 11 - Stored Procedures and Views ' Ends the document. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers writer.WriteEndDocument() Chapterwriter.Close() 13 - Developing a Custom Data Provider Chapter - Developing Database Web Applications using ASP.NET End14Sub Chapter 15 - Using ADO.NET in Xml Web Services End Module Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

In this example, youObjects: create aPerformance new XML file, c:\xmlWriterText.xml, Chapter 19 - Mapped Considerations and Data Binding using XmlTextWriter: Chapter 20 - COM Interoperability and ADO.NET Chapter ' Create 21 - Messaging a new file c:\xmlWriterTest.xml

Asand XmlTextWriter = Performance _ ChapterDim 22 -writer SQL Server ADO.NET: Notes on New Nothing) Appendix A -XmlTextWriter("C:\\xmlWriterTest.xml", Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

After that, add comments and elements to the document using WriteXXX methods. After that you can read the books.xml file using XmlTextReader and add its elements to xmlWriterTest.xml using List of Figures XmlTextWriter: Index


' Create an XmlTextReader to read books.xml Dim reader As XmlTextReader = New XmlTextReader("c:\\books.xml") While reader.Read() If reader.NodeType = XmlNodeType.Element Then ' Add node.xml to xmlWriterTest.xml usign WriteNode writer.WriteNode(reader, True) End If End While

List of Sidebars

Seeing XmlWriter in Action Listing 6-7 shows an example of using XmlWriter to create a new document and write its items. This

program creates a new XML document, xmlWriterTest, in the C:\ root directory. Applied ADO.NET: Building Data-Driven Solutions

ISBN:1590590732 by6-7, Mahesh Chand and David Note In Listing you write output of theTalbot program to a file. If you want to write your output directly on Apresspass © 2003 (928 pages) the console, Console.Out as the filename when you create an XmlTextWriter object. For example: This text XmlTextWriter provides extensivewriter coverage=of new ADO.NET XmlTextWriter technology (Console.Out); .

including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look atthe XML When you open C: \xmlWriterTest.xml in a browser, output of the program looks like Listing 6-8. namespaces and classes, and how to integrate both with ADO.NET. Listing 6-8: Output of the XmlWriterSample.vb Class Table of Contents Applied ADO.NET—Building Data-Driven Solutions -

Developed Chapter-1 .NET - Data Components in Visual Studio 4 - ADO.NET in Connected Environments Chapter-5 - Handling ADO.NET Events - Chapter 6 - Integrating XML with ADO.NET Mahesh Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Chand Chapter 8 - Constraints and Data Relations - Chapter 9 - ADO.NET Exception Handling - Chapter 10 - Working with the ODBC .NET Data Provider The Autobiography of Benjamin Franklin Chapter-11 - Stored Procedures and Views ChapterBenjamin 12 - Oracle, SQLXML, and Other .NET Data Providers ChapterFranklin 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter8.99 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter-17 - Building Real-World Web Applications The Confidence Chapter 18 - Object-Relational MappingMan in .NET Chapter-19 - Mapped Objects: Performance Considerations and Data Binding ChapterHerman 20 - COM Interoperability and ADO.NET ChapterMelville 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance 11.99 Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements - Appendix C - ADO.NET Frequently Asked Questions The Gorgias Index - List of Figures Plato List of Tables List of Listings 9.99 List of Sidebars Chapter 2

Using the Close Method You use the Close method when you're done with the XmlWriter object to close the stream.

Applied ADO.NET:Class Building Data-Driven Solutions Using the XmlConvert by Mahesh Chand and David Talbot

ISBN:1590590732

Some charactersApress aren't ©valid XML documents. XML documents use XSD types, which are different from 2003in (928 pages) CLR (.NET) dataThis types. The XmlConvert contains methods to convert from CLR types to XSD text provides extensiveclass coverage of ADO.NET technology types and vice versa. The DecodeName method transfers an XML name into an ADO.NET object such as including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look XML aDataTable. The EncodeName method is the reverse of at DecodeName: It converts an ADO.NET object namespaces and how to integrate both with an escape string. Another method, to a valid XSD name. It takes and any classes, invalid character and replaces it with ADO.NET. EncodeLocalName, converts unpermitted names to valid names. Besides these three methods, the XmlConvert class has many methods to convert from a string object to Boolean, byte, integer, and so on. Listing 6-9 shows the conversion from a Boolean and DateTime Applied ADO.NET—Building Data-Driven Solutions object to XML values.


Chapter - ADO.NET Basics Listing16-9: Using the XmlConvert Class Chapter 2 - Data Components in Visual Studio .NET Chapter 3


Dim writer As XmlTextWriter = _ - ADO.NET in Connected Environments New XmlTextWriter("c:\\test.xml", Nothing) Chapter 5 - Handling ADO.NET Events writer.WriteStartElement("MyTestElements") ChapterDim 6 -bl Integrating XML with As Boolean = ADO.NET True Chapterwriter.WriteElementString("TestBoolean", 7 - Data Binding and Windows Forms Data-Bound Controls _ ChapterXmlConvert.ToString(bl)) 8 - Constraints and Data Relations ChapterDim 9 -dt ADO.NET Exception Handling As DateTime = New DateTime(2000, 1, 1) Chapterwriter.WriteElementString("TestDate", 10 - Working with the ODBC .NET Data Provider _ ChapterXmlConvert.ToString(dt)) 11 - Stored Procedures and Views Chapterwriter.WriteEndElement() 12 - Oracle, SQLXML, and Other .NET Data Providers writer.Flush() Chapter 13 - Developing a Custom Data Provider Chapterwriter.Close() 14 - Developing Database Web Applications using ASP.NET Chapter 4

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Appliedthe ADO.NET: Data-Driven Solutions Understanding DOMBuilding Implementation by Mahesh Chand and David Talbot

ISBN:1590590732

Microsoft .NET supports DOM Level 1 and DOM Level 2 Core specifications. The .NET Apress ©the 2003W3C (928 pages) Framework provides DOM implementation many classes;technology XmlNode and XmlDocument are two of This text provides extensivethrough coverage of ADO.NET them. Using these two classes, you can easily traverse through XML including ADO.NET internals, namespaces, classes, anddocuments in the same manner as you do in a tree. interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Using the XmlNode Class

Table of Contents TheXmlNode class is an abstract base class; it represents a node of an XML document. Because an XML Applied document ADO.NET—Building starts with a root Data-Driven node, theSolutions XmlNode class that corresponds to the root node represents the

entire XML document's nodes. An XmlNode object can represent a node at any level. This class defines Introduction enough1 methods andBasics properties to represent a document node as a tree node and traverse though it. It also Chapter - ADO.NET provides to insert, replace, remove Chapter 2 methods - Data Components in Visualand Studio .NETdocument nodes. Chapter 3


TheChildNodes property returns all the child nodes of the current node. You can treat an entire - ADO.NET in Connected Environments document as a node and use ChildNodes to get all the nodes in a document. Also, you can use the Chapter 5 - Handling ADO.NET Events FirstChild,LastChild, and HasChildNodes triplet to traverse from a document's first node to the Chapter 6 -The Integrating XML with ADO.NET last node. ParentNode, PreviousSibling, and NextSibling properties return the parent and Chapter 7 Data Binding and Windows Forms Data-Bound Controlsproperties are Attributes, BaseURI, previous/next sibling nodes of the current node. Other common Chapter 8 - Constraints and DataNodeType, Relations Name, Value, and so on. InnerXml, InnerText, Item, Chapter 4

Chapter 9

- ADO.NET Exception Handling You can the CreateNavigator of this class to create an XPathNavigator object, which Chapter 10use - Working with the ODBC .NETmethod Data Provider

provides navigation using and XPath. The AppendChild,InsertAfter, and InsertBefore methods Chapter 11fast - Stored Procedures Views add nodes the document. TheOther RemoveAll, RemoveChild, and ReplaceChild methods remove or Chapter 12 - to Oracle, SQLXML, and .NET Data Providers replace13 document nodes, respectively. You'll implement these methods and properties later in this chapter. Chapter - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Using the XmlDocument Class



TheXmlDocument class represents an XML document. Because it's derived from the XmlNode class, it supports all tree traversal, insert, remove, and replace functionality. In spite of XmlNode functionality, this Chapter 18 - Object-Relational Mapping in .NET class contains many useful methods. Chapter 17 - Building Real-World Web Applications


Chapter 20 -isCOM Interoperability and ADO.NET The DOM a cached tree representation of an XML document. The Load and LoadXml methods of this Chapter 21 -XML Messaging class load data and documents, and the Save method saves a document. Chapter 22 - SQL Server and ADO.NET: Notes on Performance

TheLoad canDatabases: load a document fromConcepts a string, stream, TextReader, or XmlReader. The following Appendix A method - Relational Some Basic code loads document books.xml from a string: Appendix B - the Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Dim xmlDoc As XmlDocument = New XmlDocument() Index Dim filename As String = "C:\\books.xml" List of Figures xmlDoc.Load(filename) List of Tables xmlDoc.Save(Console.Out) List of Listings List of Sidebars

The following example uses the Load method to load a document from an XmlReader: Dim xmlDoc As XmlDocument = New XmlDocument() Dim reader As XmlTextReader _ = New XmlTextReader("C:\\books.xml") xmlDoc.Load(reader) xmlDoc.Save(Console.Out)

TheLoadXml method loads a document from the specified string. For example:

Applied ADO.NET: Building Data-Driven Solutions xmlDoc.LoadXml(" write something"); by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

This text provides extensive coverage of ADO.NET technology Saving a Document including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

TheSave methodnamespaces saves a document to a and specified Save and classes, how tolocation. integrateThe both with method takes a parameter of ADO.NET. XmlWriter,XmlTextWriter, or a string type: Dim Table of xmlDoc Contents As XmlDocument = New XmlDocument() Dim filename As String = "C:\\books.xml" Applied ADO.NET—Building Data-Driven Solutions xmlDoc.Load(filename) Dim writer As XmlTextWriter = _ Chapter 1 - ADO.NET Basics New XmlTextWriter("C:\\domtest.xml", Nothing) Chapter 2 - Data Components in Visual Studio .NET writer.Formatting = Formatting.Indented Chapter 3 - ADO.NET in Disconnected Environments xmlDoc.Save(writer) Introduction

Chapter 4


Chapter 5


Chapter You can 6 also - Integrating use a filename XML with or Console.Out ADO.NET to save the output as a file or on the console: Chapter 7


Chapter 8 - Constraints and Data Relations xmlDoc.Save("C:\\domtest.xml") Chapter 9 - ADO.NET Exception Handling xmlDoc.Save(Console.Out) Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Using the XmlDocumentFragment Class


Chapter 14you - Developing Web Applications using class ASP.NET Usually, would useDatabase the XmlDocumentFragment when you need to insert a small fragment of an Chapter XML document 15 - Using orADO.NET node intoinaXml document. Web Services This class also comes from the XMLNode class and has the same Chapter tree node 16 traverse, - ASP.NETinsert, Serverremove, Controlsand and replace Data Binding capabilities. Chapter 17 - Building Real-World Web Applications

You usually create this class instance by calling XmlDocument'sCreateDocumentFragment method. TheInnerXml property represents the children of this node. Listing 6-10 shows an example of how to Chapter 19 - Mapped Objects: Performance Considerations and Data Binding create XmlDocumentFragment and load a small piece of XML data using its InnerXml property. Chapter 18 - Object-Relational Mapping in .NET


Chapter - Messaging Listing21 6-10: The XmlDocumentFragment Sample Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Dim xmlDoc As XmlDocument = New XmlDocument() Dim filename As String = "C:\\books.xml" Appendix C - ADO.NET Frequently Asked Questions xmlDoc.Load(filename) Index 'Create a document fragment. List of Figures Dim docFrag As XmlDocumentFragment = xmlDoc.CreateDocumentFragment() List of Tables 'Set the contents of the document fragment. List of Listings docFrag.InnerXml = " write something" List of Sidebars 'Display the document fragment. Console.WriteLine(docFrag.InnerXml) Appendix B - Commonly Used SQL Statements

You can use XmlNode methods to add, remove, and replace data. Listing 6-11 appends a node in the document fragment. Listing 6-11: Appending in an XML Document Fragment Dim doc As XmlDocument = New XmlDocument() doc.LoadXml("" & _

"ADO.NET Programming" & _ Applied ADO.NET: Building Data-Driven Solutions "") ISBN:1590590732 by Mahesh ' Get the root node Chand and David Talbot Apress © 2003 (928 pages) Dim root As XmlNode = doc.DocumentElement Thisnode. text provides extensive coverage of ADO.NET technology ' Create a new including ADO.NET internals, namespaces, classes, and Dim newbook As XmlElement = doc.CreateElement("price") interfaces, and takes a comprehensive look at XML newbook.InnerText = "44.95" namespaces and classes, and how to integrate both with 'Add the nodeADO.NET. to the document. root.AppendChild(newbook) doc.Save(Console.Out) Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Using the XmlElement Class Chapter 2 - Data Components in Visual Studio .NET Chapter 3 - ADO.NET in object Disconnected Environments AnXmlElement class represents an element in a document. This class inherits from the Chapter 4 ADO.NET in Connected Environments XmlLinkedNode class, which inherits from the XmlNode, as shown in Figure 6-4. Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure TheXmlElement class inheritance Chapter 22 - 6-4: SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

TheXmlLinkedNode has two useful properties: NextSibling and PreviousSibling. As their names indicate, these properties return the next and previous nodes of an XML document's current node.


The class implements and overrides some useful methods for adding and removing List ofXmlElement Figures attributes and elements. Table 6-4 describes some of the XmlElement class methods. List of Tables List of Listings

Table 6-4: Some XmlElement Class Methods List of Sidebars

METHOD

DESCRIPTION Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Returns the attribute value Apress © 2003 (928 pages)

GetAttribute

ISBN:1590590732

HasAttributeThis text provides Checks extensive if a node coverage has the of ADO.NET specifiedtechnology attribute including ADO.NET internals, namespaces, classes, and all the children and attributes of the current node interfaces, and Removes takes a comprehensive look at XML namespaces and classes, and how to integrate both with RemoveAllAttributes Removes all attributes from an element ADO.NET.

RemoveAll

RemoveAttribute Table of Contents RemoveAttributeAt

Removes specified attributes from an element Removes the attribute node with the specified index from the attribute

Applied ADO.NET—Building Data-Driven Solutions collection Introduction

RemoveAttributeNode Chapter 1 - ADO.NET Basics

Removes an XmlAttribute

Chapter 2 - Data Components in Sets Visual Studio SetAttribute the value.NET of the specified attribute Chapter 3 - ADO.NET in Disconnected Environments

SetAttributeNode Adds a new XmlAttribute - ADO.NET in Connected Environments

Chapter 4 Chapter 5


In the later- examples, we show you how you can use these methods in your programs to get and set XML Integrating XML with ADO.NET element attributes.

Chapter 6 Chapter 7


Chapter 8

Constraints and Data Relations Adding -Nodes to a Document

Chapter 9


Chapter 10use - Working with the ODBC .NET Data Provider You can the AppendChild method to add a node to an existing document. The AppendChild Chapter method11takes - Stored a single Procedures parameter and of Views XmlNode type. The XmlDocument'sCreateXXX methods can create

different of nodes. For and example, the CreateComment and CreateElement methods create Chapter 12types - Oracle, SQLXML, Other .NET Data Providers comment elementanode types. Listing 6-12 shows an example of adding two nodes to a document. Chapter 13 and - Developing Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Listing 6-12: Adding Nodes to a Document


Dim xmlDoc As Real-World XmlDocument = New XmlDocument() Chapter 17 - Building Web Applications xmlDoc.LoadXml(" Some Value ") Chapter 18 - Object-Relational Mapping in .NET ' Adding a new Objects: comment node toConsiderations the document Chapter 19 - Mapped Performance and Data Binding Dim node1 As Interoperability XmlNode = xmlDoc.CreateComment("DOM Testing Sample") Chapter 20 - COM and ADO.NET xmlDoc.AppendChild(node1) ' Adding an FirstName to the document Chapter 22 - SQL Server and ADO.NET: Notes on Performance node1 = xmlDoc.CreateElement("FirstName") Appendix A - Relational Databases: Some Basic Concepts node1.InnerText = "Mahesh" Appendix B - Commonly Used SQL Statements xmlDoc.DocumentElement.AppendChild(node1) Appendix C - ADO.NET Frequently Asked Questions xmlDoc.Save(Console.Out) Chapter 21 - Messaging

Index List of Figures List of Tables List of Listings Getting the

Root Node

List of Sidebars

TheDocumentElement method of the XmlDocument class (inherited from XmlNode) returns the root node of a document. Listing 6-13 shows you how to get the root node of a document. Listing 6-13: Getting the Root Node of a Document Dim filename As String = "C:\\books.xml" Dim xmlDoc As XmlDocument = New XmlDocument() xmlDoc.Load(filename) Dim root As XmlElement = xmlDoc.DocumentElement

Removing and Replacing Nodes Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

TheRemoveAll method of the XmlNode class can remove all elements and attributes of a node. Apress © 2003 (928 pages) RemoveChild removes the specified child only. Listing 6-14 calls RemoveAll to remove all the elements This text provides extensive coverage of ADO.NET technology and attributes of aincluding node. ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

Listing 6-14: Removing All Items of a Node namespaces and classes, and how to integrate both with ADO.NET.

' Load a document fragment xmlDoc As XmlDocument = New XmlDocument() Table Dim of Contents xmlDoc.LoadXml("" & _ Applied ADO.NET—Building Data-Driven Solutions "ADO.NET Programming ") Introduction Dim root As XmlNode = xmlDoc.DocumentElement Chapter 1 - ADO.NET Basics Console.WriteLine("XML Document Fragment") Chapter 2 - Data Components in Visual Studio .NET Console.WriteLine("=====================") Chapter 3


Chapter 4

- ADO.NET in Connected Environments xmlDoc.Save(Console.Out)

Chapter 5 - Handling ADO.NET Events Console.WriteLine() Chapter 6 - Integrating XML with ADO.NET Console.WriteLine("---------------------") Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Console.WriteLine("XML Document Fragment After RemoveAll") Chapter 8 - Constraints and Data Relations Console.WriteLine("=====================") Chapter 9 - ADO.NET Exception Handling 'Remove all attribute and child nodes. Chapter root.RemoveAll() 10 - Working with the ODBC .NET Data Provider

' Display contents on the console after Chapter 11 - Storedthe Procedures and Views ' removing elements Chapter 12 - Oracle, SQLXML, and and Otherattributes .NET Data Providers xmlDoc.Save(Console.Out) Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Note You can apply the RemoveAll method on the books.xml file to delete all the data, but make sure to have a backup copy first!


Chapter - Mapped Objects: Performance Considerations and Data Binding Listing 19 6-15 shows how to delete all the items of books.xml. Chapter 20 - COM Interoperability and ADO.NET

Listing21 6-15: CallingRemoveAll for books.xml Chapter - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Basic Concepts Dim filename As Databases: String =Some "C:\\books.xml" Appendix B - Commonly Used SQL Statements Dim xmlDoc As XmlDocument = New XmlDocument() Appendix xmlDoc.Load(filename) C - ADO.NET Frequently Asked Questions Index

Dim root As XmlNode = xmlDoc.DocumentElement List of Figures Console.WriteLine("XML Document Fragment") List of Tables Console.WriteLine("=====================") List of Listings List of Sidebars

xmlDoc.Save(Console.Out) Console.WriteLine() Console.WriteLine("---------------------") Console.WriteLine("XML Document Fragment After RemoveAll") Console.WriteLine("=====================") 'Remove all attribute and child nodes. root.RemoveAll() ' Display the contents on the console after ' removing elements and attributes xmlDoc.Save(Console.Out)

Applied ADO.NET: Building Data-Driven Solutions TheReplaceChild method replaces an old child with a new child node. In Listing 6-16,ReplaceChild ISBN:1590590732 replacesrootNode.LastChild by Mahesh Chand with and David xmlDocFrag. Talbot Apress © 2003 (928 pages)

Listing 6-16: Calling ReplaceChild This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Dim filename namespaces As String "C:\\books.xml" and= classes, and how to integrate both with Dim xmlDocADO.NET. As XmlDocument = New XmlDocument()

xmlDoc.Load(filename) Dim root As XmlElement = xmlDoc.DocumentElement Table Dim of Contents xmlDocFragment As XmlDocumentFragment = xmlDoc.CreateDocumentFragment() Applied ADO.NET—Building Data-Driven Solutions xmlDocFragment.InnerXml = _ Introduction "Fragment Data" Chapter 1 rootNode - ADO.NET Basics Dim As XmlElement = xmlDoc.DocumentElement Chapter 'Replace 2 - Data xmlDocFragment Components in Visualwith Studio rootNode.LastChild .NET rootNode.ReplaceChild(xmlDocFragment, rootNode.LastChild) Chapter 3 - ADO.NET in Disconnected Environments xmlDoc.Save(Console.Out) Chapter 4 - ADO.NET in Connected Environments Chapter 5


Chapter 6


Chapter 7


Chapter 9


Inserting XML Fragments into an XML Document Chapter 8 - Constraints and Data Relations

As discussed previously, the XmlNode class is useful for navigating through a document's nodes. It also provides other methods to insert XML fragments into a document. For instance, the InsertAfter method Chapter 11 - Stored Procedures and Views inserts a document or element after the current node. This method takes two arguments. The first Chapter 12 -isOracle, SQLXML, and Other .NETobject, Data Providers argument an XmlDocumentFragment and the second argument is the position where you want Chapter 13the - Developing a Custom Dataearlier Provider to insert fragment. As discussed in this chapter, you create an XmlDocumentFragment class Chapter 14 using - Developing Database Web Applications using ASP.NET object by the CreateDocumentFragment method of the XmlDocument class. Listing 6-17 inserts Chapter - Using ADO.NET in Xml Web an XML15fragment into a document afterServices the current node using InsertAfter. Chapter 10 - Working with the ODBC .NET Data Provider


Listing17 6-17: Inserting an XML Fragment into a Document Chapter - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Dim xmlDoc As XmlDocument = New XmlDocument() ChapterxmlDoc.Load("c:\\books.xml") 20 - COM Interoperability and ADO.NET

As XmlDocumentFragment = _ ChapterDim 21 -xmlDocFragment Messaging ChapterxmlDoc.CreateDocumentFragment() 22 - SQL Server and ADO.NET: Notes on Performance

xmlDocFragment.InnerXml _ Concepts Appendix A - Relational Databases: Some = Basic "Fragment Data" Appendix B - Commonly Used SQL Statements Dim AsFrequently XmlNode = xmlDoc.DocumentElement.FirstChild Appendix C -aNode ADO.NET Asked Questions Index

aNode.InsertAfter(xmlDocFragment, aNode.LastChild) xmlDoc.Save(Console.Out)



Adding Attributes to a Node You use the SetAttributeNode method of XmlElement to add attributes to an element, which is a node.XmlAttribute represents an XML attribute. You create an instance of XmlAttribute by calling CreateAttribute of XmlDocument. After that you call an XmlElement'sSetAttribute method to set the attribute of an element. Finally, you append this new item to the document (see Listing 6-18). Listing 6-18: Adding a Node with Attributes Dim xmlDoc As XmlDocument = New XmlDocument() xmlDoc.Load("c:\\books.xml") Dim NewElem As XmlElement = xmlDoc.CreateElement("NewElement")

Dim NewAttr As XmlAttribute = xmlDoc.CreateAttribute("NewAttribute") Applied ADO.NET: Building Data-Driven Solutions NewElem.SetAttributeNode(NewAttr) ISBN:1590590732 Mahesh Chand and Talbot 'add the by new element to David the document Apress © 2003 (928 pages) Dim root As XmlElement = xmlDoc.DocumentElement This text provides extensive coverage of ADO.NET technology root.AppendChild(NewElem) including ADO.NET internals, namespaces, classes, and xmlDoc.Save(Console.Out) interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



AppliedTransformation ADO.NET: Building Data-Driven Solutions Understanding and XSLT by Mahesh Chand and David Talbot

ISBN:1590590732

Extensible Stylesheet Language Apress © 2003 (928(XSL) pages) is a language for expressing stylesheets. Stylesheets format XML documents in a way so that the XML data can be presented in a certain structure in a browser or other This text provides extensive coverage of ADO.NET technology media such as catalogs, books, and so on. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both The XML stylesheet processor reads an XML document (called an with XML sourcetree) and stylesheet, and it ADO.NET. presents the document data in an XML tree format. This processing is XSLT (see Figure 6-5). Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7 - 6-5: Data The Binding Windows Forms Data-Bound Controls Figure XSLand transformation Chapter 8 - Constraints and Data Relations

The result generated after Handling the XML transformation contains element and attribute nodes. In this tree, Chapter 9 -tree ADO.NET Exception an object an XML with element, and properties attribute-value pairs. Chapter 10 is - Working the ODBC .NET Data are Provider Chapter 11 - Stored Procedures and Views

The XSL stylesheet plays a vital role in the XSLT process. A stylesheet contains a set of tree construction

Chapter 12 - Oracle, SQLXML, .NET Providers rules, which have two parts. and TheOther first part is Data a pattern of elements in the source tree, and the second is a Chapter 13 for - Developing a Custom Data parser Provider template the result tree. The XSL reads the pattern and elements from the source tree and then Chapter 14 -results Developing Database Web Applications using ASP.NET generates according to the result tree template. Chapter 15 - Using ADO.NET in Xml Web Services

Transformation is required youand need to Binding convert an XML document into an XML schema-matching Chapter 16 - ASP.NET Server when Controls Data document. XslTransform class provides the functionality to implement the XSLT specification. A Chapter 17 - The Building Real-World Web Applications

separate namespace called System.Xml.Xsl defines this class. Make sure you add a reference to this namespace before using the XslTransform class. You can use the XsltException class to handle Chapter 19 - Mapped Objects: Performance Considerations and Data Binding exceptions thrown by an XSLT transformation. Chapter 18 - Object-Relational Mapping in .NET


Using the Transform Method


TheTransform method of XslTransform transforms data using the loaded stylesheet and outputs the result depending on the argument. This method has eight overloaded forms. You can write output of Appendix C - ADO.NET Frequently Asked Questions Transform in the form of XmlWriter, a stream, TextWriter, or XPathNavigator. (We discuss Index XPathNavigator in the "Navigating in XML" section of this chapter.) Appendix B - Commonly Used SQL Statements

List of Figures

List of Tables Follow these steps perform the transformation: List of 1.Listings First, you need to create an XslTransform object: List of Sidebars

Dim xslt As XslTransform =

New XslTransform()

2. Now, you load the stylesheet using the Load method: xslt.Load("stylesheetFrmt.xsl");

3. Finally, call the Transform method of XslTransform: xslt.Transform("xmlfile.xml", "file.html")

3.

Applied ADO.NET: Building Data-Driven Solutions Chand and David Talbot Looking at by anMahesh Example Apress © 2003 (928 pages)

ISBN:1590590732

This text providesinextensive coverageyou of ADO.NET technology Before you use XslTransform your application, need to add three namespace references to your including ADO.NET internals, namespaces, classes, and application. These namespaces are System.Xml,System.Xml.XPath, and System.Xml.Xsl. (We interfaces, and takes a comprehensive look at XML discuss the XPath namespace more detail in the in XML" namespaces andinclasses, and how to "Navigating integrate both with section of this chapter.) Listing 619 uses the books.xsl ADO.NET.schema file that comes with the .NET Software Development Kit (SDK) samples.

Listing 6-19: An XSL Transformation Table of Contents Applied ADO.NET—Building Data-Driven Solutions

'Create a new XslTransform object and load the stylesheet Dim xslt As XslTransform = New XslTransform() Chapter 1 - ADO.NET Basics xslt.Load("c:\\books.xsl") Chapter 2 - Data Components in Visual Studio 'Create a new XPathDocument and.NET load the XML data to be transformed. Chapter - ADO.NET Disconnected Environments Dim3 mydata As inXPathDocument = New XPathDocument("c:\\books.xml") Chapter 4 - ADO.NET in Connected Environments 'Create an XmlTextWriter which outputs to the console. Chapter - Handling Events= New XmlTextWriter(Console.Out) Dim5 writer AsADO.NET XmlWriter Chapter 6 - Integrating with ADO.NET 'Transform the XML data and send the output to the console. Chapter xslt.Transform(mydata, 7 - Data Binding and Windows Nothing, Forms Data-Bound writer)Controls Introduction

Chapter 8


Chapter 9



Applied and ADO.NET: Building Data-Driven Solutions Using ADO.NET XML Together by Mahesh Chand and David Talbot

ISBN:1590590732

So far in this chapter, you've how to work with XML documents. In this section, you'll now learn how Apress © 2003seen (928 pages) to work with XMLThis documents with the help ofcoverage ADO.NET. There are two approaches to work with XML and text provides extensive of ADO.NET technology ADO.NET. Usingincluding the first approach, you can directly read XML documents by using a DataSet's ADO.NET internals, namespaces, classes, and interfaces, and takes comprehensive look at XMLyou can also update and save XML methods. Not only can you read XML adocuments in a DataSet, namespaces and classes, to integrate withis defined in the System.Data documents by using a DataSet. Besidesand the how DataSet object,both which ADO.NET. namespace, the System.Xml namespace defines classes that can integrate ADO.NET components with XML. In this section, you'll see both of these approaches. Table of Contents

Reading XML Using a DataSet


In ADO.NET, you canBasics access the data using the DataSet class. The DataSet class implements Chapter 1 - ADO.NET methods properties to work with XML documents. Chapter 2 and - Data Components in Visual Studio .NET Chapter 3


Using4 the ReadXML Method Chapter - ADO.NET in Connected Environments Chapter 5

ADO.NET Events ReadXml -isHandling an overloaded method; you can use it to read a data stream, TextReader,XmlReader, or

Chapter with an XML6 file- Integrating and to storeXML data in aADO.NET DataSet object, which can later be used to display the data in a tabular Chapter 7 Data Binding and Windows Forms Data-Bound Controls format. The ReadXml method has eight overloaded forms that can accept the Stream,String, Chapter 8 - Constraints and Data TextReader, XmlReader typesRelations of objects as the first parameter; the second argument is of type Chapter 9 - ADO.NET Exception Handling XmlReadMode. Chapter 10 - Working with the ODBC .NET Data Provider

TheXmlReadMode parameterand defines Chapter 11 - Stored Procedures Viewsthe read mode with these objects. The read mode is of type XmlReadMode. XmlReadMode how to read XML data and a relational schema into a DataSet. Chapter 12 - Oracle, SQLXML, and specifies Other .NET Data Providers Table 6-5 describes the XmlReadMode members.



Table 6-5: The XmlReadMode Members

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding MEMBER DESCRIPTION Chapter 17 - Building Real-World Web Applications

Auto This is Mapping the default mode. It automatically sets the best-suited mode. For Chapter 18 - Object-Relational in .NET

example, If the data is a DiffGram, it sets XmlReadMode to DiffGram. If theDataSet already has a schema, or the document contains an inline Chapter 20 - COM Interoperability and ADO.NET schema, it sets XmlReadMode to ReadSchema. If the DataSet doesn't Chapter 21 - Messaging already have a schema and the document does not contain an inline Chapter 22 - SQL Server and ADO.NET: Notes on Performance schema, it sets XmlReadMode to InferSchema. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding


DiffGram a DiffGram. Appendix B - CommonlyReads Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Fragment Index ListIgnoreSchema of Figures List of Tables ListInferSchema of Listings List of Sidebars

ReadSchema

Reads an XML fragment.

Ignores any inline schema. If any data doesn't match the existing schema, it's discarded. If the DataSet already contains a schema, the current schema is extended by adding new tables or adding columns to existing tables. Reads an XML schema.

Note SeeChapter 3 and Chapter 4 for more details about the DataSet object. In the following example, create a new DataSet object and call the DataSet.ReadXml method to load thebooks.xml file in a DataSet object: ' Create a DataSet Object Dim ds As DataSet = New DataSet() ' Fill with the data

ds.ReadXml("books.xml ") Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

Once you have aApress DataSet © 2003 object, (928 pages) you know how powerful it is. Make sure you provide the correct path to books.xml. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look atand XMLthe System.Data.Common namespace Note Make sure you add a reference to System.Data namespaces and and classes, and how to integrate both with before using DataSet other common data components. ADO.NET.

Using the ReadXmlSchema Method Table of Contents

TheReadXmlSchema method reads an XML schema in a DataSet object. It has four overloaded forms. You can use a TextReader, string, stream, and XmlReader. The following example shows how to use a Introduction file as direct input and call the ReadXmlSchema method to read the file: Applied ADO.NET—Building Data-Driven Solutions Chapter 1

- ADO.NET Basics

Chapter 2


Dim ds As DataSet = New DataSet() - ADO.NET in Disconnected Environments ds.ReadXmlSchema("c:\\books.xml")

Chapter 3 Chapter 4


Chapter 5


Chapter 6 - Integrating with The following example XML reads theADO.NET file XmlTextReader and uses XmlTextReader as the input of Chapter 7 Data Binding and Windows Forms Data-Bound Controls ReadXmlSchema: Chapter 8


Chapter 9 - ADO.NET Exception Handling ' Create a dataset object Chapter 10 As - Working with the ODBC .NET Data Provider Dim ds DataSet = New DataSet("New DataSet") Chapter 11 xsl - Stored and Views ' Read in Procedures an XmlTextReader Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Dim myXmlReader As XmlTextReader = New XmlTextReader("c:\\books.xml") Chapter 13 ReadXmlSchema - Developing a Custom Data Provider ' Call Chapter ds.ReadXmlSchema(myXmlReader) 14 - Developing Database Web Applications using ASP.NET

myXmlReader.Close() Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

Writing XML Using a DataSet



Not only reading, the DataSet contains methods to write XML files from a DataSet object and Chapter 20for - COM Interoperability andclass ADO.NET fill the data the file. Chapter 21 - to Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Using Athe WriteXml Method Appendix - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

TheWriteXml method writes the current data (the schema and data) of a DataSet object to an XML

Appendix C - ADO.NET Frequently Asked Questions file. By using this method, you can write data to a file, stream, TextWriter, or XmlWriter. The Index WriteXml method takes an argument of type Stream,String,TextWriter, or XmlWriter. List of Figures

When writing XML using WriteXml , you can also specify the write mode. The second parameter of List of Tables WriteXml List of Listingsis a type of XmlWriteMode, which specifies the write mode. XmlWriteMode specifies how to write XML data and a relational schema from a DataSet.Table 6-6 describes the XmlWriteMode List of Sidebars members. Table 6-6: The XmlWriteMode Members

MEMBER


DiffGram

ISBN:1590590732 by Mahesh Chand and David Talbot Writes a DataSet's contents including original and current values as a Apress © 2003 (928 pages)

DiffGram.

This text provides extensive coverage of ADO.NET technology ADO.NET internals, namespaces, classes, IgnoreSchemaincluding Writes the current contents of a DataSet asand XML data, without an XSD interfaces, andIftakes a comprehensive look at XML schema. there's no data in a DataSet, nothing is written. namespaces and classes, and how to integrate both with WriteSchema ADO.NET. This is the default mode. The method writes the current contents as XML Table of Contents

data with the relational structure as inline XSD schema. If the DataSet has only a schema with no data, only the inline schema is written. If there's no data in a DataSet, nothing is written.


Chapter - ADO.NET Listing 16-20 creates aBasics DataSet, fills the data for the DataSet, and writes the data to an XML file using Chapter 2 - Data Components in Visual Studio .NET theWriteXml method. Chapter 3


Listing46-20: Using the WriteXml Method Chapter - ADO.NET in Connected Environments Chapter 5


Chapter 6 -System.Data Integrating XML with ADO.NET Imports Chapter 7 -System.Xml Data Binding and Windows Forms Data-Bound Controls Imports Chapter 8 -System.IO Constraints and Data Relations Imports Chapter 9


Module Chapter 10 Module1 - Working with the ODBC .NET Data Provider Sub11Main() Chapter - Stored Procedures and Views Chaptertry 12 - Oracle, SQLXML, and Other .NET Data Providers

Create a DataSet, namespace Chapter'13 - Developing a Custom Data Provider and Student table Name and Address columns using ASP.NET Chapter'with 14 - Developing Database Web Applications Dim ds As DataSet = New DataSet("DS") ds.Namespace = "StdNamespace" Chapter 16 - ASP.NET Server Controls and Data Binding Dim stdTable As DataTable = New DataTable("Student") Chapter 17 - Building Real-World Web Applications Dim col1 As DataColumn = New DataColumn("Name") Chapter 18 - Object-Relational Mapping in .NET Dim col2 As DataColumn = New DataColumn("Address") Chapter 19 - Mapped Objects: Performance Considerations and Data Binding stdTable.Columns.Add(col1) ChapterstdTable.Columns.Add(col2) 20 - COM Interoperability and ADO.NET Chapterds.Tables.Add(stdTable) 21 - Messaging Chapter'22 - SQL Server and ADO.NET: Notes on Performance Add Student Data to the table Appendix A Relational Databases: Some Basic Concepts Dim NewRow As DataRow = stdTable.NewRow() Appendix B - Commonly Used SQL Statements Talmadge" NewRow("Name") = "Melanie Appendix NewRow("Address") C - ADO.NET Frequently=Asked "Meadowlake Questions Dr, Dtown" Index stdTable.Rows.Add(NewRow) NewRow = stdTable.NewRow() List of Figures NewRow("Name") = "Amy Talmadge" List of Tables NewRow("Address") = "Herndon" List of Listings stdTable.Rows.Add(NewRow) List of Sidebars ds.AcceptChanges() ' Create a new StreamWriter ' We'll save data in stdData.xml file Dim writer As System.IO.StreamWriter = _ New System.IO.StreamWriter("c:\\stdData.xml") ' Writer data to DataSet which actually creates the file ds.WriteXml(writer) writer.Close() Catch exp As Exception Console.WriteLine("Exception: {0}", exp.ToString()) End Try End Sub Chapter 15 - Using ADO.NET in Xml Web Services

End Module Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

You wouldn't believe This what text provides the WriteXml extensive method coverage does of ADO.NET for you. Take technology a peek at the output stdData.xml namespaces, file; it generates aincluding standardADO.NET XML fileinternals, that looks like Listing classes, 6-21. and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Listing 6-21: WriteXml Method Output ADO.NET.

- - Applied ADO.NET—Building Data-Driven Solutions Melanie Talmadge Introduction Meadowlake Dr, Dtown Chapter 1 - ADO.NET Basics Chapter 2 - Data Components in Visual Studio .NET - Chapter 3 - ADO.NET in Disconnected Environments Amy Talmadge Chapter Herndon 4 - ADO.NET in Connected Environments Chapter 5 - Handling ADO.NET Events 6 - Integrating XML with ADO.NET Chapter

Table of Contents

Chapter 7


Chapter 8


Chapter 9


Using10the WriteXmlSchema Method Chapter - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

TheWriteXmlSchema method writes a DataSet structure to an XML schema. WriteXmlSchema has four overloaded methods. You can write the data to a stream, text, TextWriter, or XmlWriter.Listing Chapter 13 -XmlWriter Developing afor Custom Data Provider 6-22 uses the output. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter Listing15 6-22: - Using Using ADO.NET the WriteXmlSchema in Xml Web Services Method Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 As - Building Real-World Applications Dim ds DataSet = NewWeb DataSet("DS") Chapter 18 - Object-Relational Mapping in .NET ds.Namespace = "StdNamespace" Chapter 19 - Mapped Performance Considerations and Data Binding Dim stdTable AsObjects: DataTable = New DataTable("Students") Chapter 20 - COM Interoperability = and ADO.NET Dim col1 As DataColumn New DataColumn("Name") Chapter 21 - Messaging Dim col2 As DataColumn = New DataColumn("Address") Chapter stdTable.Columns.Add(col1) 22 - SQL Server and ADO.NET: Notes on Performance

stdTable.Columns.Add(col2) Appendix A - Relational Databases: Some Basic Concepts ds.Tables.Add(stdTable) Appendix B - Commonly Used SQL Statements ' Add C Student Data to the table Appendix - ADO.NET Frequently Asked Questions Dim NewRow As DataRow = stdTable.NewRow() Index NewRow("Name") = "Melnaie Talmadge" List of Figures NewRow("Address") = "Meadowlake Dr, Dtown" stdTable.Rows.Add(NewRow) List of Listings NewRow = stdTable.NewRow() List of Sidebars NewRow("Name") = "Amy Talmadge" NewRow("Address") = "Herndon, VA" stdTable.Rows.Add(NewRow) ds.AcceptChanges() Dim writer As XmlTextWriter = New XmlTextWriter(Console.Out) ds.WriteXmlSchema(writer) List of Tables

Refer to the previous section to see how to create an XmlTextWriter object.

Using XmlDataDocument andData-Driven XML Applied ADO.NET: Building Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

As discussed earlier in this chapter, the XmlDocument class provides a DOM tree structure of XML Apress © 2003 (928 pages) documents. The XmlDataDocument class comes from XmlDocument, which comes from XmlNode. provides extensiveclass coverage of ADO.NET technology Figure 6-6 showsThis the text XmlDataDocument inheritance. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6

Integrating XML with ADO.NET Figure- 6-6: TheXmlDataDocument class inheritance

Chapter 7


Chapter 8

- Constraints and Data Relations Besides9 overriding theException methodsHandling of XmlNode and XmlDocument,XmlDataDocument also implements its Chapter - ADO.NET

own methods. The XmlDataDocument classProvider lets you load relational data using the DataSet object as Chapter 10 - Working with the ODBC .NET Data well as XML documents using the Load and LoadXml methods. As Figure 6-7 indicates, you can use a DataSet to load relational data to an XmlDataDocument object and use the Load or LoadXml Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers methods to load an XML document. Figure 6-7 shows the relationship between a Reader,Writer, Chapter 13 - Developing a Custom Data Provider DataSet, and XmlDataDocument. Chapter 11 - Stored Procedures and Views

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix Figure B - 6-7: Commonly Reading Used and SQL writing Statements data using XmlDataDocument Appendix C - ADO.NET Frequently Asked Questions

TheXmlDataDocument class extends the functionality of XmlDocument and synchronizes it with a Index

DataSet. As you know, a DataSet is a powerful object in ADO.NET. As Figure 6-7 shows, you can take data from two different sources. First, you can load data from an XML document with the help of List of Tables XmlReader, and second, you can load data from relational data sources with the help of database List of Listings providers and a DataSet. The neat thing is the data synchronization between these two objects. If you List of Sidebars update data in a DataSet object, you see the results in the XmlDataDocument object-and vice versa. For example, if you add a record to a DataSet object, the action will add one node to the XmlDataDocument object representing the newly added record. List of Figures

Once the data is loaded, you're allowed to use any operations that you're able to use on XmlDocument objects. You can also use XmlReader and XmlWriter objects to read and write the data. TheXmlDataDocument class has a property called DataSet. It returns the attached DataSet object with XmlDataDocument. The DataSet property provides you a relational representation of an XML document. Once you have a DataSet object, you can do anything with it that you did in Chapters 3 and 4, such as binding it to data-bound controls. You can use all the XML read and write methods of the DataSet object (such as ReadXml,

ReadXmlSchema,WriteXml, and WriteXmlSchema) through the DataSet property. Refer to the Applied ADO.NET: Data-Driven DataSet read and write methods in Building the previous section toSolutions see how these methods are used.

Loading

by Mahesh Chand and David Talbot © 2003 (928 pages) DataApress Using Load and LoadXml

ISBN:1590590732

from the XmlDataDocument

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and an XML document. The Load You can use either the Load method or the LoadXml method to load interfaces, of and a comprehensive look at XMLor an XmlReader. Similarly, you can use method takes a parameter a takes filename string, a TextReader, namespaces and classes, and how to integrate both with theLoadXml method. This method passes an XML filename to load the XML file. For example: ADO.NET.

Dim doc As XmlDataDocument = New XmlDataDocument() Table of Contents doc.Load("C:\\Books.xml") Applied ADO.NET—Building Data-Driven Solutions Introduction

Or you 1can- load an XML fragment, as in the following example: Chapter ADO.NET Basics Chapter 2


Chapter 3 -As ADO.NET in Disconnected Environments Dim doc XmlDataDocument = New XmlDataDocument() Chapter doc.LoadXml(" 4 - ADO.NET in Connected write Environments something") Chapter 5


Chapter 6


- Data Binding and Windows Forms Data-Bound Controls Loading Data Using a DataSet

Chapter 7 Chapter 8

- Constraints and Data Relations As you 9learned in Chapter 3, a Handling DataSet object has methods to read XML documents. These methods Chapter - ADO.NET Exception

areReadXmlSchema andthe LoadXml. You useProvider the Load or LoadXml methods to load an XML document Chapter 10 - Working with ODBC .NET Data the same you did directly and fromViews XMLDataDocument. Again, the Load method takes a parameter of a Chapter 11 way - Stored Procedures filename TextReader, XmlReader. Chapter 12string, - Oracle, SQLXML, andorOther .NET DataSimilarly, Providersuse the LoadXml method to pass an XML filename the DataSet. Chapter 13through - Developing a Custom For Dataexample: Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Dim doc XmlDataDocument New XmlDataDocument() Chapter 15 -As Using ADO.NET in Xml Web=Services doc.DataSet.ReadXmlSchema("test.xsd") Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

or as follows:


doc.DataSet.ReadXml(" write something")



Displaying XML Data in a DataSet Format


As mentioned previously, you can get a DataSet object from an XmlDataDocument object by using its DataSet property. OK, now it's time to see how to do that. The next sample shows you how easy it is to List of Tables display an XML document data in a DataSet format. List of Figures

List of Listings

List You of can Sidebars read an XML document using the ReadXml method of the DataSet object. The DataSet

property of XmlDataDocument represents the DataSet of XmlDataDocument. After reading a document in a DataSet, you can create data views from the DataSet, or you can also use a DataSet's DefaultViewManager property to bind to data-bound controls, as you can see in the following code: Dim xmlDatadoc As XmlDataDocument = New XmlDataDocument() xmlDatadoc.DataSet.ReadXml("C:\\XmlDataDoc.xml") dataGrid1.DataSource = xmlDatadoc.DataSet.DefaultViewManager

As you can see from Listing 6-23, you create a new DataSet,Books, fill it from the books.xml file, and bind it to a DataGrid control using its DataSource property. To make Listing 6-23 work, you need to

create a Windows application and drag a DataGrid control to the form. After doing that, write the Listing ADO.NET: Building Data-Driven Solutions 6-23 code on theApplied form load event. by Mahesh Chand and David Talbot

ISBN:1590590732

Apress © 2003 (928 pages) Listing 6-23: XmlDataDocumentSample.vb This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Private Sub Form1_Load(ByVal sender As System.Object, _ interfaces, and takes a comprehensive look at XML ByVal e As namespaces System.EventArgs) Handles MyBase.Load and classes, and how to integrate both with ' Create ADO.NET. an XmlDataDocument object and read an XML

Dim xmlDatadoc As XmlDataDocument = New XmlDataDocument() xmlDatadoc.DataSet.ReadXml("C:\\books.xml") Table of Contents ' Create a DataSet object and fill it with the dataset Applied ADO.NET—Building Data-Driven Solutions ' of XmlDataDocument Introduction Dim ds As DataSet = New DataSet("Books DataSet") Chapterds 1 =- ADO.NET Basics xmlDatadoc.DataSet Chapter'2 Attach - Data Components in Visual dataset view toStudio the .NET DataGrid control ChapterDataGrid1.DataSource 3 - ADO.NET in Disconnected = Environments ds.DefaultViewManager Chapter 4 - ADO.NET in Connected Environments End Sub Chapter 5


Chapter 6


Chapter 7


If you run program,and you'll seeRelations the DataGrid filled with the data. Chapter 8 this - Constraints Data Chapter 9


Saving Data from a DataSet to XML


You can a DataSet asand an Other XML document the Save method of the XmlDataDocument class. Chapter 12save - Oracle, SQLXML, .NET Data using Providers Actually, comes XmlDocument, and the XmlDocument class defines the Save Chapter 13XmlDataDocument - Developing a Custom Data from Provider method. As you know, you can use Save method to save your data in a string, stream, TextWriter, and XmlWriter.


Chapter 16 create - ASP.NET Server Controls and Data Binding First, you a DataSet object and fill it using a DataAdapter. The following example reads the Chapter 17 Building Real-World Web Applications Customers table from the Northwind Access database and fills data from the table to the DataSet: Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Dim sql As String = "SELECT * FROM Customers"

Chapter 20 As - COM Interoperability and Dim da SqlDataAdapter = ADO.NET New SqlDataAdapter(sql, conn) Chapter 21 Messaging ' Create and fill a DataSet Chapter 22 As - SQL Server and Notes on Performance Dim ds DataSet = ADO.NET: New DataSet() Appendix A - Relational Databases: Some Basic Concepts da.Fill(ds) Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Now, you create an instance of XmlDataDocument with the DataSet as an argument and call the Save Index method to save the data as an XML document: List of Figures List of Tables

Dim doc As XmlDataDocument = New XmlDataDocument(ds) List of Listings doc.Save("C:\\XmlDataDoc.xml") List of Sidebars Listing 6-24 shows a complete program. You create an XmlDataDocument object with a DataSet and call the Save method to save the DataSet data in an XML file. Listing 6-24: Saving the DataSet Data to an XML Document Imports System.Data Imports System.Data.SqlClient Imports System.Xml Module Module1

Sub Main() ADO.NET: Object Building Data-Driven Solutions ' Create Applied a Connection ISBN:1590590732 by Mahesh Chand and Talbot Dim ConnectionString As David String = "Integrated Security=SSPI;" & _ Apress © 2003 (928 pages) "Initial Catalog=Northwind;Data Source=MCB;" provides extensive of ADO.NET technology Dim conn This As text SqlConnection = coverage New SqlConnection() including ADO.NET internals, namespaces, classes, and conn.ConnectionString = ConnectionString interfaces, and takes a comprehensive look at XML ' Open the connection namespaces and classes, and how to integrate both with If conn.State ConnectionState.Open Then ADO.NET. conn.Open() End If Table of Contents Dim sql As String = "SELECT * FROM Customers" AppliedDim ADO.NET—Building Data-Driven Solutions da As SqlDataAdapter = New SqlDataAdapter(sql, conn) Introduction ' Create and fill a DataSet ChapterDim 1 -ds ADO.NET Basics As DataSet = New DataSet() Chapterda.Fill(ds) 2 - Data Components in Visual Studio .NET use SxlDataDocument's Save method to save data as an XML file Chapter'3 Now - ADO.NET in Disconnected Environments As XmlDataDocument = New XmlDataDocument(ds) ChapterDim 4 -doc ADO.NET in Connected Environments Chapterdoc.Save("C:\\XmlDataDoc.xml") 5 - Handling ADO.NET Events and dispose the connection Chapter'6 Close - Integrating XML with ADO.NET Windows ConnectionState.Open Then ChapterIf 7 conn.State - Data Binding and Forms Data-Bound Controls conn.Open() Chapter 8 - Constraints and Data Relations conn.Dispose() Chapter 9 - ADO.NET Exception Handling End If Chapter 10 - Working with the ODBC .NET Data Provider End Sub Chapter 11 - Stored Procedures and Views End Module Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

XmlDataDocument: Looking under the Hood


After looking at Listing 6-23, which illustrates the reading of an XML document in a DataGrid control, you must be wondering how it happened. The DataSet object handles everything for you under the hood:



doc.DataSet.ReadXml("C:\\outdata.xml")


Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Some Concepts As you see in this line,Databases: you're calling theBasic DataSet.ReadXml method to read an XML document. The Appendix B -extracts Commonly SQL Statements DataSet the Used document and defines tables and columns for you. Appendix C - ADO.NET Frequently Asked Questions

Generally, the root node of the XML document becomes a table; the document's name, namespace, Index

namespace URI, and prefix become the DataSet'sName,Namespace,NamespaceURI, and Prefix properties, respectively. If an element's children have one or more children, they become another table List of Tables inside the main table in a nested format. Anything left from the tables becomes columns of the table. The List of Listings value of a node becomes a row in a table. The DataSet takes care of all of this for you. List of Figures

List of Sidebars

ADO.NET: Building Data-Driven Solutions Navigating Applied in XML by Mahesh Chand and David Talbot

ISBN:1590590732

As you saw, XmlNode a pages) way to navigate DOM trees with the help of its FirstChild, Apressprovides © 2003 (928 ChildNodes,LastChild, PreviousNode, NextSibling, andtechnology PreviousSibling methods. This text provides extensive coverage of ADO.NET including ADO.NET internals, namespaces, classes, and

BesidesXmlNode, the XML and .NET has atwo more classes, which help you navigate XML documents. These interfaces, takes comprehensive look at XML classes are XPathDocument namespaces and andclasses, XPathNavigator. and how to integrate The System.Xml.XPath both with namespace defines ADO.NET. both of these classes. TheXPath namespace contains classes to provide read-only, fast access to documents. Before using

Table ofclasses, Contents these you must add a reference to the System.Xml.XPath namespace in your application. Applied ADO.NET—Building Data-Driven Solutions

XPathNodeIterator,XPathExpression, and XPathException are other classes defined in this Introduction namespace. The XPathNodeIterator class provides iteration capabilities to a node. Chapter 1 - ADO.NET Basics XPathExpression providesinselection criteria to select a set of nodes from a document based on those Chapter 2 - Data Components Visual Studio .NET criteria,3and the XPathException is an exception class. TheXPathDocument class provides a Chapter - ADO.NET in Disconnectedclass Environments fast cache XML document processing using XSLT and XPath. Chapter 4 -for ADO.NET in Connected Environments Chapter 5

- Handling ADO.NET Events You use the XPathDocument constructor to create an instance of XmlPathDocument. It has many

Chapter 6 - Integrating XML with ADO.NET overloaded constructors. You can pass an XmlReader,TextReader, or even direct XML filenames. Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Chapter 8


Using the XPathNavigator Class - ADO.NET Exception Handling

Chapter 9

Chapter 10 - Working withclass the ODBC .NET Data TheXPathNavigator implements theProvider functionality to navigate through a document. It has easy-toChapter 11 Stored Procedures and Views use and self-explanatory methods. You create an XPathNavigator instance by calling Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers XPathDocument's CreateNavigator method. Chapter 13 - Developing a Custom Data Provider

You can create a XPathNavigator object using by calling XmlDocument'sCreateNavigator method. Chapter 14also - Developing Database Web Applications ASP.NET For example, the following code CreateNavigator method to create a Chapter 15 - Using ADO.NET in Xmlcalls Web XmlDocument's Services XPathNavigator Chapter 16 - ASP.NET object: Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

' Load document Chapter 18 books.xml - Object-Relational Mapping in .NET Dim xmlDoc As XmlDocument = New XmlDocument() Chapter 19 - Mapped Objects: Performance Considerations and Data Binding xmlDoc.Load("c:\\books.xml") Chapter 20 - COM Interoperability and ADO.NET ' Create XPathNavigator object by calling CreateNavigator of XmlDocument Chapter 21 - Messaging Dim nav As XPathNavigator = xmlDoc.CreateNavigator()


Appendix - ADO.NET Asked Questions NoteC Don't forgetFrequently to add a reference to the System.Xml.XPath namespace to your project before Index using any of its classes. List of Figures

The class contains methods and properties to move to the first, next, child, parent, and List ofXPathNavigator Tables root of the document. List ofnodes Listings List of Sidebars

Using XPathNavigator Move Methods Table 6-7 describes XPathNavigator'sMove methods. Table 6-7: XPathNavigator Members

MEMBER

DESCRIPTION Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Moves to an attribute Apress © 2003 (928 pages)

MoveToAttribute

ISBN:1590590732

MoveToFirst This text provides Moves extensive to the coverage first sibling of ADO.NET of the current technology node including ADO.NET internals, namespaces, classes, and

MoveToFirstAttribute Moves to the first attribute interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with

MoveToFirstChild ADO.NET.

Moves to the first child of the current node

MoveToFirstNamespace

Moves the XPathNavigator to first namespace node of the current element

Table of Contents

Applied ADO.NET—Building Data-Driven Solutions MoveToId Moves to the node with specified ID Introduction

MoveToNamespace Chapter 1 - ADO.NET Basics

Moves to the specified namespace

Chapter 2 - Data Components in Visual Studio MoveToNext Moves to the.NET next node of the current node Chapter 3 - ADO.NET in Disconnected Environments

MoveToNextAttribute to the next attribute - ADO.NET in ConnectedMoves Environments

Chapter 4

Chapter 5 - Handling ADO.NET Events MoveToNextNamespace Moves to the next namespace Chapter 6 - Integrating XML with ADO.NET

MoveToParent

Chapter 7

Moves to the parent of the current node


Chapter 8 - Constraints and Data Relations MoveToPrevious Moves to the previous sibling of the current node Chapter 9 - ADO.NET Exception Handling

MoveToRoot

Moves to the root node


So, with the help of these methods, you can move through a document as a DOM tree. Listing 6-25 uses theMoveToRoot and MoveToFirstChild methods to move to the root node and first child of the root Chapter 13 - Developing a Custom Data Provider node. Once you have a root, you can display corresponding information such as the name, value, node Chapter 14 - Developing Database Web Applications using ASP.NET type, and so on. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


Chapter Listing16 6-25: - ASP.NET Moving Server to Root Controls and First and Data Child Binding Nodes Using XPathNavigator Chapter 17 - Building Real-World Web Applications Chapter 18 books.xml - Object-Relational Mapping in .NET ' Load document Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Dim xmlDoc As XmlDocument = New XmlDocument() ChapterxmlDoc.Load("c:\\books.xml") 20 - COM Interoperability and ADO.NET Chapter'21 - Messaging Create XPathNavigator object by calling CreateNavigator of XmlDocument ChapterDim 22 -nav SQL Server and ADO.NET: Notes Performance As XPathNavigator = on xmlDoc.CreateNavigator() Appendix A - Relational Databases: Some Basic Concepts

' BMove to root node Appendix - Commonly Used SQL Statements nav.MoveToRoot() Appendix C - ADO.NET Frequently Asked Questions Index Dim name As String = nav.Name

Console.WriteLine("Root node info: ") List of Figures Console.WriteLine("Base URI" + nav.BaseURI.ToString()) List of Tables Console.WriteLine("Name: " + nav.Name.ToString()) Console.WriteLine("Node Type: " + nav.NodeType.ToString()) List of Sidebars Console.WriteLine("Node Value: " + nav.Value.ToString()) List of Listings

If nav.HasChildren Then nav.MoveToFirstChild() End If

Now, using the MoveToNext and MoveToParent methods, you can move through the entire document. Listing 6-26 moves though an entire document and displays the data on the console. The GetNodeInfo method displays a node's information, and you call it recursively.

Listing 6-26: Reading a Document Using XPathNavigator


Imports Imports Imports Imports

ISBN:1590590732

System.Data Apress © 2003 (928 pages) System.Data.SqlClient This text provides extensive coverage of ADO.NET technology System.Xml including ADO.NET internals, namespaces, classes, and System.Xml.XPath interfaces, and takes a comprehensive look at XML

namespaces and classes, and how to integrate both with ADO.NET. Module Module1

Sub Main() ' Contents Load books.xml document Table of Dim xmlDoc As XmlDocument = New XmlDocument() Applied ADO.NET—Building Data-Driven Solutions xmlDoc.Load("c:\\books.xml") Introduction ' Create XPathNavigator object by calling CreateNavigator of XmlDocument Chapter 1 - ADO.NET Basics Dim nav As XPathNavigator = xmlDoc.CreateNavigator() Chapter 2


Chapter 3

- ADO.NET in Disconnected Environments ' Moce to root node

Chapternav.MoveToRoot() 4 - ADO.NET in Connected Environments ChapterDim 5 -name Handling AsADO.NET StringEvents = nav.Name ChapterConsole.WriteLine("Root 6 - Integrating XML with ADO.NET node info: ") ChapterConsole.WriteLine("Base 7 - Data Binding and Windows Forms Controls URI" Data-Bound + nav.BaseURI.ToString()) ChapterConsole.WriteLine("Name: 8 - Constraints and Data Relations " + nav.Name.ToString()) ChapterConsole.WriteLine("Node 9 - ADO.NET Exception HandlingType: " + nav.NodeType.ToString())

" + nav.Value.ToString()) ChapterConsole.WriteLine("Node 10 - Working with the ODBC .NETValue: Data Provider Chapter 11 - Stored Procedures and Views ChapterIf 12 nav.HasChildren - Oracle, SQLXML, and Then Other .NET Data Providers

nav.MoveToFirstChild() Chapter 13 - Developing a Custom Data Provider GetNodeInfo(nav) Chapter 14 - Developing Database Web Applications using ASP.NET End If End Sub Chapter 16 - ASP.NET Server Controls and Data Binding ' GetNodeInfo method Chapter 17 - Building Real-World Web Applications Public Sub GetNodeInfo(ByVal nav1 As XPathNavigator) Chapter 18 - Object-Relational Mapping in .NET Console.WriteLine("Name: " + nav1.Name.ToString()) Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Console.WriteLine("Node Type: " + nav1.NodeType.ToString()) ChapterConsole.WriteLine("Node 20 - COM Interoperability and ADO.NET Value: " + nav1.Value.ToString()) Chapter 15 - Using ADO.NET in Xml Web Services

Chapter 21 - Messaging Chapter'22 Server ADO.NET: Notes Performance If- SQL node hasand children, moveonto fist child. Appendix - Relational Databases: Some IfA nav1.HasChildren Then Basic Concepts Appendix B - Commonly Used SQL Statements nav1.MoveToFirstChild() Appendix C - ADO.NET Frequently Asked Questions Index

While nav1.MoveToNext()

GetNodeInfo(nav1) List of Figures List of Tablesnav1.MoveToParent()

End While List of Listings Else List of Sidebars nav1.MoveToNext() GetNodeInfo(nav1) End If End Sub End Module

Searching Using XPathNavigator

Select,SelectChildren,SelectAncestors, and SelectDescendents are other useful methods. ADO.NET: Building Data-Driven Solutions Specifically, theseApplied methods are useful when you need to select a document's items based on an XPath ISBN:1590590732 by Mahesh Chand and David expression. For example, you could use one Talbot when selecting nodes for the author tag only. Apress © 2003 (928 pages)

Now, say you want to text search and display all coverage tag nodes in the books.xml document. In This provides extensive of ADO.NET technology ADO.NET internals, namespaces, and Listing 6-27, you including use XPathNavigator's Select methodclasses, to apply a criteria (all elements with the and takes a comprehensive interfaces, tag) to read and display all the nodes.look at XML namespaces and classes, and how to integrate both with ADO.NET.

Listing 6-27: UsingXPathIterator and Select

Table of Contents ' Load books.xml document AppliedDim ADO.NET—Building Data-Driven Solutions xmlDoc As XmlDocument = New XmlDocument() Introduction xmlDoc.Load("c:\\books.xml") Chapter'1 Create - ADO.NET Basics XPathNavigator object by calling CreateNavigator of XmlDocument ChapterDim 2 -nav Data As Components XPathNavigator in Visual Studio = xmlDoc.CreateNavigator() .NET

for author's first name Chapter'3 Look - ADO.NET in Disconnected Environments First Name") ChapterConsole.WriteLine("Author 4 - ADO.NET in Connected Environments As XPathNodeIterator = _ ChapterDim 5 -itrator Handling ADO.NET Events Chapternav.Select("descendant::first-name") 6 - Integrating XML with ADO.NET

itrator.MoveNext() ChapterWhile 7 - Data Binding and Windows Forms Data-Bound Controls Console.WriteLine(itrator.Current.Value.ToString()) - Constraints and Data Relations End While

Chapter 8 Chapter 9



Applied ADO.NET: Building Data-Driven Solutions Working with Schemas by Mahesh Chand and David Talbot

ISBN:1590590732

XML schemas play a major role the .NET Framework, and Visual Studio .NET (VS .NET) provides many Apress © 2003 (928inpages) tools and utilities This to work with XML. The .NETcoverage Framework uses XML to transfer data from one application to text provides extensive of ADO.NET technology other. XML schemas define the structure and validation rules of XML including ADO.NET internals, namespaces, classes, anddocuments. You use XML Schema interfaces,to and takesXML a comprehensive Definition (XSD) language define schemas. look at XML namespaces and classes, and how to integrate both with VS .NET providesADO.NET. an XML designer to work with schemas. In this section, you'll learn how to take

advantage of the VS .NET XML designer and wizards to work with XML documents and databases. Table of Contents

Generating a New Schema


To generate a new schema, Chapter 1 - ADO.NET Basics create a new Windows application using File Ø New Ø Project Ø Visual Basic Projects Ø -Windows Application. Then just follow the steps outlined in the following sections. Data Components in Visual Studio .NET

Chapter 2 Chapter 3

- ADO.NET in Disconnected Environments Step 1: Adding an Empty Schema

Chapter 4


Chapter 5 add - Handling You can an XMLADO.NET schema Events to a project by right-clicking a project and then selecting Add Ø Add New Chapter 6 Integrating XML with opens ADO.NET Item. The Add New Item option the Add New Item dialog box, where you can select different Chapter 7 - To Data Binding andschema, Windowsyou Forms Data-Bound Controls templates. add an XML need to select the XML Schema template on this page. This page also allows you to specify the schema name. The default schema name is XMLSchema1.xsd. Next, click Chapter 8 - Constraints and Data Relations

the Open on the Add New Item page. Chapter 9 button - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

This action launches the XML designer, which allows you to design XML schemas. The default XML designer page like Figure 6-8. As you can see, there are two links available: Server Explorer and Toolbox.



Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings

Figure 6-8: The XML designer

List of Sidebars

As you might guess, the Server Explorer link launches the Server Explorer. (See Chapter 2 to learn more about the Server Explorer.) The Toolbox link launches a Toolbox that contains the XML Schema items rather than Windows or Web controls. If you click the XML option at the bottom of screen, you'll see that your XML looks like the following: Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Step 2: Adding Schema Items interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Once an empty schema is available in the XML designer, you can click the Toolbox link to open the Toolbox ADO.NET.

and add schema items (see Figure 6-9). Table of Contents


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Figure 6-9: The XML schema Toolbox

Appendix A - Relational Databases: Some Basic Concepts Appendix - Commonly Used Statements The XMLB designer works in SQL pretty much same way as the form designer. You drag components from the Appendix ADO.NET Frequently Questions ToolboxCto- the designer, and theAsked designer writes the code for you. As you can see in Figure 6-9, you can Index add an element, attribute, complexType, and other schema items to the form. List of Figures

First, let's add an element to the schema, dragging it from the Toolbox. Second, set its name and type in the designer. The default element looks like Figure 6-10. If you click the right-side column of the grid, you'll List of Listings see a drop-down list with element types. You can either select the type of an item from the list or define your List of Sidebars own type (which is a user-defined type). List of Tables


ISBN:1590590732


Table Figure of Contents 6-10: Adding a schema element and its type Applied ADO.NET—Building Data-Driven Solutions Introduction

For this example, define your own custom type. Define the first element as bookstore with a custom type - ADO.NET Basics ofbookstoretype.Figure 6-11 shows the bookstore element of bookstoretype.

Chapter 1 Chapter 2


Chapter 3


Chapter 4


Chapter 5 - 6-11: Handling ADO.NET Events Figure Adding a new bookstore element Chapter 6 - Integrating XML with ADO.NET Chapter 7 a- complexType Data Binding and Windows Formsa Data-Bound Controls Now add item by dragging complexType item to the XML designer (see Figure 6-12). Chapter 8 - Constraints and Data Relations Chapter 9



Figure A complexType itemin .NET Chapter 18 - 6-12: Object-Relational Mapping Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM item Interoperability ADO.NET A complexType can containand other types, too. You can add items to a complexType in many ways. You Chapter 21 -drag Messaging can either an item from the Toolbox to the complexType or right-click a complexType and use the Add Chapter option and 22 - its SQL suboptions Server and toADO.NET: add an item. Notes Figure on Performance 6-13 shows different items you can add to a complexType. Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 6-13: Adding other types to complexType item You can delete items by right-clicking and selecting Delete. You can also delete the entire complexType or other schema items by right-clicking the header of an item or right-clicking the left side of the item.

Now, rename the added complexType name to book and add four element types: title,author, AppliedNow ADO.NET: Building Data-Driven Solutions price, and category. your complexType book should now look like Figure 6-14. by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732


Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Figure 6-14: Thebook complexType and its elements Chapter 1 - ADO.NET Basics Chapter 2

- Data Components in Visual Studio .NET Next, add more complexType author with two elements: first-name and last-name. Your final Chapter 3 -one ADO.NET in Disconnected Environments

schema4 should now look like Figure 6-15. Chapter - ADO.NET in Connected Environments Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure Theauthor and book complexTypes in an XML schema Chapter 13 - 6-15: Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

You can now see the XML code for this schema by clicking the left-bottom XML button (see Figure 6-16).


Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 6-16: Viewing the XML code for a schema You just saw how the VS .NET Integrated Development Environment (IDE) provides a tool to design your custom schema.

Adding Schema from a Database Objects You can generate a typed DataSet (discussed in Chapter 4)—which actually is an XML schema—from a database table or other objects such as a view or a stored procedure. To test this option, you use the Server Explorer, which you can launch either by clicking the Server Explorer option of the XML designer or by

opening it from the View Ø Server Explorer menu item.


ISBN:1590590732 Mahesh from Chand David table, Talbot you simply open To create an XMLbyschema a and database the Server Explorer, expand a database © 2003 (928 pages) table, and drag aApress table onto the XML schema designer. For this example, drag the Employees table onto the designer. After dragging it, the extensive XML designer generates a schema for the table (see Figure 6-17). This text provides coverage of ADO.NET technology



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - 6-17: Mapped Objects: Performance Considerations and Data Binding Figure XML designer–generated schema Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

Listing 6-28 shows the generated XML code.

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Basic Concepts Listing 6-28: The XML Schema Some Generated for a Database Table Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Index

Applied ADO.NET: Building Data-DrivenminOccurs="0" Solutions ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) type="xs:dateTime" minOccurs="0" /> Notes col2onThen ChapterIf 22 i- SQL Performance NewTableStyle.GridColumnStyles.Add _ Appendix A - Relational Databases: Some Basic Concepts (existingTableStyle.GridColumnStyles(i)) Appendix B - Commonly Used SQL Statements End Appendix C -If ADO.NET Frequently Asked Questions Next Index ' Remove the existing table style and add new style List of Figures grid.TableStyles.Remove(existingTableStyle) List of Tables grid.TableStyles.Add(NewTableStyle) List of Listings End Sub Chapter 10 - Working with the ODBC .NET Data Provider

List of Sidebars

Reading information about a DataGrid's columns using a DataGridColumnStyle is simple. You just read the GridColumnStyleCollection using the GridColumnStyles property of DataGridTableStyle.Listing 7-30 reads a DataGrid's column styles and adds them to the ListBox control. Listing 7-30: Getting a DataGrid Columns' Style Using DataGridColumnStyle Private Sub GetInfoBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles GetInfoBtn.Click

Dim infoStr As String = "Visible Rows: " + _ Applied ADO.NET: Building Data-Driven Solutions DataGrid1.VisibleRowCount.ToString() ISBN:1590590732 by Mahesh Chand and David Talbot ListBox1.Items.Add(infoStr) Apress © 2003 (928 pages) infoStr = "Visible Cols: " + _ This text provides extensive coverage of ADO.NET technology DataGrid1.VisibleColumnCount.ToString() including ADO.NET internals, namespaces, classes, and ListBox1.Items.Add(infoStr) interfaces, and takes a comprehensive look at XML infoStr = "Total Rows: " + _and how to integrate both with namespaces and classes, ds.Tables(0).Rows.Count.ToString() ADO.NET. ListBox1.Items.Add(infoStr) infoStr = "Total Cols: " + _ Tableds.Tables(0).Columns.Count.ToString() of Contents Applied ADO.NET—Building Data-Driven Solutions ListBox1.Items.Add(infoStr) Introduction ' Get all table styles in the Grid and Column Styles Chapter 1 - ADO.NET Basics ' which returns table and column names Chapter Dim2 gridStyle - Data Components As DataGridTableStyle in Visual Studio .NET For3 Each gridStyle In DataGrid1.TableStyles Chapter - ADO.NET in Disconnected Environments = "Table Name: " + gridStyle.MappingName ChapterinfoStr 4 - ADO.NET in Connected Environments ChapterListBox1.Items.Add(infoStr) 5 - Handling ADO.NET Events As with DataGridColumnStyle ChapterDim 6 -colStyle Integrating XML ADO.NET colStyle In gridStyle.GridColumnStyles ChapterFor 7 -Each Data Binding and Windows Forms Data-Bound Controls infoStr = "Column: " + colStyle.MappingName Chapter 8 - Constraints and Data Relations ListBox1.Items.Add(infoStr) Chapter 9 - ADO.NET Exception Handling Next Chapter 10 - Working with the ODBC .NET Data Provider Next Chapter 11 - Stored Procedures and Views End Sub Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15the - Using ADO.NET Xml Web Now run application andinenter 1 in Services the Column 1 box and enter 2 in the Column 2 box and then click Chapter 16 - ASP.NET Server Controls andsee Data Binding the Exchange Columns buttons. You'll both columns switched their positions. Now if you click the Get Chapter Grid Columns 17 - Building and Tables Real-World Info button, Web Applications the output looks like Figure 7-10. Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 7-10: Getting a DataGrid control's column styles

Getting a Column Header Name Listing 7-31 returns the column name when a user right-clicks a DataGrid column header. Listing 7-31: Getting a DataGrid Column Header Name

Private Sub DataGrid1_MouseDown(ByVal sender As Object, _ ADO.NET: Building Data-Driven SolutionsHandles DataGrid1.MouseDown ByVal e As Applied System.Windows.Forms.MouseEventArgs) ISBN:1590590732 by Mahesh Chand and David Talbot Dim str As String = Nothing Apress © 2003 (928 pages) Dim pt As Point = New Point(e.X, e.Y) ThisDataGrid.HitTestInfo text provides extensive coverage of ADO.NET technology Dim hti As = DataGrid1.HitTest(pt) including ADO.NET internals, namespaces, classes, and ' If right mouse button clicked interfaces, and takes a comprehensive look at XML If e.Button = MouseButtons.Right namespaces and classes, and how toThen integrate both with If hti.Type = DataGrid.HitTestType.ColumnHeader Then ADO.NET. Dim gridStyle As DataGridTableStyle = _ DataGrid1.TableStyles("Customers") Table of Contents str = gridStyle.GridColumnStyles(hti.Column).MappingName.ToString() Applied ADO.NET—Building Data-Driven Solutions MessageBox.Show("Column Header " + str) Introduction End If ChapterEnd 1 -If ADO.NET Basics Chapter'2 If- Data left Components mouse button in Visualclicked Studio .NET MouseButtons.Left ChapterIf 3 e.Button - ADO.NET in=Disconnected EnvironmentsThen hti.Type = DataGrid.HitTestType.Cell Then Chapter 4 If- ADO.NET in Connected Environments = "Column: " + hti.Column.ToString() Chapter 5 -str Handling ADO.NET Events += ",XML Row: + hti.Row.ToString() Chapter 6 -str Integrating with " ADO.NET Chapter 7 -MessageBox.Show(str) Data Binding and Windows Forms Data-Bound Controls End If Chapter 8 - Constraints and Data Relations End If Chapter 9 - ADO.NET Exception Handling End Sub Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

Hiding a DataGrid's Columns

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 -learn UsingaADO.NET Xml Web Services Now you'll few moreinuses of a DataGrid control. Hiding a DataGrid column is simply a job of Chapter finding 16 the-right ASP.NET column Server andControls setting its and Width Data Binding property to 0. For an example, see the TotalDataGrid

sample17 that comes with the downloads from www.apress.com. Chapter - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

To make your program look better, you'll create a right-click pop-up menu, as shown in Figure 7-11.

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List ofFigure Tables 7-11: Pop-up menu on DataGrid right-click menu List of Listings List of Sidebars

To create a pop-up menu, you declare a ContextMenu and four MenuItem objects as sortAscMenu, sortDescMenu,findMenu, and hideMenu. You also define two more variables to store the current DataGridColumnStyle and column name as follows: Private curColName As String = Nothing Private curColumnStyle As DataGridColumnStyle

If DataGrid.HitTestType is ColumnHeader, you add menu items and get the current column, as shown in Listing 7-32. In this listing, you simply store the current DataGridColumnStyle and the name of the column.

Listing 7-32: Getting the Current DataGridColumnStyle


ISBN:1590590732

Case DataGrid.HitTestType.ColumnHeader Apress © 2003 (928 pages) ' Add context menus This text provides extensive coverage of ADO.NET technology popUpMenu = New internals, ContextMenu() including ADO.NET namespaces, classes, and popUpMenu.MenuItems.Add("Sort ASC") interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with popUpMenu.MenuItems.Add("Sort DESC") ADO.NET. popUpMenu.MenuItems.Add("Find") popUpMenu.MenuItems.Add("Hide Column") Me.ContextMenu = popUpMenu Table of Contents Me.BackColor = Color.Sienna Applied ADO.NET—Building Data-Driven Solutions sortAscMenu = Me.ContextMenu.MenuItems(0) Introduction sortDescMenu = Me.ContextMenu.MenuItems(1) Chapter 1 - ADO.NET Basics findMenu = Me.ContextMenu.MenuItems(2) Chapter 2 - Data Components in Visual Studio .NET hideMenu = Me.ContextMenu.MenuItems(3) Chapter 3 - ADO.NET in Disconnected Environments ' Find the Column header name Chapter 4 - ADO.NET in ConnectedAs Environments Dim gridStyle DataGridTableStyle = _ Chapter 5 - Handling ADO.NET Events dtGrid.TableStyles("Customers") Chapter 6 - Integrating XML with ADO.NET curColName = gridStyle.GridColumnStyles _ Chapter 7 - Data Binding and Windows Forms Data-Bound Controls (hti.Column).MappingName.ToString() Chapter 8 - Constraints and Data Relations curColumnStyle = gridStyle.GridColumnStyles(hti.Column) Chapter 9



Finally,12 you- Oracle, write the Find menu button.NET clickData event handler and set curColumnStyle.Width to 0: Chapter SQLXML, and Other Providers Chapter 13 - Developing a Custom Data Provider

Private hideMenuHandler(ByVal sender As System.Object, _ Chapter 14 -Sub Developing Database Web Applications using ASP.NET ByVal As System.EventArgs) Handles hideMenu.Click Chapter 15 e- Using ADO.NET in Xml Web Services 0 Data Binding ChaptercurColumnStyle.Width 16 - ASP.NET Server Controls=and End17Sub Chapter - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Implementing Custom Sorting in a DataGrid


By default a DataGrid provides you with sorting options when you click a DataGrid column. But there may be occasions when you don't want to use the default behavior and instead want to implement your Appendix A - Relational Databases: Some Basic Concepts own custom sorting. Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix B - Commonly Used SQL Statements

Appendix - ADO.NET Frequently Questions In FigureC7-11, you saw the Sort Asked ASC and Sort DESC menu options. As you probably remember from Index Chapter 3 and Chapter 4, sorting is easy to implement in a DataView. To sort a DataView, you simply List Figures setofthe Sort property of the DataView to the column name and to ASC or DESC for ascending and List of Tables descending sorting, respectively. Listing 7-33 shows the Sort ASC and Sort DESC menu event handler List code. of Listings List of Sidebars

Listing 7-33: Sorting a DataGrid Control's Columns Private Sub SortAscMenuHandler(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles sortAscMenu.Click Dim dv As DataView = ds.Tables("Customers").DefaultView dv.Sort = curColName + " ASC" dtGrid.DataSource = dv End Sub Private Sub SortDescMenuHandler(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles sortDescMenu.Click Dim dv As DataView = ds.Tables("Customers").DefaultView

dv.Sort = curColName + " DESC" Applied ADO.NET: dtGrid.DataSource = dv Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot End Sub Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Building a DataGrid Record Navigation System

Move methods are one of the features of the ADO recordset that don't appear in ADO.NET. A recordset providesMoveFirst,MoveNext,MovePrevious, and MoveLast methods to move to the first, next, Table of Contents previous and last record in a recordset (respectively). In this example, you'll implement move functionality Applied ADO.NET—Building Data-Driven Solutions in a DataGrid control. Introduction

Chapter - ADO.NET Basics Listing 17-34 implements move functionality in a custom recordset class called CustRecordSet.vb. (We Chapter - Data Components in Visual Studio .NET already2discussed how you can use BindingContext to move the current pointer from one position to Chapter 3 In - ADO.NET Disconnected Environments another.) this code,inCreateRecordSet simply fills and binds a DataSet to the grid. The Chapter FirstRecord, 4 - ADO.NET PrevRecord, in Connected NextRecord, Environments and LastRecord methods set the current position of the Chapter pointer5to the - Handling first row, ADO.NET currentEvents row -1, current row +1, and the last row (respectively). Chapter 6


Listing 7-34: CustRecordSet.vb - Data Binding and Windows Forms Data-Bound Controls

Chapter 7 Chapter 8


Imports Chapter 9 -System.Data.SqlClient ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

Public Chapter 11 Class - StoredCustRecordSet Procedures and Views Private dataAdapter AsOther SqlDataAdapter = Nothing Chapter 12 - Oracle, SQLXML, and .NET Data Providers Private dataSeta Custom As DataSet = Nothing Chapter 13 - Developing Data Provider Private dtGrid As DataGrid = Nothing Private frm As Form = Nothing Chapter 15 - Using ADO.NET in Xml Web Services Private mapName As String = Nothing Chapter 16 - ASP.NET Server Controls and Data Binding Public Sub CreateRecordSet(ByVal conn As SqlConnection, _ Chapter 17 - Building Real-World Web Applications ByVal sql As String, ByVal grid As DataGrid, ByVal curForm As Form, _ Chapter 18 - Object-Relational Mapping in .NET ByVal tableName As String) ChapterMe.dataAdapter 19 - Mapped Objects: Considerations and Data Binding = Performance New SqlDataAdapter(sql, conn) ChapterMe.dataSet 20 - COM Interoperability and ADO.NET = New DataSet("Customers") ChapterMe.dataAdapter.Fill(Me.dataSet, 21 - Messaging "Customers") ChapterdtGrid 22 - SQL=Server gridand ADO.NET: Notes on Performance Appendix A -=Relational Databases: Some Basic Concepts frm curForm Appendix mapName B - Commonly = tableName Used SQL Statements dtGrid.DataSource Me.dataSet Appendix C - ADO.NET Frequently=Asked Questions Index dtGrid.DataMember = "Customers" End Sub List of Figures Public List of Tables Sub FirstRecord() If frm.BindingContext(Me.dataSet, mapName) Is Nothing Then List of Listings Return List of Sidebars End If frm.BindingContext(Me.dataSet, mapName).Position = 0 End Sub Public Sub PrevRecord() If frm.BindingContext(Me.dataSet, mapName) Is Nothing Then Return End If frm.BindingContext(Me.dataSet, mapName).Position -= 1 End Sub Public Sub NextRecord() If frm.BindingContext(Me.dataSet, mapName) Is Nothing Then Return Chapter 14 - Developing Database Web Applications using ASP.NET

End If Applied ADO.NET: Building Data-Driven Solutions frm.BindingContext(Me.dataSet, mapName).Position += 1 by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

End Sub text provides extensive coverage of ADO.NET technology Public Sub This LastRecord() including ADO.NET internals, namespaces, classes,Is andNothing Then If frm.BindingContext(Me.dataSet, mapName) interfaces, and takes a comprehensive look at XML Return namespaces and classes, and how to integrate both with End If ADO.NET. frm.BindingContext(Me.dataSet, mapName).Position = _ frm.BindingContext(Me.dataSet, mapName).Count - 1 TableEnd of Contents Sub Applied ADO.NET—Building Data-Driven Solutions Introduction End Class Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3

- ADO.NET in Disconnected Environments Note this example, the tableEnvironments name is Customers.You may want to customize the name so it can Chapter 4 In - ADO.NET in Connected

for any database table. Chapter 5 work - Handling ADO.NET Events Chapter 6

- Integrating XML with ADO.NET Now create a Windows application and add a DataGrid control and four Button controls (Move First,

Chapter 7 - Data andand Windows Controls Move Next, MoveBinding Previous, Move Forms Last). Data-Bound The form's Load event calls FillDataSet, which creates a Chapter 8 - Constraints object and Data newCustRecordSet andRelations calls its CreateRecordSet method, which in turn fills data in a Chapter 9 - control ADO.NET Exception DataGrid and binds a Handling DataSet with the DataGrid control (see Listing 7-35). Chapter 10 - Working with the ODBC .NET Data Provider

Listing11 7-35: Creating a Custom Recordset Chapter - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 load - Developing a Custom Data Provider ' form Chapter 14 - Developing Database Web Applications using Private Sub Form1_Load(ByVal sender AsASP.NET System.Object, _ Chapter 15 -eUsing in Xml Web Services ByVal As ADO.NET System.EventArgs) Handles MyBase.Load ChapterFillDataGrid() 16 - ASP.NET Server Controls and Data Binding

End17Sub Chapter - Building Real-World Web Applications ' Fill DataGrid Chapter 18 - Object-Relational Mapping in .NET Private Sub FillDataGrid() Chapter 19 - Mapped Objects: Performance Considerations and Data Binding "SELECT * FROM Customers" Chaptersql 20 -=COM Interoperability and ADO.NET = New SqlConnection(connectionString) Chapterconn 21 - Messaging recordSet = New CustRecordSet() recordSet.CreateRecordSet(conn, sql, DataGrid1, Me, "Customers") Appendix A - Relational Databases: Some Basic Concepts End Sub Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix B - Commonly Used SQL Statements

Appendix C - ADO.NET Frequently Asked Questions Index List of on Figures Now the button click event handlers, simply call CustRecordSet'sFirstRecord,PrevRecord, List of Tables NextRecord, and LastRecord methods, as shown in Listing 7-36. List of Listings

Listing 7-36: Moving Record Button Click Event Handlers List of Sidebars ' Move First button click Private Sub MoveFirstBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles MoveFirstBtn.Click recordSet.FirstRecord() End Sub ' Move Previous button click Private Sub MovePrevBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles MovePrevBtn.Click recordSet.PrevRecord() End Sub

' Move next button click ADO.NET: Building Data-Driven Solutions Private SubApplied MoveNextBtn_Click(ByVal sender As System.Object, _ ISBN:1590590732 by Mahesh Chand and David Talbot ByVal e As System.EventArgs) Handles MoveNextBtn.Click Apress © 2003 (928 pages) recordSet.NextRecord() This text provides extensive coverage of ADO.NET technology End Sub ADO.NET ' Move lastincluding button clickinternals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Private Subnamespaces MoveLastBtn_Click(ByVal As System.Object, _ and classes, and how to sender integrate both with ByVal e As ADO.NET. System.EventArgs) Handles MoveLastBtn.Click recordSet.LastRecord() End Sub Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter The final 1 application - ADO.NET looks Basicslike Figure 7-12. Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - 7-12: ASP.NET Server Controls and Data Binding Figure DataGrid navigation system Chapter 17 - Building Real-World Web Applications

Tip18 You can implement the sameinfunctionality on a DataGrid control's right-click menu by adding Chapter - Object-Relational Mapping .NET four menu items thatPerformance allow users Considerations to move to theand first,Data next, previous, and last records of a Chapter 19 - Mapped Objects: Binding DataGrid. You can even your own DataGrid component with sorting, searching, and Chapter 20 - COM Interoperability anddevelop ADO.NET navigating features. Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Implementing Search in a DataGrid


You justCsaw how to implement sorting in a DataGrid control. After sorting, searching is one Appendix - ADO.NET Frequently custom Asked Questions more basic requirement of database-driven applications. There are two methods to implement search in a Index DataGrid List of Figurescontrol: List of Tables

Using the SELECT statement

List of Listings

List ofUsing Sidebars a DataSet and DataView

Searching Using the SELECT Statement You already used search functionality in a connected environment using the SQL SELECT statement. Do you remember using a SELECT statement with a WHERE clause? In a WHERE clause, you passed the criteria specifying the data for which you're looking. If you want to search in multiple tables, you construct a JOIN query with WHERE clause. You can even search for a keyword using the SELECT...LIKE statement, which was discussed in "The DataView in Connected Environments" section of Chapter 4. You use the SELECT statement in a DataAdapter, which reads data based on the SELECT statement and the criteria passed in it. However, using this method for searching may not be useful when you're searching data frequently—especially when you're searching data in a DataGrid. We suggest not using

this method when searching data in an isolated application and there's no other application updating the Applied ADO.NET: Building data. Why? The main reason is that every timeData-Driven you change Solutions the SELECT statement, you need to create a by Mahesh Chand and David Talbot newDataAdapter and fill the DataSet when you change theISBN:1590590732 SELECT statement. This method is useful Apress ©applications 2003 (928 pages) when there are multiple updating the data simultaneously and you want to search in the latest updated data. This text provides extensive coverage of ADO.NET technology

Searching

including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Using a DataTable and namespaces and classes, andDataView how to integrate both with ADO.NET.

TheDataTable and DataView objects provide members that can filter data based on criteria. (See "The DataView" section in Chapter 3 for more information.) You can simply create a DataView from a Table DataSet, of Contents set a DataView'sRowFilter property to the search criteria, and then bind the DataView to a DataGrid, which will display the filtered records. Applied ADO.NET—Building Data-Driven Solutions Introduction

Tip Using the same method, you can implement a Search or Find feature in a DataGrid control. You - ADO.NET Basics can also provide a Search option on a DataGrid control's header so that you know on which Chapter 2 - Data Components in Visual Studio .NET column a user has clicked. Chapter 3 - ADO.NET in Disconnected Environments Chapter 1

Chapter 4 application - ADO.NET looks in Connected Environments The new like Figure 7-13. Obviously, the Search button searches the column entered in Chapter 5 Handling ADO.NET Events the Column Name text box for a value entered in the Value text box. Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - 7-13: Relational Databases:search Some Basic Concepts Figure Implementing functionality in a DataGrid control Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Note If you search for a string, use a singe quote (') before and after the string.

Index

List Figuresthe Save method functionality in the following section. Weofdiscuss List of Tables

After creating a Windows application and adding controls to the form, define following variables: List of Listings List of Sidebars

' Developer defined variables Private conn As SqlConnection = Nothing Private connectionString As String = _ "Integrated Security=SSPI;Initial Catalog=Northwind;Data Source=MCB;" Private sql As String = Nothing Private searchView As DataView = Nothing Dim adapter As SqlDataAdapter = Nothing Dim ds As DataSet = Nothing

Now add the FillDataGrid method, which fills the DataGrid and creates a DataView called Applied Building Data-Driven Solutions searchView (see ListingADO.NET: 7-37). by Mahesh Chand and David Talbot

ISBN:1590590732

Apress © 2003 (928 pages) Listing 7-37: FillDataGrid Method This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and ' Fill DataGrid interfaces, and takes a comprehensive look at XML Private Subnamespaces FillDataGrid() and classes, and how to integrate both with ADO.NET. sql = "SELECT * FROM Orders"

conn = New SqlConnection(connectionString) adapter = New SqlDataAdapter(sql, conn) Table of Contents ds = New DataSet("Orders") Applied ADO.NET—Building Data-Driven Solutions adapter.Fill(ds, "Orders") Introduction DataGrid1.DataSource = ds.Tables("Orders") ChaptersearchView 1 - ADO.NET = Basics New DataView(ds.Tables("Orders")) ChapterDim 2 -cmdBuilder Data Components Visual Studio .NET As inSqlCommandBuilder = _ ChapterNew 3 -SqlCommandBuilder(adapter) ADO.NET in Disconnected Environments Chapter'4 Disconnect. - ADO.NET in Connected Environments Otherwise you would get Chapter'5 Access - Handling ADO.NET Events violations when try multiple operations Chapterconn.Close() 6 - Integrating XML with ADO.NET Chapterconn.Dispose() 7 - Data Binding and Windows Forms Data-Bound Controls End Chapter 8 Sub - Constraints and Data Relations Chapter 9



Now, the next step is to set a RowFilter of searchView based on the values entered in the Column Name and Value text fields. Listing 7-38 shows the code for the Search button. As you can see, the code Chapter 13 - Developing a Custom Data Provider sets the RowFilter of searchView and binds it to the DataGrid to display the filtered data. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter - Using ADO.NET in Click Xml Web Services Listing15 7-38: Seach Button Event Handler Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

Private Sub SearchBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles SearchBtn.Click ChapterIf 19 (TextBox1.Text.Equals(String.Empty)) - Mapped Objects: Performance Considerations and Data Binding Then Chapter 20 COM Interoperability and ADO.NET MessageBox.Show("Enter a column name") Chapter 21 - Messaging TextBox1.Focus() Chapter 22 - SQL Server and ADO.NET: Notes on Performance Return Appendix A Relational Databases: Some Basic Concepts End -If Appendix IfB (TextBox2.Text.Equals(String.Empty)) - Commonly Used SQL Statements Then MessageBox.Show("Enter a value") Appendix C - ADO.NET Frequently Asked Questions TextBox1.Focus() Index Return List of Figures End If List of Tables ' Construct a row filter and apply on the DataView List of Listings Dim str As String = TextBox1.Text + "=" + TextBox2.Text List of Sidebars searchView.RowFilter = str ' Set DataView as DataSource of DataGrid DataGrid1.DataSource = searchView End Sub Chapter 18 - Object-Relational Mapping in .NET

At this time, if you run the application, the data from the Orders table is filled in the DataGrid If you enter EmployeeID in the Column Name text box and 6 in the Value field and then click the Search button, the filtered data looks like Figure 7-14.


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Figure 7-14: Filtered data after searching

Chapter 7

- Data Binding and Windows Forms Data-Bound Controls Inserting, Updating, and Deleting Data through DataGrids Chapter 8 - Constraints and Data Relations Chapter - ADO.NET Exception Handlingcontrol is one of the most powerful, flexible, and versatile controls As you 9learned earlier, the DataGrid Chapter 10 in - Working the ODBC Data Provider available Windowswith Forms. It has.NET an almost unlimited number of properties and methods. You can add Chapter new records, 11 - Stored update Procedures records, and and Views delete existing records on a DataGrid with little effort, and you can Chapter easily save 12 - the Oracle, affected SQLXML, dataand in aOther database. .NET Data Providers Chapter 13 - Developing a Custom Data Provider

When a DataGrid control is in edit mode (the default mode), you can simply add a new record by clicking the last row of the grid and editing the column values. You can update data by changing the Chapter 15 - Using ADO.NET in Xml Web Services existing value of cells. You can delete a row by simply selecting a row and clicking the Delete button. Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 16 - ASP.NET Server Controls and Data Binding

Chapter 17 - Building Real-World WebaApplications In the previous example, you used Save Changes button on a form (see Figure 7-14). Now just write the Chapter - Object-Relational Mapping in .NET code in18 Listing 7-39 on the Save Changes button click to save the data. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Listing20 7-39: Saving Updated Data in a Data Source from a DataGrid Control Chapter - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 -Sub SQL Server and ADO.NET: Notes on Performance Private SaveBtn_Click(ByVal sender As System.Object, _ Appendix ByVal A -eRelational As System.EventArgs) Databases: Some Basic Handles Concepts SaveBtn.Click Appendix B - Commonly Used SQL Statements

Dim As DataSet = New DataSet() Appendix C -changeDS ADO.NET Frequently Asked Questions Index ' Data is modified

If (ds.HasChanges(DataRowState.Modified)) Then List of Figures changeDS = ds.GetChanges(DataRowState.Modified) List of Tables Dim changedRecords As Integer changedRecords = adapter.Update(changeDS, "Orders") List of Sidebars If (changedRecords > 0) Then MessageBox.Show(changedRecords.ToString() & _ " records modified.") End If End If ' Data is deleted If (ds.HasChanges(DataRowState.Deleted)) Then changeDS = ds.GetChanges(DataRowState.Deleted) Dim changedRecords As Integer changedRecords = adapter.Update(changeDS, "Orders") If (changedRecords > 0) Then MessageBox.Show(changedRecords.ToString() & _ List of Listings

" records deleted.") End If Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 End If by Mahesh Chand and David Talbot Apress © 2003 (928 pages) ' Data is added This text provides extensive coverage of ADO.NET If (ds.HasChanges(DataRowState.Added)) Then technology including ADO.NET internals, namespaces, classes, and changeDS = ds.GetChanges(DataRowState.Added) interfaces, and takes a comprehensive look at XML Dim changedRecords As Integer namespaces and classes, and how to integrate both with changedRecords ADO.NET. = adapter.Update(changeDS, "Orders") If (changedRecords > 0) Then MessageBox.Show(changedRecords.ToString() & _ Table of Contents " records added.") Applied ADO.NET—Building Data-Driven Solutions End If Introduction End If Chapter 1 ds.AcceptChanges() - ADO.NET Basics Chapter 2 DataGrid1.Refresh() - Data Components in Visual Studio .NET End3 Sub Chapter - ADO.NET in Disconnected Environments Chapter 4


Chapter 5


Chapter 6


As you can- Data see from Listing 7-39, you simply get the modified, deleted, and updated changes in a new Binding and Windows Forms Data-Bound Controls DataSet by calling the DataSet.GetChanges method and save the changes by calling the Chapter 8 - Constraints and Data Relations DataAdapter.Update method. In the end, you accept the changes by calling Chapter 9 - ADO.NET Exception Handling DataSet.AcceptChanges and refresh the DataGrid control by calling the DataGrid.Refresh Chapter 10 - Working with the ODBC .NET Data Provider method. Chapter 7



Summary


ISBN:1590590732

Data-bound controls are©definitely one of the greatest additions to GUI applications. In this chapter, we Apress 2003 (928 pages) discussed the basics of data binding and how data binding works technology in Windows Forms data-bound controls This text provides extensive coverage of ADO.NET and ADO.NET. We discussed some essential objects that participate including ADO.NET internals, namespaces, classes, and in the data-binding phenomena, interfaces, and takes a comprehensive look at XMLBindingManagerBase, including Binding, BindingContext, BindingsCollection, namespaces and classes, and how to integrate both with PropertyManager, CurrencyManager, and BindingContext. ADO.NET.

After discussing basics of data binding and how to use these objects, you learned about some data-bound controls and how to bind data using the data-binding mechanism. You also saw some practical usage of Table of Contents data binding and data-bound controls; specifically, you created a record navigation system with a Applied ADO.NET—Building Data-Driven Solutions DataGrid control. Some of the examples discussed in this chapter included changing DataGrid styles Introduction programmatically, binding data sources to various data-bound controls, building a record navigation Chapter 1 - ADO.NET Basics application, and implementing search, add, update, and delete record features in a DataGrid. Chapter 2


Chapter 3 chapter - ADO.NET in Disconnected Environments Thenext covers constraints and data relations in more detail. Chapter 4 - ADO.NET in Connected Environments Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 8: Constraints and DataISBN:1590590732 Relations by Mahesh Chand and David Talbot Apress © 2003 (928 pages) In chapter 3, you encountered constraints and data relations. In this chapter, we discuss constraints and This text provides coverage of with ADO.NET technology data relations in more detail. First, extensive we start this chapter a discussion of constraints and how ADO.NET including ADO.NET internals, namespaces, classes, and constraint objects maintain data integrity. Second, we discuss data relations. An object that encapsulates a interfaces, and takes a comprehensive look at XML data relationship namespaces may be a new many andconcept classes,for and how programmers. to integrate both with ADO.NET.

Understanding Constraints Table of Contents

Aconstraint is a rule used to automatically maintain the integrity of a column's data. When we say automatically, we mean that the database itself makes sure the rule is being followed when changes are Introduction made to the data. For example, a UNIQUE constraint on a column makes sure that there aren't any Chapter 1 values - ADO.NET Basics There are different types of constraints, including NOT NULL, UNIQUE, duplicate in a column. Chapter 2 -KEY, Data FOREIGN Components in Visual Studio .NET PRIMARY KEY, and CHECK constraints: Applied ADO.NET—Building Data-Driven Solutions

Chapter 3


Chapter 4


The NOT NULL constraint specifies that a column can't contain null values.

Chapter 5 UNIQUE - Handling ADO.NETenforces Events a rule of uniqueness on a column, which means two rows of the The constraint Chapter 6 - Integrating with ADO.NET column can't have XML duplicate values. A UNIQUE constraint may also apply to a combination of Chapter columns, 7 - Data which Binding means andthe Windows combination Forms Data-Bound of the columns Controls must be a unique value. For example, a

database table canand have twoRelations fields-a path and a file-and the combination of these fields must be Chapter 8 - Constraints Data unique maintain the unique file entry in the database. In this case, the path or file column may have Chapter 9 - to ADO.NET Exception Handling duplicate valueswith individually, they must be unique when used together. Chapter 10 - Working the ODBCbut .NET Data Provider Chapter 11 - Stored Procedures and Views

A PRIMARY KEY constraint on a column or combination of columns enforces both the UNIQUE constraint and the NOT NULL constraint. This type of constraint is enforced when you need to identify Chapter 13 - Developing a Custom Data Provider column values as unique items and not null values such as a customer ID number or an order Chapter 14 - Developing Database Web Applications using ASP.NET number. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


The constraint relationships between two tables. A foreign key in the first Chapter 16FOREIGN - ASP.NETKEY Server Controlsidentifies and Data the Binding table to aReal-World primary key in the second table. Foreign keys prevent actions that would ignore rows Chapter 17 points - Building Web Applications with key values when there Chapter 18foreign - Object-Relational Mapping in are .NETno primary keys with that value. For example, the Orders table of a havePerformance a foreign keyConsiderations on the CustomerID column of the Customers table, which Chapter 19database - Mappedmay Objects: and Data Binding would a user from entering an order that related to a nonexistent customer. Chapter 20 -prevent COM Interoperability and ADO.NET Chapter 21 - Messaging

The CHECK constraint enforces data integrity by limiting a column's values. For example, you can

Chapter 22 - SQL Servertype and as ADO.NET: Notes on Performance specify a column an integer, which means only integer values can be placed in a column. Appendix A - Relational Databases: Some Basic Concepts

To implement many ofUsed theseSQL constraints, ADO.NET provides various classes. In the following sections, we Appendix B - Commonly Statements discuss some of these classes, their Appendix C - ADO.NET Frequently Askedmembers, Questions and how to use them to implement constraints. Index

Implementing the Constraint Classes


The class represents a constraint and serves as a base class of the List ofConstraint Listings ForeignKeyConstraint and UniqueConstraint classes. This class provides three properties: List of Sidebars ConstraintName represents the name of a constraint, ExtendedProperties represents a collection of user-defined properties, and Table represents a DataTable object to which the constraint applies. Before you learn how to implement constraints on a table, you'll look at the constraint classes.

Implementing the ForeignKeyConstraint Class TheForeignKeyConstraint class creates a FOREIGN KEY constraint. In a primary key/foreign key relationship, first column acts as a parent column, and the second column acts as a child column. The ForeignKeyConstraint class has five overloaded constructors. Each of these constructors takes two DataColumn objects as a parent and a child column. Optionally, you can also specify the relation name. TheForeignKeyConstraint class provides properties that can represent the relation name; the

columns participating in the relationship; the accept, delete, and update rules; and so on. Table 8-1 Applied ADO.NET: Building Data-Driven describes the ForeignKeyConstraint class properties. Solutions ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) Table 8-1: The ForeignKeyConstraint Class Properties This text provides extensive coverage of ADO.NET technology PROPERTY including ADO.NET DESCRIPTION internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML AcceptRejectRule namespaces and Occurs classes, when and the how AcceptChanges to integrate both method with of a DataTable is ADO.NET. called. The parameter of AcceptRejectRule is represented by the

Table of Contents

AcceptRejectRule enumeration, which has two members: Cascade and None. The default action is None.

Applied ADO.NET—Building Data-Driven Columns ReturnsSolutions the child columns of a constraint. Introduction

ConstraintName

Chapter 1

- ADO.NET Basics

Represents the name of the constraint.

Chapter DeleteRule 2 - Data Components in Occurs Visual when Studioa.NET row is deleted. The parameter of DeleteRule is Chapter 3

represented by the Rule enumeration, which has four members: - ADO.NET in Disconnected Environments

Chapter 4

Cascade, None,SetDefault, and SetNull. The default action is - ADO.NET in Connected Environments

Chapter 5

- Handling ADO.NET Cascade. Events

Chapter 6 - Integrating XML with ADO.NET ExtendedProperties Chapter 7

Returns any user-defined properties that exist for the object.


RelatedColumns Represents Chapter 8 - Constraints and Data Relations the parent column of a constraint. Chapter 9 Table

- ADO.NET ExceptionReturns Handlingthe DataTable of a constraint.


UpdateRule Occurs when a row is updated. The parameter of UpdateRule is Chapter 11 - Stored Procedures and Views

represented by the Rule enumeration, which has four members: Cascade,None,SetDefault, and SetNull. The default action is Chapter 13 - Developing a Custom Data Provider Cascade. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


Chapter ASP.NETa Server Controls Data Binding Listing 16 8-1-creates FOREIGN KEYand constraint on the id column of custTable and the CustID column of Chapter 17 Building Real-World Web Applications ordersTable.custTable and ordersTable are two DataTable objects created by the Chapter 18 - Object-Relational and Mapping in .NET CreateCustomersTable CreateOrdersTable methods, respectively. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Listing20 8-1: Creating a FOREIGN Constraint Chapter - COM Interoperability andKEY ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server ADO.NET: = Notes on Performance Dim custTable As and DataTable CreateCustomersTable() Appendix Dim ordersTable A - Relational Databases: As DataTable Some Basic = CreateOrdersTable() Concepts

Dim parentColumn As DataColumn Appendix B - Commonly Used SQL Statements= custTable.Columns("id") Dim childColumn As DataColumn = ordersTable.Columns("CustID") Appendix C - ADO.NET Frequently Asked Questions Dim fkConst As ForeignKeyConstraint = New ForeignKeyConstraint _ Index "CustOrderConts", parentColumn, childColumn) List of Figures fkConst.DeleteRule = Rule.SetNull List of Tables fkConst.UpdateRule = Rule.Cascade fkConst.AcceptRejectRule = AcceptRejectRule.Cascade

List of Listings

List of Sidebars

Caution Be careful when using the Cascade action. The default action for AcceptRejectRule is None, but the default action for UpdateRule and DeleteRule is Cascade. Calling the Cascade action on DeleteRule deletes all the children rows, which are related using the FOREIGN KEY constraint.

Using the UniqueConstraint Class TheUniqueConstraint object represents a UNIQUE constraint, which ensures that the value of a column is unique. Table 8-2 describes the UniqueConstraint class properties.

Table 8-2: The UniqueConstraint Class Properties Applied ADO.NET: Building Data-Driven Solutions PROPERTY

by Mahesh Chand and David Talbot DESCRIPTION Apress © 2003 (928 pages)

ISBN:1590590732

This text provides extensive coverage of ADO.NET technology Returns an array of columns that this constraint affects including ADO.NET internals, namespaces, classes, and ConstraintName interfaces, and Represents takes a comprehensive the name oflook the constraint at XML namespaces and classes, and how to integrate both with ExtendedProperties Returns a collection of any user-defined properties that exist for the ADO.NET.

Columns

object IsPrimaryKey Table of Contents

Represents whether the constraint is a primary key

Applied ADO.NET—Building Data-Driven Table ReturnsSolutions the DataTable of a constraint Introduction Chapter ADO.NET Basics Listing 18-2-creates two UNIQUE constraints on the id column of custTable and the OrderId column of Chapter 2 - Data Components in Visual Studio .NET ordersTable. Chapter 3


Listing48-2: CreatinginaConnected UNIQUE Constraint Chapter - ADO.NET Environments Chapter 5


Chapter 6 - Integrating XML with ADO.NET ' Create unique constraints Chapter 7 - Data and Windows Forms Data-Bound Controls Dim idCol As Binding DataColumn = New DataColumn() Chapter Constraints and Data Relations idCol8 = -custTable.Columns("id") Chapter Dim unqConst1 9 - ADO.NET AsException UniqueConstraint Handling = _

New UniqueConstraint("idUnqConst1", idCol) Chapter 10 - Working with the ODBC .NET Data Provider idCol11= -ordersTable.Columns("OrderId") Chapter Stored Procedures and Views Dim unqConst2 As UniqueConstraint _ Chapter 12 - Oracle, SQLXML, and Other .NET Data=Providers New UniqueConstraint("idUnqConst2", idCol) Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Note You can also set the Unique property of a DataColumn to True to make a column unique. Chapter 3 discusses this technique.


Chapter - Mapped Objects: Performance Considerations and Data Binding Using19the ConstraintCollection Class Chapter 20 - COM Interoperability and ADO.NET

ADataTable can have multiple constraints. The ConstraintCollection class represents a Chapter 21 - Messaging collection constraints of aADO.NET: DataTable and accessed through the Constraints property of a Chapter 22 of - SQL Server and Notes on is Performance DataTable. This class provides Some two properties: List and Item. The List property returns a list of all Appendix A - Relational Databases: Basic Concepts the constraints in the collection an ArrayList object. The Item property is the indexer for the Appendix B - Commonly Used SQLinStatements ConstraintCollection class, which returns a constraint at a specified index. Appendix C - ADO.NET Frequently Asked Questions Index

Similar to other collection classes, the ConstraintCollection class also provides methods to add and

List of Figures remove items to the collection. Table 8-3 describes the ConstraintCollection class methods. List of Tables List of Listings Table 8-3: The ConstraintCollection Class Methods List of Sidebars

METHOD


Add

ISBN:1590590732 by Mahesh Chand and David Talbot This method adds a constraint to the collection. (The following Apress © 2003 (928 pages)

section describes in this method in more detail.)

AddRange CanRemove

This text provides extensive coverage of ADO.NET technology including ADO.NET namespaces, classes, andexisting collection. Addsinternals, a collection of constraints to the interfaces, and takes a comprehensive look at XML namespaces and classes, and how integratecan both Checks whether a to constraint bewith removed from the collection. ADO.NET.

Removes all constraints from a collection.

Clear

Indicates whether a constraint exists in the collection. Returns True if a constraint Applied ADO.NET—Building Data-Driven Solutionsexists; otherwise, returns False. This is useful when you need to remove or read a constraint from the collection. Introduction

Contains Table of Contents

Chapter 1 - ADO.NET Basics IndexOf Chapter 2

Returns the index of a constraint in the collection. You can use the

Chapter 3

- Data Components in constraint Visual Studio .NET name or an object. - ADO.NET in Disconnected Environments

Chapter 4


Chapter 5


OnCollectionChanged

An event raises when the constraint collection is changed by adding or removing constraints.

Remove Chapter 6 - Integrating XML withDeletes ADO.NET a constraint from the collection. You can specify the Chapter 7

constraint name or an object. - Data Binding and Windows Forms Data-Bound Controls

Chapter 8

- Constraints and Data Relations RemoveAt Removes a constraint at the specified index in the collection.

Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter - Stored Procedures and Views and their members. Next let's put these classes together and see You've 11 now seen the constraint classes Chapter how to 12 use- them Oracle, in SQLXML, applications. and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

Adding Removing Constraints Chapter 14 -and Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

You use the Add method of the ConstraintCollection to add new constraints to the collection of constraints associated with a DataTable.Listing 8-3 adds a FOREIGN KEY constraint to a collection and Chapter 17 - Building Real-World Web Applications removes the first constraint. As you can see from the code, the Contains method returns True if the Chapter 18 contains - Object-Relational Mapping in .NET collection a constraint, and the CanRemove method returns True if the program can delete the Chapter 19 -The Mapped Objects: Performance constraint. Remove method removesConsiderations the constraint.and YouData canBinding also use the RemoveAt method if you Chapter 20 COM Interoperability and ADO.NET want to delete a constraint based on the index. Chapter 16 - ASP.NET Server Controls and Data Binding


Listing22 8-3: Adding and Chapter - SQL Server andRemoving ADO.NET: Constraints Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL objects Statements ' Create two DataTable Appendix C - ADO.NET Frequently Asked Questions ' Customer and Orders Index Dim custTable As DataTable = CreateCustomersTable() List Dim of Figures ordersTable As DataTable = CreateOrdersTable()

Try List of Tables ' Add a foriegn key constraint List of Listings Dim parentColumn As DataColumn = custTable.Columns("id") List of Sidebars Dim childColumn As DataColumn = ordersTable.Columns("CustID") Dim fkConst As ForeignKeyConstraint = New ForeignKeyConstraint _ ("CustOrderConts", parentColumn, childColumn) fkConst.DeleteRule = Rule.SetNull fkConst.UpdateRule = Rule.Cascade fkConst.AcceptRejectRule = AcceptRejectRule.Cascade ordersTable.Constraints.Add(fkConst) Catch exp As Exception MessageBox.Show(exp.Message) End Try ' Create a DataSet and add DataTables to it

Dim ds As DataSet = New DataSet("CustOrderDataSet") Applied Building Data-Driven Solutions ' Add DataTables toADO.NET: a DataSet ISBN:1590590732 by Mahesh Chand and David Talbot ds.Tables.Add(custTable) Apress © 2003 (928 pages) ds.Tables.Add(ordersTable) This text provides extensive coverage of ADO.NET technology ' Enforce Constraints including ADO.NET internals, namespaces, classes, and ds.EnforceConstraints = True interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ' Using Contains, CanRemove and Remove methods ADO.NET.

' Get the first constraint Dim cnst1 As Constraint = ordersTable.Constraints(0) Table Try of Contents Applied ADO.NET—Building Data-Driven Solutions If ordersTable.Constraints.Contains(cnst1.ConstraintName) Then Introduction If ordersTable.Constraints.CanRemove(cnst1) Then Chapter 1 - ADO.NET Basics ordersTable.Constraints.Remove(cnst1) Chapter 2 -End Data If Components in Visual Studio .NET If Chapter 3 End - ADO.NET in Disconnected Environments Catch4 myException As Exception Chapter - ADO.NET in Connected Environments Chapter 5 Console.WriteLine(myException.Message) - Handling ADO.NET Events End Try Chapter 6 - Integrating XML with ADO.NET Chapter 7


Chapter 8


Chapter 9


Note You must set the DataSet property EnforceConstraints to True if you want to save the constraint in a DataSet.


Chapter 12 The - Oracle, SQLXML, and Other .NETand Data Providers Note CreateCustomersTable CreateOrdersTable methods return two DataTable Chapter 13 objects - Developing a Custom Data ProviderIf you're using constraints in a connected environment, you created programmatically. Chapter 14 can - Developing get theseDatabase DataTable Web Applications objects fromusing a DataSet ASP.NETusing DataSet.Tables("TableName") Chapter 15 or - Using DataSet.Tables(index). ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Listing 17 8-4-adds UNIQUE constraints to two tables. Chapter Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Listing 8-4: Adding UNIQUE Constraints


' Create unique constraints Dim idCol As DataColumn = New DataColumn() Chapter 22 - SQL Server and ADO.NET: Notes on Performance idCol = custTable.Columns("id") Appendix A - Relational Databases: Some Basic Concepts Dim unqConst1 As UniqueConstraint = _ Appendix B - Commonly Used SQL Statements New UniqueConstraint("idUnqConst1", idCol) Appendix C - ADO.NET Frequently Asked Questions idCol = ordersTable.Columns("OrderId") Index Dim unqConst2 As UniqueConstraint = _ List of Figures New UniqueConstraint("idUnqConst2", idCol) List of Tables ' Add constraints to DataTables List of Listings custTable.Constraints.Add(unqConst1) List of Sidebars ordersTable.Constraints.Add(unqConst2) Chapter 21 - Messaging

Reading All the Constraints Reading all the constraints is pretty simple. You just read all the items in the collection. Listing 8-5 reads all the constraints of a collection. Listing 8-5: Reading All the Constraints of a Collection Dim contCollection As ConstraintCollection = _

ordersTable.Constraints Applied ADO.NET: Building Data-Driven Solutions Dim str As String = "Number of Constraints:" & _ ISBN:1590590732 by Mahesh Chand and David Talbot contCollection.Count.ToString() © 2003 (928 pages) Dim i As Apress Integer This text provides extensive coverage of ADO.NET technology Dim cnst As Constraint including ADO.NET internals, namespaces, classes, and For Each cnst In contCollection interfaces, and takes a comprehensive look at XML str = str + ", " namespaces and classes, and how to integrate both with str = str + cnst.ConstraintName ADO.NET. Next Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Adding PRIMARY Chapter 1

KEY Constraints

- ADO.NET Basics

There's2no- specific primary key class to add a.NET PRIMARY KEY constraint to a DataTable. The Chapter Data Components in Visual Studio PrimaryKey property DataTable sets the primary key of that table, and you assign a DataColumn Chapter 3 - ADO.NET in of Disconnected Environments as the PrimaryKey property. Listing 8-6 creates a DataColumnCollection and sets it as the primary Chapter 4 - ADO.NET in Connected Environments key of the Chapter 5 -CustTable. Handling ADO.NET Events Chapter 6


Chapter 7


Listing 8-6: Adding a PRIMARY KEY Constaint to a DataTable

Chapter 8

- Constraints and Data Relations Dim custTable AsException DataTable = CreateCustomersTable() Chapter 9 - ADO.NET Handling

' Make the ID column the primary key column. Dim PrimaryKeyColumns() As DataColumn = New DataColumn(1) {} Chapter 11 - Stored Procedures and Views PrimaryKeyColumns(0) = custTable.Columns("id") Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers custTable.PrimaryKey = PrimaryKeyColumns Chapter 10 - Working with the ODBC .NET Data Provider



Using SQL Statements to Add and Remove Constraints


Chapter 18 - Object-Relational in .NETusing SQL may be a better way to add constraints to a When working in a connectedMapping environment, Chapter database 19 table. - Mapped YouObjects: can addPerformance constraints to Considerations a table whenand youData create Binding a table or by altering an already

existing20 table. Chapter - COM Interoperability and ADO.NET Chapter 21 - Messaging

TheCREATE TABLE SQL statement allows you to set a column as a constraint when you create a table. TheCONSTRAINT keyword sets a column as the specified constraint. For example, the following SQL Appendix A - Relational Databases: Some Basic Concepts statement creates a table with myId as the primary key: Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix B - Commonly Used SQL Statements


Dim sql As String = "CREATE TABLE myTable" & _ "(myId INTEGER CONSTRAINT PKeyMyId PRIMARY KEY," & _ List of Figures "myName CHAR(50), myAddress CHAR(255), myBalance FLOAT)" Index

List of Tables

List of Listings List of can Sidebars You always add and delete constraints from a database table using the ALTER TABLE SQL

statement. If you read the SQL documentation, you'll see that this statement allows options such as ADD CONSTRAINT and DROP CONSTRAINT to add and remove constraints. If you're working in a connected environment and you can execute commands (through SqlCommand), using SQL statements to add and remove constraints is preferable because it entails less overhead and code and has better performance.

AppliedData ADO.NET: Building Data-Driven Solutions Understanding Relations by Mahesh Chand and David Talbot

ISBN:1590590732

Until now it was the job of the (928 database Apress © 2003 pages) server to maintain data relationships, but with the flexibility of ADO.NET, now programmers can also create and maintain data relationships in a disconnected This text provides extensive coverage of ADO.NET technology environment. A data relationship relates two tables to each other through their columns-for example, a including ADO.NET internals, namespaces, classes, and interfaces, and a comprehensive lookrecords at XML of a customer, and the Orders table customer/order relationship. Thetakes Customers table stores and and how integrate has bothonly withone record in the Customers table, stores records of namespaces orders made byclasses, customers. Eachtocustomer ADO.NET. which is identified by a unique column value called Customer Id. Each order is related to a customer, which has a column that stores the customer ID. The Orders table can have multiple records for a single customer. In this scenario, the Customer Id row in the Customers table acts as a parent row, and all Table of Contents related rows in the OrdersData-Driven table act as its child rows. One condition in this example is that the data type of Applied ADO.NET—Building Solutions both the parent and row columns must be identical. Introduction Chapter 1

- ADO.NET Basics In ADO.NET, the DataRelation class represents a data relation between two DataTable objects, and Chapter 2 - Data Components in Visual Studio .NET theDataRelationCollection represents a collection of data relations. Chapter 3

- ADO.NET in Disconnected Environments In a connected environment, you can access and maintain data relations through a DataSet. The Chapter 4 - ADO.NET in Connected Environments

Relations propertyADO.NET of the DataSet Chapter 5 - Handling Events returns a collection of data relations associated with that DataSet in the form a DataRelationCollection object. The ChildRelations and ParentRelations Chapter 6 - of Integrating XML with ADO.NET properties a DataTable theForms child relations andControls parent relations associated with that Chapter 7 -ofData Binding and return Windows Data-Bound DataTable. Chapter 8 - Constraints and Data Relations Chapter 9

- ADO.NET Exception Handling As you know from "The DataRow" section of Chapter 3, the DataRow also provides methods to return a

Chapter 10 - Working with the The ODBCGetParentRow .NET Data Provider row's parent and child rows. method of a DataRow returns the parent row of a Chapter 11 Stored Procedures and Views DataRow, and the GetParentRows method returns all parent rows related to a DataRow. The Chapter 12 - Oracle, SQLXML, and Other Data Providers GetChildRows method returns all the.NET child rows associated with a DataRow. Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Appliedthe ADO.NET: Building Data-Driven Solutions Understanding DataRelation and DataRelationCollection Objects by Mahesh Chand and David Talbot

ISBN:1590590732

TheDataRelation class represents Apress © 2003 (928 pages)a parent/child relationship between two tables. The DataRelation's overloaded constructors you of to ADO.NET create a DataRelation object from a parent This text provides extensive allow coverage technology and a child column or a collection of columns. The first argument of the constructors is the name of the including ADO.NET internals, namespaces, classes, and interfaces, andarguments takes a comprehensive look at XML relation. The second and third are the parent and child column(s), respectively. The last namespaces andtype, classes, and how to integrate with to create a constraint. optional argument is a Boolean which indicates whether both you want ADO.NET.

Before you create a DataRelation, let's fill a DataSet from two tables. Listing 8-7 fills a DataSet from the Customers and Orders tables. Table of Contents Applied Data-Driven ListingADO.NET—Building 8-7: Filling a DataSet fromSolutions Two Tables Introduction Chapter 1

- ADO.NET Basics

' Create a Connection Object Chapter 2 - Data Components in Visual Studio .NET Dim conn As SqlConnection = New SqlConnection(ConnectionString) Chapter 3 - ADO.NET in Disconnected Environments SQL = "SELECT * FROM Customers" Chapter 4 - ADO.NET in Connected Environments conn.Open() Chapter 5 - Handling ADO.NET Events Dim adapter As SqlDataAdapter = New SqlDataAdapter(SQL, conn) Chapter 6 -As Integrating XML=with Dim ds1 DataSet NewADO.NET DataSet("Customers") Chapter 7 Data Binding and Windows Forms Data-Bound Controls adapter.Fill(ds1, "Customers") Chapter - Constraints and Data Relations SQL =8 "SELECT * FROM Orders" Chapter 9 -=ADO.NET Exception Handling adapter New SqlDataAdapter(SQL, conn) Chapter 10 -As Working with the .NET Data Provider Dim ds2 DataSet = ODBC New DataSet("Orders") Chapter adapter.Fill(ds2, 11 - Stored Procedures "Orders") and Views ds1.Merge(ds2) Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Now let's create a DataRelation between the CustomerId column of the Customers table and the CustomerID column of Orders table (see Listing 8-8).

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter - Object-Relational Mapping in .NET Listing18 8-8: Creating a DataRelation


' Get the DataColumn objects from Customers ' and Orders tables of a DataSet Chapter 22 - SQL Server and ADO.NET: Notes on Performance Dim parentCol As DataColumn = New DataColumn() Appendix A - Relational Databases: Some Basic Concepts Dim childCol As DataColumn = New DataColumn() Appendix B - Commonly SQL aStatements 'Retrieve columnsUsed from DataSet Appendix C ADO.NET Frequently Asked Questions parentCol = ds1.Tables("Customers").Columns("CustomerID") Index childCol = ds1.Tables("Orders").Columns("CustomerID") List of Figures Dim bConstraints As Boolean List of Tables bConstraints = True List ' of Create Listings a DataRelation. Dim CustOrderRelation As DataRelation = _ List of Sidebars New DataRelation("CustOrdersRelation", parentCol, childCol, bConstraints) Chapter 21 - Messaging

Now you can add a DataRelation to a DataSet using the Add method of DataRelationCollection, which you access through the DataSet.Relations property. (We dicuss DataRelationCollection in a moment.) Use this code to add the DataRelation: ' Add the relation to the DataSet. ds1.Relations.Add(CustOrderRelation)

Even multiple sets of columns can participate in a relationship. The following code uses two columns to Applied ADO.NET: Building Data-Driven Solutions participate in a data relation: by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

Dim parentCols() As DataColumn This text provides extensive coverage of ADO.NET technology Dim childCols() As ADO.NET DataColumn including internals, namespaces, classes, and parentCols(0)interfaces, = DataSet1.Tables("Customers").Columns("CustID") and takes a comprehensive look at XML and classes, and how to integrate both with parentCols(1)namespaces = DataSet1.Tables("Customers").Columns("OrdID") ADO.NET. childCols(0) = DataSet1.Tables("Orders").Columns("CustID") childCols(1) = DataSet1.Tables("Orders").Columns("OrdID") Dim CustOrderRel As DataRelation Table of Contents CustOrderRel = New DataRelation("CustomersOrders", parentCols, childCols) Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1 - ADO.NET Basics After creating a DataRelation object, the next step is to see what properties are available in the Chapter 2 - Data Components Visual Studio the .NET DataRelation class. Tablein8-4 describes DataRelation class properties. Chapter 3


Chapter 4 - The ADO.NET in ConnectedClass Environments Table 8-4: DataRelation Properties Chapter 5


Chapter 6


PROPERTY

DESCRIPTION

Chapter 7 - Data Binding and Windows Forms Data-Bound ChildColumns Returns all child columnsControls of a relation Chapter 8


Chapter 9


ChildKeyConstraint

Returns the FOREIGN KEY constraint of a relation if any available

Chapter 10 - Working with the ODBC .NET Data Provider ChildTable Returns the child table (DataTable) Chapter 11 - Stored Procedures and Views

DataSet

Returns the DataSet to which a relation belongs


Chapter ExtendedProperties 13 - Developing a CustomReturns Data Provider the collection of custom properties Chapter 14 - Developing Database Web Applications using ASP.NET

Nested

Represents whether a DataRelation is nested (both get and set)


ParentColumns Chapter 16 - ASP.NET Server Controls Returns and all Data parent Binding columns of a relation Chapter 17 - Building Real-World Web Applications

ParentKeyConstraint

Returns the UNIQUE constraint of the parent column


ParentTable Returns the parent tableand (DataTable) of a relation Chapter 19 - Mapped Objects: Performance Considerations Data Binding Chapter 20 - COM Interoperability and ADO.NET

RelationName


Represents the name of the relation (both get and set)

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix - Relational Databases: Basic Concepts You canAalso create nested data Some relations. For example, if in addition to the Customers and Orders tables Appendix you haveB an - Commonly Items table Used thatSQL stores Statements data related to items such as Item ID, location, and so on, then you

can create more Frequently relation between the Orders and Items tables using the same steps you took for the Appendix C - one ADO.NET Asked Questions Customers and Orders tables. Index List of Figures

Now you'll learn how to access a DataRelation's properties. Listing 8-9 reads the DataSet, ParentTable,ChildTable,ParentColumns,ChildColumns, and RelationName properties of List of Listings DataRelation. List of Tables

List of Sidebars

Listing 8-9: GettingDataRelation Properties ' Getting a DataRelation properties Dim dtSet As DataSet = dtRelation.DataSet ' Getting Tables Dim pTable As DataTable = dtRelation.ParentTable Dim chTable As DataTable = dtRelation.ChildTable ListBox1.Items.Add("Parent Table: " + pTable.TableName) ListBox1.Items.Add("Child Table: " + chTable.TableName) 'Getting columns Dim parentCols() As DataColumn

Dim childCols() As DataColumn Applied ADO.NET: Building Data-Driven Solutions parentCols = dtRelation.ParentColumns ISBN:1590590732 by Mahesh Chand and David Talbot childCols = dtRelation.ChildColumns Apress © 2003 (928 pages) ' Print the ColumnName of each column. text provides extensive coverage of ADO.NET technology Dim i As This Integer including ADO.NET internals, namespaces, classes, and ListBox1.Items.Add("Parent Columns:") interfaces, and takes a comprehensive look at XML For i = 0namespaces To parentCols.GetUpperBound(0) and classes, and how to integrate both with ListBox1.Items.Add(parentCols(i).ColumnName) ADO.NET. Next i ListBox1.Items.Add("Child Columns:") Table ofFor Contents i = 0 To childCols.GetUpperBound(0) Applied ADO.NET—Building Data-Driven Solutions ListBox1.Items.Add(childCols(i).ColumnName) Introduction Next i Chapter'1 Data - ADO.NET Basics name relation Chapter ListBox1.Items.Add("DataRelation 2 - Data Components in Visual Studio .NET Name:" + dtRelation.RelationName) Chapter 3


Chapter 4


Chapter 5


You just saw how to create a DataRelation object, add it to a DataSet, and access its properties. Now - Integrating XML with ADO.NET let's look at the DataRelationCollection class, which is a gateway to access data relations.

Chapter 6 Chapter 7


Chapter 8 - Constraints and Data Relations TheDataRelationCollection class represents a collection of DataRelation objects of a Chapter 9 -which ADO.NET Exceptionthrough Handling DataSet, is accessed the Relations property of the DataSet. The Count property of Chapter 10 - Working with the ODBC .NETthe Data Provider DataRelationCollection returns number of data relations in a collection, and the Items Chapter 11allows - Stored Views property youProcedures to access and a DataRelation based on the index in the collection. Like the other Chapter collection 12 classes, - Oracle, this SQLXML, classand alsoOther provides .NETAdd, DataRemove, Providersand other methods. Table 8-5 describes these Chapter methods. 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Table 8-5: DataRelationCollection Chapter 15 - The Using ADO.NET in Xml Web Services Class Methods Chapter 16 - ASP.NET Server Controls and Data Binding

METHOD

DESCRIPTION


Add 18 - Object-Relational Adds a DataRelation to the collection. Chapter Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

AddRange

Copies an array of DataRelation objects to the end of this collection.


CanRemove ReturnsTrue if the specified DataRelation can be removed from the Chapter 21 - Messaging collection; otherwiseNotes False. Chapter 22 - SQL Server and ADO.NET: on Performance Appendix ClearA - Relational Databases: Some Basic Concepts

Removes all DataRelation objects from the collection.


Contains Returns True ifAsked a collection contains the specified DataRelation. You should Appendix C - ADO.NET Frequently Questions Index List of Figures ListIndexOf of Tables List of Listings

make sure that a DataRelation exists in the collection before calling the Remove method to avoid exceptions. Returns the index of the specified data relation.

Remove

Deletes the specified data relation from the collection.

RemoveAt

Removes the data relation at the specified index.

List of Sidebars

Listing 8-10 calls the Contains,CanRemove, and Remove methods to delete a data relation from the collection. Listing 8-10: Deleting a Data Relation from the Collection Dim dtRelCollection As DataRelationCollection = dtSet.Relations If (dtRelCollection.Contains("CustOrdersRelation")) Then If (dtRelCollection.CanRemove(dtRelation)) Then dtRelCollection.Remove(dtRelation)

End If Applied ADO.NET: Building Data-Driven Solutions End If by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Summary


ISBN:1590590732

Managing data relations Apress ©and 2003constraints (928 pages) programmatically is a new concept for developers. In this chapter, you learned how This ADO.NET helps createcoverage and manage data relations and constraints. text provides you extensive of ADO.NET technology including ADO.NET internals, namespaces, classes, and

Exception and error handling is another important part look of programming. In next chapter, you'll learn how to interfaces, and takes a comprehensive at XML namespaces and classes, andof how to integrate both with handle exceptions in your code with the help ADO.NET classes. ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 9: ADO.NET Exception ISBN:1590590732 Handling by Mahesh Chand and David Talbot

Overview


This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Effective exception interfaces, and error and handling takes ais comprehensive one of the most look important at XML things to learn in order to write reliable namespaces In and classes, andwe how to integrate and error-proof applications. this chapter, discuss how toboth usewith the exception and error handling ADO.NET.

classes provided by the .NET Framework.

If you come from a C++ background, you're probably familiar with different exception handling methods such as C++ exception handling, structured exception handling, and MFC exceptions. If you come from a Applied ADO.NET—Building Data-Driven Solutions Visual Basic (VB) background, you're probably familiar with the On Error statement. Although you can Introduction continue to use these techniques to handle errors, .NET implements exceptions differently. In addition, all Chapter 1 - ADO.NET Basics (C# and VB .NET) share the same mechanism. Now VB developers can enjoy .NET-supported languages Chapter 2 rich - Data Components in Visual .NET the same exception handling that Studio C++ developers enjoy.

Table of Contents

Chapter 3

- ADO.NET in Disconnected Environments Note .NET exception handling is beyond the scope of this book. In this chapter, we Chapter 4 Discussing - ADO.NET in Connected Environments

on ADO.NET Chapter 5 concentrate - Handling ADO.NET Eventsexception handling classes only. Chapter 6


VB .NET supports two types of exceptions-unstructured and structured. Remember using the On Error and Windows Forms Data-Bound Controls statement -inData VB?Binding Using the On Error statement is unstructured handling. In other words, you place the Chapter 8 - statement Constraintsat and Relations On Error theData beginning of a block of code and errors are handled at the end of the block. Chapter 9 ADO.NET Exception Handling Unstructured exception handling also employs the Error and Resume statements. All the code after the Chapter 10 - statement Working with the ODBC .NET Data Provider On Error is within the scope of the error handler. If there's another On Error statement, then Chapter 11 Stored Procedures and Views that becomes the active error handler. However, structured exception handling is a better approach, and Chapter Oracle,why SQLXML, and Other .NET the DataOn Providers there's 12 no -reason you should be using Error statement. Chapter 7


Structured handling works little differently unstructured handling. If you come from a C++ Chapter 14 -exception Developing Database Web a Applications usingthan ASP.NET background, you're probably familiar with Try...Catch blocks. However, if you haven't encountered them before, it's OK-they're simple enough. Specifically, you place the code within a Try block that you Chapter 16 - ASP.NET Server Controls and Data Binding think may cause an exception, and when an exception rises, the control goes to the Catch block. Chapter 15 - Using ADO.NET in Xml Web Services



Applied ADO.NET: Building Data-Driven Solutions Why Use Exception Handling? by Mahesh Chand and David Talbot

ISBN:1590590732

If you've been writing software for pages) a while, you're probably familiar with why you want to handle exceptions. Apress © 2003 (928 Whenever an exception occurs in a program,coverage if there'sofno exception handling, the program crashes with This text provides extensive ADO.NET technology system-generated messages. Unfortunately, system-generated messages are often incomprehensible. including ADO.NET internals, namespaces, classes, and and takes comprehensive lookand at XML Instead of systeminterfaces, messages, you canahandle exceptions generate user-readable messages. Let's namespaces howc:\abc.txt. to integrate both with take a simple example. Listingand 9-1classes, opens and the file ADO.NET.

Listing 9-1: Opening a File Table of Contents Applied Imports ADO.NET—Building System.IO Data-Driven Solutions

Module Module1 Introduction Sub1 Main() Chapter - ADO.NET Basics FileMode.Open) Chapter 2 File.Open("c:\\abc.txt", - Data Components in Visual Studio .NET End3 Sub Chapter - ADO.NET in Disconnected Environments End Module Chapter 4 - ADO.NET in Connected Environments Chapter 5


Chapter 6


Chapter 7

Data Binding and Windows Forms Data-Bound Controls What if the- file c:\abc.txt doesn't exist? Well, you get a lengthy error message, which looks like Figure Chapter 8 - Constraints and Data Relations 9-1. Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - 9-1: Object-Relational Mapping in .NET Figure A system-generated error Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Now let's modify this program little bit to make the error message more readable. As you can see from this Listing 9-2, you handle the exception using a simple Try...Catch block.


Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Basic Concepts Listing 9-2: A SimpleDatabases: ExceptionSome Handling Block Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Imports System.IO Module Module1 List of Figures Sub Main() List of Tables Try List of Listings File.Open("c:\\abc.txt", FileMode.Open) List of Sidebars Catch exp As Exception Console.WriteLine("Exception Ocurred :" + exp.Message.ToString()) End Try End Sub End Module Index

If you run the program, the output now looks like Figure 9-2, which not only handles the exception but also reports the cause of exception.


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a error comprehensive Figure 9-2: An exception-handled message look at XML namespaces and classes, and how to integrate both with ADO.NET.

Using Try...Catch Statements Table of Contents

Using ADO.NET—Building a Try...Catch statement is pretty straightforward. First, you decide what code you want the error Applied Data-Driven Solutions handler to monitor. Second, you place that code inside the Try...Catch block. When an exception Introduction occurs 1within that block of the code, the control goes to the Catch block and handles the exception the Chapter - ADO.NET Basics way you've Listing 9-3 showsStudio a simple Chapter 2 - specified. Data Components in Visual .NETTry...Catch block. Chapter 3


Chapter 4


Chapter 5


Try 6 Chapter


Listing 9-3: A Simple Try...Catch Block

' Place your code that may generate - Data Binding and Windows Forms Data-Bound Controls ' an exception in this block. Chapter 8 - Constraints and Data Relations Catch [optional filters] Chapter 9 - ADO.NET Exception Handling ' This code executes when the Try block fails and Chapter 10 - Working with the ODBC .NET Data Provider ' the filter on the Catch statement is true. Chapter 11 - Stored Procedures and Views End Try Chapter 7

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 159-3, - Using ADO.NETfilter in Xml Web Services In Listing the optional describes the type of error you want to handle. For example, if you want to Chapter handle16 memory-related - ASP.NET Server exceptions, Controls and you Data placeBinding a memory-related filter within the block. You'll learn about

filters in17the "Defining Custom Filters and Error Messages" section. Chapter - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Using Try...Catch...Finally Statements


TheTry...Catch...Finally construct is an extended version of the Try...Catchstatement. If an Chapter 21 - Messaging error occurs during the and execution of any code the Try section, then control moves to the Catch Chapter 22 - SQL Server ADO.NET: Notes on inside Performance block when the filter condition is True. The Finally Appendix A - Relational Databases: Some Basic Concepts block always executes last, just before the error handlingBblock loses scope, regardless of whether an exception occurred. The Finally block is the Appendix - Commonly Used SQL Statements perfect place to cleanFrequently up by closing files and disposing objects. Listing 9-4 shows a simple Appendix C - ADO.NET Asked Questions Try...Catch...Finally statement.

Index

List of Figures Listing 9-4: The Try...Catch...Finally Statement List of Tables List of Listings

Try ' Place your code that may generate ' an exception in this block. Catch [optional filters] ' This code executes when the Try block fails and ' the filter on the Catch statement is true. Finally 'Release and dispose objects here. End Try

List of Sidebars

Nesting Try...Catch Statements Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

Can you nest Try...Catch statements? Of course you can. But the only reason you may want to use Apress © 2003 (928 pages) nestedTry...Catch blocks is when you want to catch different types of exceptions. For example, say This text provides extensive coverage of ADO.NET technology one block is catching memory-related exceptions, one is catching Input/Output-related exceptions, and including ADO.NET internals, namespaces, classes, and one is catching database-related errors. In that case, nesting Try...Catch statements would be interfaces, and takes a comprehensive look at XML beneficial. namespaces and classes, and how to integrate both with ADO.NET.

However, you may not need to write nested statements. Actually, you can write multiple Catch statements with a single Try statement, which may solve the problem of handling multiple types of exceptions. But it Table of Contents doesn't mean you can't use nested statements. Applied ADO.NET—Building Data-Driven Solutions Introduction

Using Try with Multiple Catch Statements - ADO.NET Basics

Chapter 1

Chapter 2 - Data Components Visualyou Studio .NET multiple Catch statements for a Try statement. For TheTry...Catch statementinallows to write Chapter 3 you - ADO.NET in Disconnected Environments example, can catch memory, Input/Output (I/O), and database-related exceptions using a simple Try Chapter 4 - ADO.NET in Connected Environments statement. Chapter 5

- Handling ADO.NET Events Listing 69-5-shows how to use nested Try...Catch blocks and multiple Catch blocks. Chapter Integrating XML with ADO.NET Chapter 7


Chapter 8


Chapter 9


Listing 9-5: Using Nested Try...Catch and Multiple Catch Blocks

Imports Chapter 10 -System.IO Working with the ODBC .NET Data Provider Module Module1 Sub Main() Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Dim filename As String = "c:\\abc.txt" Chapter 13 - Developing a Custom Data Provider Dim Strings As New Collection() Chapter 14 - Developing Database Web Applications using ASP.NET ' start first try block here Chapter 15 - Using ADO.NET in Xml Web Services Try Chapter 16 - ASP.NET Server and Data Binding Dim Stream As Controls System.IO.StreamReader = _ Chapter 17 Building Real-World Web Applications File.OpenText(filename) Chapter 18 Object-Relational in .NET ' -start second Mapping Try block here Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Try Chapter 20 -While COM Interoperability and ADO.NET True Chapter 21 - Messaging Strings.Add(Stream.ReadLine()) Whileand ADO.NET: Notes on Performance Chapter 22 -End SQL Server Catch eosExp As System.IO.EndOfStreamException Appendix A - Relational Databases: Some Basic Concepts ' Write EndOfStream exception error Appendix B - Commonly Used SQL Statements Catch IOExp As System.IO.IOException Appendix C - ADO.NET Frequently Asked Questions ' IO Eception error Index Console.WriteLine(IOExp.Message) List of Figures Strings = Nothing List of Tables Finally List of Listings ' Close and dispose objects here List of Sidebars Stream.Close() End Try ' end second try bkock here Chapter 11 - Stored Procedures and Views

' catch of first Try block Catch exp As Exception Console.WriteLine(exp.Message) Finally ' Close and dispose objects here of first Try ' block here End Try ' end first try block here

End Sub End Module


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET. Using a Try...Catch block, you can even define your own custom filters and error messages. For

Defining Custom Filters and Error Messages

example,Listing 9-6 defines a filter that fires if the counter variable is 5 or greater and then generates a custom error message. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Listing 9-6: Defining a Custom Filter and Error Message


- ADO.NET Basics

Imports System.IO Chapter 2 - Data Components in Visual Studio .NET Module Module1 Chapter 3 - ADO.NET in Disconnected Environments Sub Main() Chapter 4 - ADO.NET in Connected Environments Dim filename As String = "c:\\abc.txt" Chapter 5 - Handling ADO.NET Events Dim counter As Int16 = 10 Chapter 6


ChapterTry 7 - Data Binding and Windows Forms Data-Bound Controls Chapter 8 Dim - Constraints Relations Stream and As Data System.IO.StreamReader = _ Chapter 9 File.OpenText(filename) - ADO.NET Exception Handling ChapterCatch 10 - Working the ODBC .NET Data Provider When with counter > 5 Chapter 11 - Stored Procedures and Views Console.WriteLine("Counter Out of Range") ChapterFinally 12 - Oracle, SQLXML, and Other .NET Data Providers

' -Close anda Custom dispose objects Chapter 13 Developing Data Provider here of first Try ' -block here Chapter 14 Developing Database Web Applications using ASP.NET ChapterEnd 15 -Try Using ADO.NET in Xml Web Services

End16Sub Chapter - ASP.NET Server Controls and Data Binding End Module Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

If you run the program, the output looks like Figure 9-3.


Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List ofFigure Listings9-3: The custom error message List of Sidebars

Appliedthe ADO.NET: Building Data-Driven Understanding Exception Classes Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

By now you probably have an (928 ideapages) of how to implement exception handling in your code. The following Apress © 2003 sections give a quick overview of the exception-related provided by the .NET Framework Library. This text provides extensive coverage ofclasses ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Using the Exception Class: Mother of All Exceptions TheException class represents errors that occur during application execution. This class is the base class for all exception classes. In the previous samples, you already saw how to create an object of the Table of Contents Exception class. Table 9-1 describes the Exception class properties. Applied ADO.NET—Building Data-Driven Solutions Introduction Table 9-1: Exception Class Properties Chapter 1

- ADO.NET Basics

Chapter 2


PROPERTY

DESCRIPTION

Chapter 3 - ADO.NET in Disconnected Environments HelpLink Represents the link to the help file associated with the exception (both get Chapter 4 - ADO.NET in Connected and set) Environments Chapter 5


Chapter 6


Chapter 7


InnerException

Returns the Exception instance that caused the current exception (get only)

Message Returns the error message that describes the current exception (read only) Chapter 8 - Constraints and Data Relations Chapter 9

Handling Source - ADO.NET Exception Represents the name of the application or object that caused the error (both get and set)


StackTrace Returns a string of the on the call stack at the time the exception Chapter 12 - Oracle, SQLXML, and Other .NET Dataframes Providers (read only) Chapter 13 - Developing a occurred Custom Data Provider Chapter 14 - Developing Database Applications ASP.NET TargetSite ReturnsWeb the method that using throws the exception (read only) Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

Understanding Other Exception Classes


Chapter 19 -Framework Mapped Objects: Considerations and Data Binding The .NET Class Performance Library defines many exception classes, and each of them is designed to Chapter - COM Interoperability andFor ADO.NET handle20 a specific kind of exception. example, an IOException error is thrown when an I/O error Chapter occurs.21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

TheSystemException class is Some the base class for system (runtime) errors. Some of the classes derived Appendix A - Relational Databases: Basic Concepts fromSystemException are StackOverflowException,ArithmeticException, ArrayTypeMismatchException,FormatException,IOException,OutOfMemory-Exception, Appendix C - ADO.NET Frequently Asked Questions RankException, and TypeLoadException. Appendix B - Commonly Used SQL Statements Index

List of .NET Figures The Framework Library defines hundreds of exception classes-some of which are specific to a List of Tables particular operation. For example, an OutOfMemory exception is thrown when there's not enough List of Listings memory to continue the execution of a program. Discussing all of the exception classes is beyond the List of Sidebars scope of this chapter.

Applied ADO.NET: Building Data-Driven Solutions Exception Handling in ADO.NET by Mahesh Chand and David Talbot

ISBN:1590590732

It's now time to talk about exception handling in ADO.NET. Each data provider provides three classes: Apress © 2003 (928 pages) Exception,Error, and ErrorCollection. For example, the technology SQL data provider provides the This text provides extensive coverage of ADO.NET SqlException,including SqlError, and SqlErrorCollection classes. You'll look at the ADO.NET-related ADO.NET internals, namespaces, classes, and takes a comprehensive look at XML classes and theninterfaces, you'll learnand how to implement a few of them in your code. namespaces and classes, and how to integrate both with

If you look at the ADO.NET. System.Data class hierarchy, you'll find many exception classes. These exception classes are accessible to all data providers through the System.Data namespace and the classes defined in this namespace. Table 9-2 briefly describes these classes. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Table 9-2: The System.Data Exception Classes

Introduction

Chapter 1 - ADO.NET Basics CLASS

DESCRIPTION

Chapter 2


Chapter 3


Chapter 4


ConstraintException

This class represents an exception thrown when attempting an operation that violates a constraint.

Chapter DataException 5 - Handling ADO.NET Events

This class is a base class for many database-related exception classes such as ContraintException, NoNullAllowException, and Chapter 7 - Data Binding and Windows Forms Data-Bound Controls MissingPrimaryKey-Exception. It's thrown Chapter 8 - Constraints and Data Relations when an error is generated using ADO.NET. Chapter 9 - ADO.NET Exception Handling Chapter 6


Chapter 10 - Working with the ODBC .NET Data Provider DBConcurrencyException This exception is a result of the DataAdapter's Chapter 11 - Stored Procedures and Views Update method when the affected rows after an Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Insert, Update, or Delete operation are zero Chapter 13 - Developing a Custom Data Provider because of the concurrency violation. Chapter 14 - Developing Database Web Applications using ASP.NET

DeleteRowInaccessibleException


This exception is thrown when a program tries to delete a DataRow that has already been deleted.


DuplicateNameException Chapter 17 - Building Real-World Web ApplicationsThis exception is thrown when a program tries to add a duplicate database object such as a table, relation, column, or a Data constraint to the database schema. Chapter 19 - Mapped Objects: Performance Considerations and Binding Chapter 18 - Object-Relational Mapping in .NET

Chapter 20 - COM Interoperability and ADO.NET EvaluateException

This exception is thrown when a program isn't able to evaluate the Expression property of a Chapter 22 - SQL Server and ADO.NET: Notes on DataColumn Performance object. Chapter 21 - Messaging


InRowChangingEventException


This exception is thrown when calling the EndEdit method within the RowChanging event.

Appendix C - ADO.NET Frequently Asked Questions Index InvalidConstraintException List of Figures List of Tables

InvalidExpressionException

List of Listings

List of Sidebars

This exception is thrown when a program tries to create an incorrect relation. This exception is thrown when attempting to add a DataColumn with an invalid Expression property value to a DataColumnCollection.

MissingPrimaryKeyException

This exception is thrown when trying to access a row in a table that has no primary key.

NoNullAllowedException

This exception is thrown when a program tries to insert a null value where the DataColumn's AllowDBNull property is False.

NoNullAllowedException

This exception is thrown when a program tries to change the value of a read-only column.

RowNotInTableException This exception is thrown when a program tries to Applied ADO.NET: Building Data-Driven Solutions perform an operation on a row that doesn't belong to ISBN:1590590732 by Mahesh Chand and David Talbot a table. Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology StrongTypingException This exception is thrown by a strongly typed including ADO.NET internals, namespaces, classes, DataSet when theand user accesses a DBNull value. interfaces, and takes a comprehensive look at XML

namespaces and classes, and how integrate is both with when the Expression SyntaxErrorException Thistoexception thrown ADO.NET. property of a DataColumn contains a syntax error.

TypedDataSetGeneratorException

Table of Contents


This exception is thrown when a name conflict occurs while generating a strongly typed DataSet.

This exception is thrown when a program tries to return a version of a DataRow that has been deleted. Chapter 2 - Data Components in Visual Studio .NET VersionNotFoundException Introduction Chapter 1

- ADO.NET Basics

Chapter 3


Chapter 4


- Handling SQL ADO.NET Events 2000 Errors Recognizing Server

Chapter 5 Chapter 6

- Integrating XML with ADO.NET Whenever run an invalid SQL query, SQL Server returns a formatted error message. Also, SQL Chapter 7 -you Data Binding and Windows Forms Data-Bound Controls

Server 8writes these error messages to the error log and/or event log. For instance, if you select records Chapter - Constraints and Data Relations

from a database table that doesn't exist, SQL Server will return an error message including the message - ADO.NET Exception Handling ID, severity level, error state, line number, and the error message. For example, if you execute the Chapter 10 - Working with the ODBC .NET Data Provider following SQL query: Chapter 9



select * from SomeTable

Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Usingdoesn't ADO.NET in in Xml Servicesthen SQL Server will return an error that looks like the butSomeTable exist theWeb database, Chapter 16 ASP.NET Server Controls and Data Binding following: Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Server: Msg 208, Level 16, State 1, Line 1

Chapter 19 -object Mapped Objects: Performance Considerations and Data Binding Invalid name 'SomeTable'. Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

The first of the error is the error message Each error message has an associated error Chapter 22part - SQL Server and ADO.NET: Notes on number. Performance messageA number thatDatabases: uniquely identifies the Concepts error. Error messages number from 1 to 49,999 are reserved Appendix - Relational Some Basic for SQL BServer. You can also define your own custom error messages, but your message number must Appendix - Commonly Used SQL Statements be fall between 50,000 and 2,147,483,647. Appendix C - ADO.NET Frequently Asked Questions Index

The second part of the message is the error severity level, which falls between 0 and 25. The error severity represents the nature of the error. Table 9-3 describes the severity levels.


List of Listings Table 9-3: Severity Levels List of Sidebars

RANGE


0-10

These messages are not actual errors. These messages are used only for Apress © 2003 (928 pages) informational purposes.

11-16

including internals, namespaces, classes, and Severity levelsADO.NET 11-16 are generated because of user problems and can be fixed by the and takes a comprehensive look atinXML user.interfaces, For example, the error message returned the invalid Update query, used namespaces and classes, and how to integrate both with earlier, had a severity level of 16. ADO.NET.

17

SQL Server has run out of a configurable resource, such as locks.

by Mahesh Chand and David Talbot

ISBN:1590590732


Table 18 of Contents Represents nonfatal internal software problems. Applied ADO.NET—Building Data-Driven Solutions

19 A nonconfigurable resource limit has been exceeded. Introduction Chapter 20 1 Chapter 2

- ADO.NET Basics Represents a problem with a statement issued by the current process. - Data Components in Visual Studio .NET

Chapter 3


Chapter 22 4 Chapter 5

- ADO.NET in Connected Represents a table or Environments index that has been damaged. - Handling ADO.NET Events

Chapter 6


Chapter 24 7

- Data Binding a and Windowsproblem. Forms Data-Bound Controls Represents hardware

Chapter 8


Chapter 9


21

23

25

SQL Server has encountered a problem that affects all the processes in a database.

Represents a suspect database.

Represents some type of system error.

Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 Severity - Stored level Procedures Note errors and thatViews fall between 19 and 25 are fatal errors and can only be used via Chapter 12 RAISERROR - Oracle, SQLXML, and Other Datadatabase Providers role sysadmin with the with log option by members of .NET the fixed Chapter 13 required. - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

The next of SQL Server message is the state number, which varies from 1 to 127; it represents Chapter 15part - Using ADO.NET in error Xml Web Services information about theServer source that issued the error. Chapter 16 - ASP.NET Controls and Data Binding Chapter 17 - Building Real-World Web Applications

The line portion of the error message represents the source line where the actual error occurred.


Chapter The last 19part - Mapped of the error Objects: message Performance is the error Considerations description. andThe Data SQL Binding Server error messages are stored in

the sysmessages system table. To all the messages from this table, you can run the following SQL Chapter 20 - COM Interoperability andread ADO.NET query in21the Query Analyzer: Chapter - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix selectA *- Relational from sysmessages Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index

Using SQL Server Error Logs


SQL List of Server Listings maintains an error log (in text format) that stores the server information and error messages. Error log files can help you track down problems or alert you to potential or existing problems. The SQL List of Sidebars Server log files are stored in the LOG folder of the SQL Server home folder. This folder has more than one log file (usually seven), and the first of them is ERRORLOG. By default there's no extension to these files. To see their contents, you need to add a .txt extension to the file. Note that you may not be able to change the name of the log file if SQL Server is running. So, stop SQL Server before modifying or reading the log file. The partial contents of ERRORLOG looks like the following: 2002-10-27 13:32:00.57 server Microsoft SQL Server 2000 - 8.00.194 (Intel X86) Aug 6 2000 00:57:48 Copyright (c) 1988-2000 Microsoft Corporation Personal Edition on Windows NT 5.0 (Build 2195:

Service Pack 3) Applied ADO.NET: Building Data-Driven Solutions 2002-10-27 13:32:00.79 server ISBN:1590590732 by Mahesh Chand and David Talbot Copyright (C) 1988-2000 Microsoft Corporation. Apress © 2003 (928 pages) 2002-10-27 13:32:00.79 server This text provides extensive coverage of ADO.NET technology All rights reserved. including ADO.NET internals, namespaces, classes, and 2002-10-27 13:32:00.79 server interfaces, and takes a comprehensive look at XML Server Process ID is 596. namespaces and classes, and how to integrate both with 2002-10-27 13:32:00.79 server ADO.NET. Logging SQL Server messages in file 'D:\Program Files\Microsoft SQL Server\MSSQL\log\ERRORLOG'. Table of Contents 2002-10-27 13:32:00.97 server Applied ADO.NET—Building Data-Driven Solutions class 'normal'(1 CPU detected). SQL Server is starting at priority Introduction 2002-10-27 13:32:02.43 server Chapter 1 - ADO.NET Basics SQL Server configured for thread mode processing. Chapter 2002-10-27 2 - Data 13:32:02.57 Components in server Visual Studio .NET Using3 dynamic lock allocation. Chapter - ADO.NET in Disconnected Environments [500]4 Lock Blocks, [1000]Environments Lock Owner Blocks. Chapter - ADO.NET in Connected 2002-10-27 13:32:02.95 spid3 Chapter 5 - Handling ADO.NET Events …… 6 - Integrating XML with ADO.NET Chapter Chapter 7


Chapter 8


SQL Server also adds error messages to the Windows NT event log. You can use the Windows NT Event - ADO.NET Exception Handling Viewer to view the error messages. The Windows NT Event Viewer is located in the Windows NT Chapter 10 - Working the ODBC .NET Data Provider Administrative Toolswith group. Chapter 9


Using the SqlException Class


Chapter 14 - Developing Database Webwhen Applications using ASP.NET TheSqlException class is thrown SQL Server returns a warning or error. The SqlException Chapter 15 Using ADO.NET in Xml Web Services class is inherited from the SystemException class, which in turn is inherited from the Exception class. Chapter - ASP.NET Server Controls and Data Besides16the Exception class members, the Binding SqlException class defines the properties described in Chapter 17 Building Real-World Web Applications Table 9-4. Chapter 18 - Object-Relational Mapping in .NET Chapter Table 9-4: 19 - The Mapped SqlException Objects: Performance Class Properties Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

PROPERTY

DESCRIPTION


Chapter 22 - SQL Server and ADO.NET: Notes Class Returns the severity levelon ofPerformance the error. Appendix A - Relational Databases: Some Basic Concepts

Returns a collection of one or more SqlError objects. This property is used when you need to collect more information about the errors generated by the Appendix C - ADO.NET Frequently Asked Questions Sql data provider. Errors

Appendix B - Commonly Used SQL Statements Index

List of Tables

Returns the line number within the SQL command or stored procedure that generated the error.

ListMessage of Listings

Represents human-readable text of the error.

ListLineNumber of Figures

List of Sidebars

Number

Returns a number that identifies the type of error.

Procedure

Represents the name of the stored procedure that generated the error.

Server

Represents the name of the computer running SQL Server.

Source

Returns the name of the provider.

State

Numeric error code from SQL Server that represents an error or warning.

OK, now you'll see the SqlException class in action. Listing 9-7 connects to a SQL Server called MCB, reads data from the Customers table, and then fills a DataSet.

Listing 9-7: Reading Data from a SQL Server


ISBN:1590590732

' Create a Connection Object Apress © 2003 (928 pages) Dim ConnectionString As String ="Integrated Security=SSPI;" & _ This text provides extensive coverage of ADO.NET technology "Initial includingCatalog=Northwind;Data ADO.NET internals, namespaces,Source=MCB;" classes, and Dim conn interfaces, As SqlConnection = New SqlConnection(ConnectionString) and takes a comprehensive look at XML namespaces classes, and*how to integrate both with Dim SQL As String and = "SELECT FROM Customers" ADO.NET. Dim adapter As SqlDataAdapter = New SqlDataAdapter(SQL, conn) Dim ds As DataSet = New DataSet() Table of Contents

Try ' open a connection Introduction conn.Open() Chapter 1 - ADO.NET Basics adapter.Fill(ds, "Customers") Chapter 2 - Data Components in Visual Studio .NET Catch exp As SqlException Chapter 3 - ADO.NET in Disconnected Environments ' Generate error message Chapter 4 Console.WriteLine("Error:" - ADO.NET in Connected Environments + exp.Message & _ Chapter 5 ",- Handling ADO.NET Events Number:" + exp.Number.ToString() & _ Chapter 6 ",- Integrating XML with Line Number: " ADO.NET + exp.LineNumber.ToString() & _ Chapter 7 ",- Data Binding and Windows Forms Data-Bound Controls Server:" + exp.Server.ToString() & _ Chapter 8 ", - Constraints and+Data Relations Source:" exp.Source.ToString()) ChapterFinally 9 - ADO.NET Exception Handling ' -Close connection Chapter 10 Workingthe with the ODBC .NET Data Provider If- Stored conn.State = and ConnectionState.Open Then Chapter 11 Procedures Views Chapter 12 -conn.Close() Oracle, SQLXML, and Other .NET Data Providers End If Chapter 13 - Developing a Custom Data Provider ' Dispose connection Chapter 14 - Developingthe Database Web Applications using ASP.NET If (Not conn Is Nothing) Then Chapter 15 - Using ADO.NET in Xml Web Services conn.Dispose() Chapter 16 - ASP.NET Server Controls and Data Binding End If Chapter 17 - Building Real-World Web Applications End Try Applied ADO.NET—Building Data-Driven Solutions


Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Now change the SQL Server name to MCB1. The connection string looks like following: Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Basic Dim ConnectionString As Some String = Concepts "Integrated Security=SSPI;" & _ Appendix B - Commonly SQL Statements "InitialUsed Catalog=Northwind;Data Source=MCB1;" Appendix C - ADO.NET Frequently Asked Questions Index

If you run the code after changing the SQL Server name, it generates an error that looks like Figure 9-4. List of Figures List of Tables List of Listings List of Sidebars

Figure 9-4: SqlException messages for SQL Server not found Now let's switch the SQL Server to MCB and change the SQL string to the following: Dim SQL As String = "SELECT * FROM Test"

The output looks like Figure 9-5.


ISBN:1590590732


Figure 9-5: SqlException messages when a database table not found Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Using the SqlError and SqlErrorCollection Classes


- ADO.NET Basics

Chapter 5


TheSqlException.Errors property returns an object of SqlErrorCollection class. This object is Chapter 2 - Data Components in Visual Studio .NET a collection of SqlError objects, each of which encapsulates an error or warning by SQL Server. The Chapter 3 - ADO.NET in Disconnected Environments Count property of SqlErrorCollection returns the total number of errors in a collection, and the Chapter 4 - ADO.NET in Connected Environments Item property returns an error at the specified index. Chapter 6 - property Integrating with ADO.NET TheClass of XML SqlError represents the severity level of the error, which varies from 0 to 25. Chapter 7 Data Binding and Windows Even using the severity level, you can Forms notify aData-Bound user of theControls results of the error. Chapter 8

- Constraints and Data Relations Messages a severity level starting Chapter 9 -with ADO.NET Exception Handlingfrom 0 to 10 are informational and indicate a nonfatal error. Severity

levels from 11 to 16 indicate a user error that can be corrected by the user. Severity levels from 17 to 25 indicate software or hardware errors, but the program can continue working. Severity level 20 or more Chapter 11 - Stored Procedures and Views indicates serious fatal errors and may cause damage. Chapter 10 - Working with the ODBC .NET Data Provider


Chapter Developing a Customand DataSqlErrorCollection Provider Listing 13 9-8-uses the SqlError classes and handles the errors generated by Chapter - Developing the Sql14 data provider. Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Listing16 9-8: Using the SqlError Objects Chapter - ASP.NET Server Controls and and SqlErrorCollection Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 -System.Data.SqlClient Object-Relational Mapping in .NET Imports Chapter Module 19 Module1 - Mapped Objects: Performance Considerations and Data Binding

Sub20Main() Chapter - COM Interoperability and ADO.NET Create a Connection Object Chapter'21 - Messaging As Notes String = "Integrated Security=SSPI;" & _ ChapterDim 22 -ConnectionString SQL Server and ADO.NET: on Performance "Initial Catalog=Northwind;Data Source=MCB;" Appendix A - Relational Databases: Some Basic Concepts Dim As SqlConnection = New SqlConnection(ConnectionString) Appendix B -conn Commonly Used SQL Statements Dim SQL As String = "SELECT * FROM Test" Dim adapter As SqlDataAdapter = New SqlDataAdapter(SQL, conn) Index Dim ds As DataSet = New DataSet() Appendix C - ADO.NET Frequently Asked Questions List of Figures List of Tables

Try ' open a connection List of Sidebars conn.Open() adapter.Fill(ds, "Customers") Catch exp As SqlException ' Generate error message Dim errs As SqlErrorCollection = exp.Errors Dim i As Integer Dim err As SqlError For Each err In errs Console.WriteLine("Error #:" & i.ToString() & _ ", Class:" & err.Class.ToString() & _ ", Line Number :" & err.LineNumber & _ ", Message:" & err.Message & _ List of Listings

", Source:" & err.Source & _ Applied ADO.NET: &Building Data-Driven Solutions ", Server:" err.Server) ISBN:1590590732 by Mahesh Chand and David Talbot Next Finally Apress © 2003 (928 pages) ' Close the connection This text provides extensive coverage of ADO.NET If conn.State = ConnectionState.Open Then technology including ADO.NET internals, namespaces, classes, and conn.Close() interfaces, and takes a comprehensive look at XML End If namespaces and classes, and how to integrate both with ' Dispose the connection ADO.NET. If (Not conn Is Nothing) Then conn.Dispose() Table of Contents End If AppliedEnd ADO.NET—Building Data-Driven Solutions Try Introduction End Sub Chapter 1 - ADO.NET Basics End Module

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Summary


ISBN:1590590732

In this chapter, you learned about exception handling. You saw how exception handling works in .NET, and Apress © 2003 (928 pages) you learned how This to handle exceptions in ADO.NET. text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

ODBC .Net data provider classes work with ODBC data sources. interfaces, and takes a comprehensive look at XML The good thing about ODBC connectivity namespaces and classes, and data how sources to integrate both as with is that an application can connect to multiple as long it has an ODBC driver for the data ADO.NET. source. In next chapter, you'll learn about the ODBC .Net data provider, and you'll learn how to write applications that access various data sources. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 10: Working with the ODBC .NET Data ISBN:1590590732 by Mahesh Chand and David Talbot ProviderApress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, classes, and with SQL Server databases. You In previous chapters, you saw how to use the namespaces, Sql data provider to work interfaces, and takes a comprehensive look at XML also learned that namespaces there aren't and great differences between any of the data providers. With a few minor classes, and how to integrate both with exceptions, it's just a matter of changing class names and the connection string. You don't believe us? To ADO.NET. prove this theory, you'll see how to use the ODBC data provider in this chapter.

The of ODBC data provider uses ODBC drivers to connect to different data sources; it's useful when you're Table Contents not sure what database your clients will be using in their applications. The user shouldn't have any trouble Applied ADO.NET—Building Data-Driven Solutions connecting as long as they have an ODBC driver for the database installed on their machine. In this Introduction chapter, see how you can use the ODBC .NET data provider to work with MySQL, Oracle, Excel, and Chapter 1 you'll - ADO.NET Basics even text files. Chapter 2 data - Data Components in Visual Studio .NET Chapter 3


Using the ODBC .NET Environments Data Provider - ADO.NET in Connected

Chapter 4 Chapter 5


You read a- brief discussion about the ODBC .NET data provider in Chapter 4. The ODBC .NET data Integrating XML with ADO.NET provider provides access to ODBC data sources with the help of native ODBC drivers in the same way that Chapter 7 - Data Binding and Windows Forms Data-Bound Controls the OleDb data provider accesses native OLE DB providers. One of the best things about working with Chapter 8 - Constraints and Data Relations ADO.NET data providers is that all the data providers define a similar class hierarchy. The only things you Chapter 9 - ADO.NET Exception Handling need to change are the classes and the connection string. Chapter 6


Chapter Stored Procedures and .NET Viewsdata provider, let's quickly look at some installation issues. Before 11 you- start using the ODBC Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Note usinga Visual .NET (VS .NET) code name Everett, you don't need to worry about Chapter 13 If- you're Developing CustomStudio Data Provider

installation because the ODBC .NET data provider is already installed.You can skip the following section.



Installing the ODBC .NET Data Provider


Unlike the Sql and OleDb data providers, the ODBC data provider is an add-on component to the .NET Framework. If the ODBC .NET provider isn't installed on your system, you can download it from the .NET Chapter 20 - COM Interoperability and ADO.NET Software Development Kit (SDK) and VS .NET on the Microsoft site (www.microsoft.com/data). Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 21 - Messaging

Chapter 22 Microsoft - SQL Server and ADO.NET: Notes on Performance Note VS .NET code name Everett installs the ODBC .NET data provider automatically. Appendix A - Relational Databases: Some Basic Concepts

After installing the ODBC data you need to customize the Toolbox to add the ODBC data Appendix B - Commonly Used SQLprovider, Statements components to it. YouFrequently can customize Toolbox by right-clicking the Data tab and selecting Customize Appendix C - ADO.NET Asked the Questions Toolbox.

Index

List ofNote Figures Make sure the Data tab is selected when you choose Customize Toolbox. Otherwise, new List of Tables components will be added to the active tab. List of Listings

Next, click the .NET Framework Components tab (not the default COM components) and look for the List of Sidebars ODBC components. Check the appropriate boxes, and then click the OK button. These check boxes are OdbcCommand,OdbcCommandBuilder,OdbcConnection, and OdbcDataAdapter. Next, you need to add a reference to the Microsoft.Data.Odbc.dll assembly using Project Ø Add Reference. You can use the Browse button to browse the directory. The Microsoft.Data.Odbc.dll assembly resides in the \Program Files\Microsoft.NET\Odbc.NET directory. On the Add Reference dialog box, select Microsoft.Data.Odbc.dll and then click the OK button, which adds the Microsoft.Data.Odbc namespace reference to the project. You can see the namespace reference by expanding the References node of your project in the Server Explorer. To make sure the ODBC data provider is installed and added to your project, you can also look at the Toolbox. If the ODBC data provider is installed on your machine, the Toolbox will display the ODBC data

components.


ISBN:1590590732 by Mahesh Chand and available David Talbot Note The Toolbox's Data tab isn't for console applications. However, you can use ADO.NET Apress © 2003 (928 pages) by writing the code manually. in console-based applications


You saw how to use the SQL and OleDb datanamespaces, providers inclasses, previousand chapters. Working with the ODBC data including ADO.NET internals, interfaces, takeswith a comprehensive look atdata XML providers. Unlike the Sql and OleDb data provider is no different fromand working the Sql and OleDb namespaces and classes, andishow to integrate both with providers, however, the ODBC data provider defined in the Microsoft.Data.Odbc namespace. You ADO.NET. must add the following reference to this namespace before you can start using the ODBC data provider classes: Table of Contents Applied Imports ADO.NET—Building Microsoft.Data.Odbc Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Note If you're using Microsoft VS .NET code name Everett, the ODBC data provider is defined in the - ADO.NET in Disconnected Environments System.Data.Odbc namespace. Make sure you import the correct namespace.

Chapter 3 Chapter 4


Chapter 5


Understanding thewith ODBC - Integrating XML ADO.NET.NET Data Provider

Chapter 6 Chapter 7


The ODBC data provider defines similar classes and a similar class hierarchy as the Sql and OleDb data Chapter 8 - Constraints and Data Relations providers. Further, you can use the ODBC data provider classes the same way as you've used the Sql and Chapter 9 - ADO.NET Exception Handling OleDb data provider classes. Table 10-1 defines the ODBC data provider classes. Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

Table 10-1: The ODBC .NET Data Provider Classes


CLASS Chapter 13 - Developing a Custom DataDESCRIPTION Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Similar to OleDbCommand and SqlCommand, this class represents an SQL statement or stored procedure to execute Chapter 16 - ASP.NET Server Controls and Data Binding against a data source. OdbcCommand



OdbcCommandBuilder Chapter 18 - Object-Relational Mapping Similar in .NET to OleDbCommandBuilder and SqlCommandBuilder, thisBinding class automatically generates Chapter 19 - Mapped Objects: Performance Considerations and Data SELECT,INSERT,UPDATE, and DELETE SQL commands.

Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging OdbcConnection

Represents a connection.


OdbcDataAdapter

Represents a DataAdapter.


Appendix B - Commonly Used SQL Statements OdbcDataReader Represents a DataReader. Appendix C - ADO.NET Frequently Asked Questions

OdbcError

Index

ListOdbcErrorCollection of Figures List of Tables

OdbcException

List of Listings

ListOdbcParameter of Sidebars

Represents errors and warnings. Represents a collection of errors and warnings. Represents an ODBC Exception class. Represents an ODBC parameter.

OdbcParameterCollection

Represents a parameter collection.

OdbcTransaction

Represents a transaction.

As you can see from Table 10-1, the ODBC data provider has many classes that are similar to the Sql and OleDb data providers. To use the ODBC data provider classes, you create a Connection object and then fill data from the Connection object to a DataAdapter or a DataReader, and they display the data.

ADO.NET: Building Data-Driven Solutions Accessing Applied Access Databases by Mahesh Chand and David Talbot

ISBN:1590590732

Now you'll see anApress example of (928 howpages) to access data from a data source using the ODBC data provider. In this © 2003 example, you'll use the Access 2000 Northwind database as the data source. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

Before creating ainterfaces, connection, the firstathing you need to setatis XML the connection string. The connection string and takes comprehensive look for OdbcConnection namespaces contains anda classes, data source and how driver to and integrate the data bothsource with path with an optional user ID and ADO.NET. password. Optionally, you can also use an ODBC Data Source Name (DSN) as the connection string. You create a DSN from the ODBC Administration applet in the Windows Control Panel. Table of Contents

The connection string for an Oracle database looks like the following:


Driver={Microsoft ODBC for Oracle};Server=ORACLE8i7;UID=odbcuser;PWD=odbc$5xr

Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3 - ADO.NET Disconnected The connection stringinfor a Microsoft Environments Access database looks like the following: Chapter 4 - ADO.NET in Connected Environments Chapter 5 - Handling ADO.NET Events Driver={Microsoft Access Driver (*.mdb)};DBQ=c:\\Northwind.mdb Chapter 6 - Integrating XML with ADO.NET Chapter 7


The connection string for anData Excel database looks like the following: Chapter 8 - Constraints and Relations Chapter 9


Chapter Driver={Microsoft 10 - Working with Excel the ODBC Driver .NET Data (*.xls)};DBQ=c:\bin\book1.xls Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

The connection string for a text database looks like the following:



Driver={Microsoft Text Driver (*.txt; *.csv)};DBQ=c:\\ Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

You can use any DSN by using the following connection string:



DSN=dsnname

Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL string Serverfor and Notes on Performance The connection a ADO.NET: SQL Server database looks like following: Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements "DRIVER={SQL Server};SERVER=MyServer;UID=sa;PWD=Qvr&77xk;DATABASE=northwind;"; Appendix C - ADO.NET Frequently Asked Questions Index

Listing 10-1 reads data from the Northwind database and shows the results on the console. For this List of Figures example, create a console application to test the code. As you can see from Listing 10-1, first you import the List of Tables Microsoft.Data.Odbc namespace. After that you create an OdbcConnection object with the List of Listings Microsoft Access ODBC driver and the Northwind database. The next step is to create an OdbcCommand List of Sidebars

object and call the ExecuteReader method, which returns an OdbcDataReader object. Finally, you read data from the DataReader and display the results on the console. Listing 10-1: Reading Data from Northwind Using the ODBC Data Provider Imports Microsoft.Data.Odbc Module Module1 Sub Main() ' Build a connection and SQL strings Dim connectionString As String = _ "Driver={Microsoft Access Driver (*.mdb)};DBQ=c:\\Northwind.mdb"

Dim SQL As String _ ADO.NET: FirstName, Building Data-Driven Solutions = "SELECTApplied EmployeeID, LastName FROM Employees" ISBN:1590590732 by Mahesh Chand and David Talbot ' Create connection object © 2003 (928 pages) Dim conn Apress As OdbcConnection = New OdbcConnection(connectionString) This text provides extensive coverage of ADO.NET technology ' Create command object including ADO.NET internals, classes, and Dim cmd As OdbcCommand = New namespaces, OdbcCommand(SQL) interfaces, and takes a comprehensive look at XML cmd.Connection = conn namespaces and classes, and how to integrate both with ' Open connection ADO.NET. conn.Open() ' Call command's ExecuteReader Table of Contents Dim reader As OdbcDataReader = cmd.ExecuteReader() Applied'ADO.NET—Building Data-Driven Solutions results on the console Read the reader and display Introduction Console.WriteLine("Employeed ID, First Name, Last Name ") ChapterWhile 1 - ADO.NET Basics reader.Read() Chapter 2 Console.Write(reader.GetInt32(0).ToString()) - Data Components in Visual Studio .NET ") Environments Chapter 3 Console.Write(", - ADO.NET in Disconnected Chapter 4 Console.Write(reader.GetString(1).ToString()) - ADO.NET in Connected Environments ") Chapter 5 Console.Write(", - Handling ADO.NET Events Chapter 6 Console.WriteLine(reader.GetString(2).ToString()) - Integrating XML with ADO.NET ChapterEnd 7 -While Data Binding and Windows Forms Data-Bound Controls ' close reader and connection Chapter 8 - Constraints and Data Relations reader.Close() Chapter 9 - ADO.NET Exception Handling conn.Close() Chapter 10 - Working with the ODBC .NET Data Provider conn.Dispose() Chapter 11 - Stored Procedures and Views End Sub Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers End Module Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - of ASP.NET Controls Data Binding The output Listing Server 10-1 looks like and Figure 10-1. As you can see, the program reads the EmployeeID, Chapter FirstName, 17 - and Building LastName Real-World fields Web from Applications Employees table. Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List ofFigure Tables 10-1: The output of Listing 10-1 List of Listings List of Sidebars

ADO.NET: Building Data-Driven Solutions Accessing Applied MySQL Databases by Mahesh Chand and David Talbot

ISBN:1590590732

MySQL is a widely used,©multithreaded, Apress 2003 (928 pages) multiuser, robust SQL database server. You can use MySQL for free under the GNU General Publicextensive License.coverage You canofdownload MySQL database and its tools from This text provides ADO.NETthe technology www.mysql.com/downloads/index.html. After downloading the including ADO.NET internals, namespaces, classes, and zipped file, you unzip it in a folder interfaces, and takes a comprehensive look at XML and run Setup.exe. By default the setup file installs MySQL in your C:/mysql folder. The namespaces and classes, and how to integrate both with Documentation section (www.mysql.com) has detailed instructions on how to install and register the ADO.NET. MySQL server and its services. Note You may need Administrator rights to install and register the MySQL server and its services.

Table of Contents

Applied ADO.NET—Building Data-Driven After installing MySQL, make sure it'sSolutions running. If the service isn't running, you may need to start it Introduction manually. You can start it by selecting Control Panel Ø Administrative Tools Ø Services, right-clicking the Chapter 1 - ADO.NET Basics MySql service, and then selecting the Start menu option. This action will start MySql as a service. Because Chapter 2 - Data Components VisualtoStudio .NET in this chapter you'll be using in ODBC connect to a MySQL database, you need to install an ODBC driver Chapter 3 -can ADO.NET Disconnected Environments for it. You find theinmost widely used ODBC driver for MySQL, MyODBC, at

www.mysql.com/downloads/api-myodbc.html. Chapter 4 - ADO.NET in Connected Environments Chapter 5


After downloading the zipped driver file, the obvious action is to unzip it and install it. If the driver is installed - Integrating XML with ADO.NET properly, you can see it from the ODBC Data Source Administrator by selecting Control Panel Ø Data Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Source (ODBC). You must see MySQL in the ODBC Drivers list to proceed. Chapter 6 Chapter 8


Chapter 9 program, - ADO.NET Exception For your you can useHandling any MySQL database you have on the server, but for this example, use the Chapter 10 -database. Working with the ODBC Northwind You've never .NET heardData of aProvider MySQL version of the Northwind database, you say? Well, Chapter 11 -one. Stored Procedures andAccess Views Northwind database to MySQL and then you'll use it. there isn't You'll convert the Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

To convert import) athe Access Northwind Chapter 13 - (or, Developing Custom Data Provider database, you can use a free tool called DBTools Manager. This tool provides many handy functions for MySQL developers. You can download DBTools at www.dbtools.com.br.



ADO.NET: Building Data-Driven Solutions Accessing Applied MySQL Databases by Mahesh Chand and David Talbot

ISBN:1590590732

As we've been saying, with different data sources is only a matter of changing the connection Apressworking © 2003 (928 pages) string and class names. You can access a MySQL database either using a DSN or using the database This text provides extensive coverage of ADO.NET technology name directly in the connection string. You can use a database name including ADO.NET internals, namespaces, classes, and directly, as shown in the following interfaces, and takes a comprehensive look at XML code: namespaces and classes, and how to integrate both with ADO.NET.

dim connectionString as string = "Driver={MySQL};SERVER=localhost;DATABASE=NorthwindMySQL;" Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction

Or you 1can- use an ODBC Chapter ADO.NET BasicsDSN, as you can see from the following code that uses TestDSN to connect to the data Chapter 2 source: - Data Components in Visual Studio .NET Chapter 3

- ADO.NET in Disconnected Environments Dim conn as OdbcConnection = new OdbcConnection("DSN=TestDSN") Chapter 4 - ADO.NET in Connected Environments Chapter 5


Chapter 6


To test this code, create a Windows application, add a DataGrid control to the form, and then write the - Data Binding and Windows Forms Data-Bound Controls code in Listing 10-2 on the Form_Load event. As you can see in Listing 10-2, this code is similar to the Chapter 8 saw - Constraints Data Relations code you in Listingand 10-1. It creates a Connection object, a DataAdapter, fills the DataSet from Chapter 9 ADO.NET Exception Handling theDataAdapter, and then sets the DataSet'sDefaultViewManager as the DataGrid control's Chapter 10 - Working with the ODBC .NET Data Provider DataSource property. Chapter 7


Listing12 10-2: Accessing a MySQL Database Chapter - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 -Sub Developing Database Web Applications ASP.NET Private Form1_Load(ByVal sender using As System.Object, _ Chapter 15 -eUsing in Xml Web Services ByVal As ADO.NET System.EventArgs) Handles MyBase.Load ChapterDim 16 -connectionString ASP.NET Server ControlsAs andString Data Binding = _ Chapter"Driver={MySQL};SERVER=localhost;DATABASE=NorthwindMySQL;" 17 - Building Real-World Web Applications

As OdbcConnection = New OdbcConnection(connectionString) ChapterDim 18 -conn Object-Relational Mapping in .NET Chapterconn.Open() 19 - Mapped Objects: Performance Considerations and Data Binding

OdbcDataAdapter = New OdbcDataAdapter _ ChapterDim 20 -da COMAs Interoperability and ADO.NET CustomerID, ContactName, ContactTitle FROM Customers", conn) Chapter("SELECT 21 - Messaging DataSet = NewNotes DataSet("Cust") ChapterDim 22 -ds SQLAs Server and ADO.NET: on Performance da.Fill(ds, "Customers") DataGrid1.DataSource = ds.DefaultViewManager Appendix B - Commonly Used SQL Statements conn.Close() Appendix C - ADO.NET Frequently Asked Questions conn.Dispose() Index End Sub Appendix A - Relational Databases: Some Basic Concepts



ADO.NET: Building Data-Driven Solutions Accessing Applied Text File Databases by Mahesh Chand and David Talbot

ISBN:1590590732

To test text database connectivity, you can export the Employees table of the Northwind database using Apress © 2003 (928 pages) the File Ø ExportThis option of Access 2000. In the following section, you'll export a table to a text file, and text provides extensive coverage of ADO.NET technology you'll see how to including use it withADO.NET the ODBC DataAdapter. internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Exporting an Access Table to a Text File

You can export an Access database table to a text file using the Export option. In other words, select a Table Contents tableofand choose File Ø Export. Another option is to rightclick a table and choose the Export option from Applied ADO.NET—Building Data-Driven Solutions the menu. Introduction

After clicking the Export option, the dialog box that appears lets you pick a path and the file you want to Chapter 1 - ADO.NET Basics export. There are many export formats available. For this example, select the Text Files option. - Data Components in Visual Studio .NET

Chapter 2

Chapter 3 Export - ADO.NET Disconnected Next, the Text in Wizard lets youEnvironments define the format of the text file-either delimited or fixed width (see Chapter 4 ADO.NET in Connected Environments Figure 10-2). Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Figure 10-2: Export Text Wizard options


Chapter 22also - SQL Server and ADO.NET: Notes on more Performance You can click the Advanced button to set options, such as specifying the delimiters and other Appendix options (see A - Relational Figure 10-3). Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 10-3: The advanced options of the Export Text Wizard

The next screen lets you pick the delimiter, including a comma, tab, semicolon, space, and others. Figure Applied ADO.NET: Building Data-Driven Solutions 10-4 shows the Comma option checked. by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5

- Handling ADO.NET Events Figure Delimiter of the Export Text Wizard Chapter 6 - 10-4: Integrating XML options with ADO.NET Chapter 7


Chapter 9


Figure 10-4 also shows the Include Field Names on First Row check box selected. This option adds the Chapter 8 - Constraints and Data Relations first row of the text file as field names. Chapter 10page - Working theasks ODBC .NET Provider of where you want to export the data. Enter the The last of the with wizard you forData the filename Chapter 11C:\Employees.txt. - Stored Procedures and Views filename Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Finally,13 click the Finish abutton. When wizard is done exporting, you'll see a message saying the export Chapter - Developing Custom Data the Provider is finished. OK and close Access. Chapter 14 -Click Developing Database Web Applications using ASP.NET Chapter 15 -C:\Employees.txt, Using ADO.NET in Xml Web Services If you view it looks like Figure 10-5. Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - 10-5: ADO.NET Frequently Asked Questions Figure Exported Employees.txt file from Nothwind.mdb Index List of Figures List of Tables

Accessing a Text File

List of Listings

List of can Sidebars You access a text file using the ODBC data provider. There are two ways to access text files: You can

create a DSN from the ODBC Data Source Administrator, or you can access the text file directly from your application. To create a data source for a text file, go to ODBC Data Source Admin, click the New button (or the Add button if you're using Windows XP), and select the Microsoft Text Driver (*.txt, *.csv) option (see Figure 10-6).


ISBN:1590590732


Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1 - 10-6: ADO.NET Basics the Microsoft Text Driver (*.txt, *.csv) option Figure Selecting Chapter 2 - Data Components in Visual Studio .NET Chapter 3


You define the DSN name and description in the ODBC Text Setup dialog box. If you don't want to use the - ADO.NET in Connected Environments current directory, uncheck the Use Current Directory option to enable the Select Directory button and click Chapter 5 - Handling ADO.NET Events Options to see more options (see Figure 10-7). Chapter 4 Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure 10-7: Setting the DSN name and description

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix - Relational Databases: BasictoConcepts Now youAcan select any directorySome you want use. An entire text file is used as a database table (see Appendix B - Commonly Used SQL Statements Figure 10-8). Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 10-8: Selecting the directory and file types You can even define different formats by using the Define Format button in the ODBC Text Setup dialog box. As you can see from Figure 10-9, all files are treated as a database table. From the Format dropdown box, you can select the type of format you want such as comma delimited or tab delimited. The Guess button assigns the column names for you. If it doesn't find a proper format file, it creates F1...Fn

columns for you. You can also add, modify, and remove columns and their types. Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Figure 10-9: Defining a text file format and column settings

Chapter 5 - Handling After creating a DSN,ADO.NET you can Events use it as a connection source for your connection: Chapter 6 - Integrating XML with ADO.NET Chapter 7 - Data Binding and Windows =Forms Controls Dim conn As OdbcConnection New Data-Bound OdbcConnection("DSN=TxtDSN") Chapter 8 - Constraints and Data Relations Chapter 9

- ADO.NET Exception Handling Another10way to access is directly using the text ODBC driver in the connection string. For Chapter - Working withtext thefiles ODBC .NET Data Provider

example, in Views the following code defines a connection with the Microsoft Text Driver Chapter 11ConnectionString - Stored Procedures and and the12 source directory c:\: Chapter - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

Dim connectionString As Web String = _ using ASP.NET Chapter 14 - Developing Database Applications "Driver={Microsoft (*.txt; *.csv)};DBQ=c:\\" Chapter 15 - Using ADO.NETText in Xml Driver Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Every.txt or .csv file in the C:\ directory will be treated as a database table, which you pass in your SQL string:


OdbcConnection conn = new OdbcConnection(ConnectionString); OdbcDataAdapter da = new OdbcDataAdapter Appendix A - Relational Databases: Some Basic Concepts ("Select * FROM Employees.txt", conn Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

To test this code, create a Windows application, drop a DataGrid control onto the form, and use the Index code in Listing 10-3 for the Form_Load event. List of Figures List of Tables

Listing 10-3: Accessing the TextDB.txt File

List of Listings

List of Sidebars

Private Sub Form1_Load(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles MyBase.Load ' Connection string for a Text File Dim connectionString As String = _ "Driver={Microsoft Text Driver (*.txt; *.csv)};DBQ=c:\\" ' Query the Employees.txt file as a table Dim conn As OdbcConnection = New OdbcConnection(connectionString) conn.Open() ' Create a data adapter and fill a DataSet Dim da As OdbcDataAdapter = New OdbcDataAdapter _ ("Select * FROM Employees.txt", conn)

Dim ds As DataSet = New DataSet() Applied ADO.NET: Building Data-Driven Solutions da.Fill(ds, "TextDB") ISBN:1590590732 by Mahesh Chand Talbot ' Bind the DataSet toand a David DataGrid Apress © 2003 (928 pages) DataGrid1.DataSource = ds.DefaultViewManager This text provides extensive coverage of ADO.NET technology ' Close the connection including ADO.NET internals, namespaces, classes, and conn.Close() interfaces, and takes a comprehensive look at XML conn.Dispose() namespaces and classes, and how to integrate both with End Sub ADO.NET. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Note Don't forget to add a reference to the Microsoft.Data.Odbc namespace. Introduction

If you compile and run the application, you should see data in the DataGrid control. Chapter 1 - ADO.NET Basics Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Building Data-Driven Solutions Accessing Applied ExcelADO.NET: Databases by Mahesh Chand and David Talbot

ISBN:1590590732

You'll now learn how to © connect Excel databases. If you don't have an Excel database, you can export Apress 2003 (928topages) data from your Northwind database to test this example. As you did in the previous section, export the This text provides extensive coverage of ADO.NET technology Employees table including from Microsoft Access by right-clicking the table and ADO.NET internals, namespaces, classes, and selecting the Export option. (You and takes a comprehensive look at XML can also choose interfaces, File Ø Export). namespaces and classes, and how to integrate both with When you export,ADO.NET. make sure you select the Microsoft Excel 97-2000 (*.xls) option in the Save as Type

drop-down list. For this example, save the file as Employees.xls. Table Now,ofif Contents you open Employees.xls, it looks like Figure 10-10. Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Figure 10-10: Employees.xls data view


Again, you can access the Excel database either by using an ODBC DSN or by passing the database name directly in the connection string. In this example, you're passing the database name directly:



Dim ConnectionString as string = "Driver={Microsoft Excel Driver (*.xls)};DBQ=c:\\Employees.xls"



Chapter After that, 18 -the Object-Relational code should beMapping familiarinto.NET you. It's the same steps as creating a DataAdapter, selecting

some fields of the table, filling a DataSetConsiderations from the DataAdapter, and binding data with the data-bound Chapter 19 - Mapped Objects: Performance and Data Binding controls. test this code, create a Windows Chapter 20To - COM Interoperability and ADO.NET application, add a DataGrid control and a ListBox control21 to the form, and import the Microsoft.Data.Odbc namespace. Listing 10-4 shows the full Chapter - Messaging source 22 code. Chapter - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Listing 10-4: AccessingEmployees.xls Using the ODBC Data Provider



private void Form1_Load(object sender, System.EventArgs e) Index { of Figures List // Connection string for ODBC Excel Driver string ConnectionString = List of Listings @"Driver={Microsoft Excel Driver (*.xls)};DBQ=c:\Employees.xls"; List of Sidebars OdbcConnection conn = new OdbcConnection(ConnectionString); List of Tables

// Tables in Excel can be thought of as sheets and are queried as shown string sql = "Select EmployeeID, FirstName, LastName FROM Employees"; conn.Open(); OdbcDataAdapter da = new OdbcDataAdapter(sql, conn); DataSet ds = new DataSet(); da.Fill(ds, "Employees"); dataGrid1.DataSource = ds.DefaultViewManager;

listBox1.DataSource = ds.DefaultViewManager; Applied ADO.NET: Building Data-Driven Solutions listBox1.DisplayMember = "Employees.FirstName"; ISBN:1590590732 by Mahesh Chand and David Talbot } Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML The output of Listing 10-4 looks like Figure 10-11. namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Figure 10-11: Output of Listing 10-4


Applied ADO.NET: Data-Driven Solutions Implementing Two .NETBuilding 1.1 Updates by Mahesh Chand and David Talbot

ISBN:1590590732

The following twoApress .NET ©version 1.1 updates affect the ODBC data provider: 2003 (928 pages) This text provides extensive coverage of ADO.NET technology

Require FullTrust including forADO.NET OleDb, ODBC, internals, and namespaces, OracleClient: classes, Youand can now use portions of interfaces, andtrusted takes aapplications, comprehensive look XMLClient. This means that it's now System.Data in partially such asatSQL and classes, and how to integrate both with necessary tonamespaces require FullTrust permission for OleDb, ODBC, and OracleClient. It's not possible to ADO.NET. allow these providers to work in partially trusted scenarios because of their interaction with native pointers and Application Programming Interfaces (APIs). Table of Contents Applied ADO.NET—Building Data-Driven Solutions Workaround: If you're using .NET Framework version 1.0 and are setting system.data.dll as Introduction allowed in partially trusted scenarios, you must modify your security settings to allow these Chapter 1 - ADO.NET Basics components to work in partially trusted scenarios. Chapter 2 - Data Components in Visual Studio .NET Chapter 3


Removed an OnStateChange(Open) event from OLE DB client and ODBC client packages: The - ADO.NET in Connected Environments .NET Framework version 1.0 was incorrectly firing an OnStatechange(Open) event when there was Chapter 5 - Handling ADO.NET Events an invalid connection string. Chapter 4 Chapter 6


Chapter 7


Workaround: No workaround is available for this change. Generally, this indicates that the change Chapter 8 - Constraints and Data Relations isn't intended to have a workaround. Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Summary


ISBN:1590590732

The best thing about ADO.NET is pages) that it treats all types of data sources similarly. As we've stated Apress © 2003 (928 repeatedly, the only difference is the connection stringofand the class names. If you know how to build a This text provides extensive coverage ADO.NET technology connection string,including you canADO.NET use the same code to work with multiple data sources. Based on this theory, internals, namespaces, classes, and interfaces, and takes aOracle, comprehensive look at XML you saw how to work with the MySQL, and Sybase databases. You also saw how to work with namespaces and classes, and how to integrate both with Excel spreadsheets and text files. ADO.NET.

When it comes to the performance of database applications, server-side data objects such as stored procedures and views play a vital role. ADO.NET-with the help of VS .NET-provides great support for Table of Contents creating, managing, and executing stored procedures. The next chapter covers stored procedures and Applied ADO.NET—Building Data-Driven Solutions views, as well as how to write database applications using these two objects. Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 11: Stored Procedures ISBN:1590590732 and Views by Mahesh Chand and David Talbot Apress © 2003 Relational databases such as (928 SQLpages) Server and Oracle rely on stored procedures to do repetitive tasks, so This text provides extensive coverageapplications of ADO.NETare technology a programmer's main jobs when creating database creating, debugging, and testing including ADO.NET internals, namespaces, classes, and stored procedures (often called stored procs). Another database object it behooves programmers to learn interfaces, and takes a comprehensive look at XML is the view-or virtual table. In this you'll learn how to take of Visual Studio .NET (VS namespaces and chapter, classes, and how to integrate bothadvantage with .NET) tools to work with both stored procedures and views. ADO.NET.

Working with Stored Procedures

Table of Contents


User-defined stored procedures are handy for a variety of reasons. User-defined stored procs, as opposed to the built-in ones called system stored procedures, distribute load between a client and a database Chapter 1 - ADO.NET Basics on a database server but are executed by a client's call. Stored procedures not server because they reside Chapter 2 - Data Components Visual Studio .NETthey also provide better control, management, load only provide modularity in an in application design, Chapter 3 - ADO.NET in Disconnected distribution, and performance. In the Environments following sections, we discuss how to create and execute stored Chapter 4 - ADO.NET Connected Environments procedures using VS in .NET. Introduction

Chapter 5


Chapter 6

- Integrating XML with ADO.NET Creating a Stored Procedure

Chapter 7


Chapter 8 a - Constraints and to Data Relations You have variety of ways create stored procedures. As a database administrator, you can use the Chapter 9 server's - ADO.NET Exception Handling database administrative tools (SQL Server Enterprise Manager or Oracle Enterprise Manager, for Chapter example) 10 to - Working create and withmanage the ODBC stored .NET procedures. Data ProviderAs a programmer, you can create stored procedures

programmatically using theand CREATE Chapter 11 - Stored by Procedures Views PROCEDURE SQL statement. In this chapter, you'll learn how to create and stored procedures using VS Providers .NET. Chapter 12 - manage Oracle, SQLXML, and Other .NET Data Chapter 13 - Developing a Custom Data Provider

VS .NET's Server Explorer, discussed in Chapter 2, enables you to create, update, and delete You can launch the Server Explorer by selecting View Ø Server Explorer. After opening it, you'll see the available Chapter 15 - Using ADO.NET in Xml Web Services database servers in the list. If you expand a server tree node, you'll find the available databases and Chapter 16 - ASP.NET Server Controls and Data Binding database objects on the server. You can use the database's Stored Procedures node to managed stored Chapter 17 - Building Web Applications procedures. As you Real-World can see from Figure 11-1, the Stored Procedures node lists all the available stored Chapter 18 - Object-Relational in You .NETcan view stored procedures by double-clicking the stored procedures in the Northwind Mapping database. Chapter 19 - Mapped procedure's name. Objects: Performance Considerations and Data Binding Chapter 14 - Developing Database Web Applications using ASP.NET

Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 11-1: Viewing available stored procedures in the Northwind database The right-click menu option allows you to create a new stored procedure and edit, delete, and execute existing stored procedures (see Figure 11-2).


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4

- ADO.NET in Connected Environments Figure Create, edit,Events delete, and run stored procedure options Chapter 5 - 11-2: Handling ADO.NET Chapter 6


Chapter 7 Stored - Data Procedure Binding andoption Windows Data-Bound Controls The Edit letsForms you edit a stored procedure. To edit an existing stored procedure of Chapter the Northwind 8 - Constraints database, and right-click Data Relations the CustOrderHist stored procedure, and select the Edit Stored Chapter Procedure 9 - option. ADO.NET The Exception stored procedure Handling editor opens (see Figure 11-3). Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - 11-3: Building Real-World Web Applications Figure Stored procedure editor Chapter 18 - Object-Relational Mapping in .NET

Note SQL Server, thePerformance login that creates or has the ownership of a database or the administrator of Chapter 19 In - Mapped Objects: Considerations and Data Binding server is known asand the ADO.NET database owner. In the database and its objects, the username dbo is Chapter 20 the - COM Interoperability associated with the login name of the database owner. Chapter 21 always - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Now that you know how to edit an existing stored procedure, let's create a one. You can create a stored procedure by right-clicking the Stored Procedures node and selecting the New Stored Procedure option. Appendix B - Commonly Used SQL Statements This launches the stored procedure editor, which you use to write stored procedures. In SQL Server, dbo Appendix C -the ADO.NET Frequently Asked Questions stands for database owner. In Figure 11-4, the syntax CREATE PROCEDURE Index dbo.StoredProcedure2 creates a stored procedure where StoredProcedure1 is the name of the List of Figures stored procedure and dbo is the owner of the stored procedure. Appendix A - Relational Databases: Some Basic Concepts


Figure 11-4: Creating a stored procedure A stored procedure can return data as a result of SELECT statement, a return code (an integer value), or an output parameter. As you can see from Figure 11-4, the section after CREATE PROCEDURE is the parameters section, which is closed with comments (/* and */). If you have no requirement for using

parameters in a stored procedure, you can skip this area. The section after AS is used for the actual SQL Applied Building Data-Driven Solutions statement, and the sectionADO.NET: after RETURN is used for returning a value when you execute a stored ISBN:1590590732 by Mahesh Chand and David Talbot procedure. Apress © 2003 (928 pages)

Now, you can write a simple SELECT statement and save it as a stored procedure. Use this SQL This text provides extensive coverage of ADO.NET technology including ADO.NETvalues internals, classes, and statement to select three columns for namespaces, customers from the United States: interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with SELECT CustomerId, ADO.NET.CompanyName, ContactName

FROM Customers WHERE Country ='USA' Table of Contents Applied You can ADO.NET—Building change the stored Data-Driven procedureSolutions name to whatever you want; this example uses mySP (my stored Introduction procedure). The final stored procedure looks like Figure 11-5. Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


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Chapter 7


Chapter 8


Chapter 9



Figure 11-5: ThemySP stored procedure in the editor


Chapter 14save - Developing Applications You can a stored Database procedureWeb by using File Ø using SaveASP.NET mySP or the Save All menu option or toolbar Chapter 15 Using ADO.NET in Xml Web Services button. The Save option is also available after right-clicking on the stored procedure editor. Chapter 16 - ASP.NET Server Controls and Data Binding

Note Save Real-World option not only a stored procedure, but it also changes the CREATE Chapter 17 The - Building Web creates Applications statement to ALTER Chapter 18 PROCEDURE - Object-Relational Mapping in .NET PROCEDURE because the stored procedure has already been Chapter 19 created. - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Now, if you go to the Server Explorer and look at all the stored procedures for the Northwind database, your stored procedure should be listed. As you can see from Figure 11-6, the stored procedure mySP has Chapter 22 - SQL Server and ADO.NET: Notes on Performance three fields listed under it that appear in the SELECT statement. Chapter 21 - Messaging



ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Figure 11-6: ThemySP stored procedure listed for the Northwind database


Executing a Stored Procedure from VS .NET


Chapter 13 -a Developing a Custom DataServer Provider Executing stored procedure in the Explorer is simple. You run (or execute) a stored procedure by Chapter 14 Developing Database Web Applications using ASP.NET right-clicking on the stored procedure editor and selecting Run Stored Procedure. Chapter 15 - Using ADO.NET in Xml Web Services

When you the stored procedure mySP, theBinding output looks like Figure 11-7. Chapter 16 -run ASP.NET Server Controls and Data Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 11-7: The output of the mySP stored procedure in VS .NET Note Like your SELECT SQL statement, you can use almost any SQL statement, such as UPDATE andDELETE, in the stored procedure. (Exceptions include CREATE TRIGGER,CREATE VIEW, CREATE DEFAULT,CREATE PROCEDURE, and CREATE RULE.) A stored procedure can also accept input parameters. For example, the CustOrdersDetail stored procedure takes a parameter value of OrderID. Based on the OrderID value, it returns ProductName and calculates Discount and ExtendedPrice (see Figure 11-8).


ISBN:1590590732


11-8: Stored procedure with input parameter Table Figure of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction When you run the stored procedure, it asks you for the value of the OrderID parameter, as shown in Chapter - ADO.NET Basics Figure 111-9. Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter Figure 12 - 11-9: Oracle,Registering SQLXML, and a stored Other procedure .NET Data Providers parameter Chapter 13 - Developing a Custom Data Provider

The output of the stored procedure CustOrdersDetail looks like Figure 11-10.

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index

Figure 11-10: The output of stored procedure CustOrdersDetail


List of Listings

Executing a Stored Procedure Programmatically

List of Sidebars

As an application developer, most of the time you'll be creating and testing stored procedures programmatically. You can execute a stored procedure programmatically using the Command object. Instead of passing a SQL statement, you pass the stored procedure name as the SQL statement to execute a stored procedure. As you saw in Chapter 4, each data provider provides a Command object to execute SQL statements. The Command classes for the OleDb, ODBC, and Sql data providers are OleDbCommand,OdbcCommand, and SqlCommand (respectively). Listing 11-1 shows how to use SqlCommand to execute a stored procedure programmatically against a SQL Server database. Listing 11-1: Executing the mySP Stored Procedure Using the Sql Data Provider Sub Main()

' Create a Connection Object Applied ADO.NET: Data-Driven Solutions Dim ConnectionString AsBuilding String = "Integrated Security=SSPI;" & _ by "Initial Mahesh Chand and David Talbot Catalog=Northwind;" & ISBN:1590590732 _ Apress © 2003 (928 pages) "Data Source=localhost;" This text provides extensive of ADO.NET technology Dim conn As SqlConnection = coverage New SqlConnection(ConnectionString) including ADO.NET internals, namespaces, classes, and ' Open the connection interfaces, and takes a comprehensive look at XML conn.Open() namespaces and classes, and how to integrate both with ' Create ADO.NET. a SqlCommand object and pass mySP as the ' SQL command and set CommandType property to ' CommandType.StoredProcedure Table of Contents Dim cmd As SqlCommand = New SqlCommand("mySP", conn) Appliedcmd.CommandType ADO.NET—Building Data-Driven Solutions = CommandType.StoredProcedure Introduction ' Call ExecuteReader of SqlCommand ChapterDim 1 -reader ADO.NET As Basics SqlDataReader = cmd.ExecuteReader() Chapter'2 Read - Data all Components data and in Visual display Studio on .NETthe console reader.Read() ChapterWhile 3 - ADO.NET in Disconnected Environments Chapter 4 Console.Write(reader(0).ToString()) - ADO.NET in Connected Environments Chapter 5 Console.Write(reader(1).ToString()) - Handling ADO.NET Events Chapter 6 Console.WriteLine(reader(2).ToString()) - Integrating XML with ADO.NET ChapterEnd 7 -While Data Binding and Windows Forms Data-Bound Controls Console.Read() Chapter 8 - Constraints and Data Relations ' Close reader and connection Chapter 9 - ADO.NET Exception Handling reader.Close() Chapter 10 - Working with the ODBC .NET Data Provider conn.Close() Chapter 11 - Stored Procedures and Views End Sub Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 -two Using ADO.NET in Xml Web Services There are steps involved in executing a stored procedure from your program. First, you set the Chapter Command 16 -object ASP.NET property ServerCommandText Controls and Data to the Binding stored procedure name; second, you set the

CommandType property to CommandType.StoredProcedure. Listing 11-1 executes the mySP stored Chapter 17 - Building Real-World Web Applications procedure created in theMapping previousinsection. To test code in Listing 11-1, create a console application Chapter 18 -you Object-Relational .NET and type 11-1Objects: on the Main method. Don't forget and to import the following two namespaces to the Chapter 19Listing - Mapped Performance Considerations Data Binding project 20 before using Sql data provider classes: Chapter - COM Interoperability and ADO.NET Chapter 21 - Messaging

Imports Chapter 22 -System.Data SQL Server and ADO.NET: Notes on Performance Imports Appendix A -System.Data.SqlClient Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Listing 11-1, creates a SqlCommand object by passing the stored procedure as the first parameter of the SqlCommand constructor and then sets the CommandType property List of Figures CommandType.StoredProcedure. The result of Listing 11-1 looks like Figure 11-11. Index

List of Tables


Figure 11-11: The output of stored procedure mySP A stored procedure can also accept input, output, or both types of parameters. Next, let's modify the mySP

stored procedure a little bit. This time give the user an option to select the customers based on their Applied ADO.NET: Building Data-Driven Solutions country. The modified stored procedure looks like Figure 11-12. by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732


Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Figure 11-12: A stored procedure with parameters Chapter 1 - ADO.NET Basics

As you 2can- Data see from Figure 11-12, theStudio stored.NET procedure selects customers based on the country entered Chapter Components in Visual

by the user. You can use the SqlParameter class to create a parameter. The SqlParameter class has - ADO.NET in Disconnected Environments properties such as Direction and Value. The Direction property defines whether the stored Chapter 4 - ADO.NET in Connected Environments procedure is an input, output, or both. It also defines whether it has a return value. The Chapter 5 - Handling ADO.NET Events ParameterDirection enumeration defines values of Direction (see Table 11-1). Chapter 3

Chapter 6


Chapter 7


Chapter 8


Table 11-1: The ParameterDirection Members

MEMBER Chapter 9 - ADO.NETDESCRIPTION Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

Input

Input parameter


InputOutput Chapter 12 - Oracle, SQLXML, Both input andand Other output .NETparameter Data Providers Chapter 13 - Developing a Custom Data Provider

Output

Output only


ReturnValue Returns value from the stored procedure Chapter 15 - Using ADO.NET in aXml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

TheValue property sets the value of the parameter. The following code adds a parameter with the value UK. After you execute the mySP stored procedure, it will return customers from the United Kingdom only:



'Set the SqlParameter Dim param As SqlParameter = New SqlParameter() Chapter 22 - SQL Server and ADO.NET: Notes on Performance param = cmd.Parameters.Add("@country", SqlDbType.VarChar, 50) Appendix A - Relational Databases: Some Basic Concepts param.Direction = ParameterDirection.Input Appendix B - Commonly Used SQL Statements param.Value = "UK" Chapter 21 - Messaging


List of updated Figures source code looks like Listing 11-2, and the output of Listing 11-2 looks like Figure 11-13. The Listing 11-2 creates SqlParameter as the country and sets its value to UK.ExecuteReader only List of Tables

returns rows where Country = "UK". List of Listings List of Sidebars

Figure 11-13: Output of Listing 11-2 Listing 11-2: Using Parameters in a Stored Procedure

' Create a Connection Object Applied ADO.NET: Data-Driven Solutions Dim ConnectionString AsBuilding String = "Integrated Security=SSPI;" & _ by "Initial Mahesh Chand and David Talbot Catalog=Northwind;" & ISBN:1590590732 _ Apress © 2003 (928 pages) "Data Source=localhost;" This text provides extensive of ADO.NET technology Dim conn As SqlConnection = coverage New SqlConnection(ConnectionString) including ADO.NET internals, namespaces, classes, and ' Open the connection interfaces, and takes a comprehensive look at XML conn.Open() namespaces and classes, and how to integrate both with ' Create ADO.NET. a SqlCommand object and pass mySP as the ' SQL command and set CommandType property to ' CommandType.StoredProcedure Table of Contents Dim cmd As SqlCommand = New SqlCommand("mySP", conn) Appliedcmd.CommandType ADO.NET—Building Data-Driven Solutions = CommandType.StoredProcedure Introduction Chapter'Set 1 - ADO.NET Basics the SqlParameter ChapterDim 2 -param Data Components As SqlParameter in Visual Studio = New .NET SqlParameter()

= cmd.Parameters.Add("@country", SqlDbType.VarChar, 50) Chapterparam 3 - ADO.NET in Disconnected Environments = ParameterDirection.Input Chapterparam.Direction 4 - ADO.NET in Connected Environments = "UK"Events Chapterparam.Value 5 - Handling ADO.NET ExecuteReader of SqlCommand Chapter'6 Call - Integrating XML with ADO.NET As and SqlDataReader cmd.ExecuteReader() ChapterDim 7 -reader Data Binding Windows Forms = Data-Bound Controls ' Read all data and display on the console - Constraints and Data Relations While reader.Read() Chapter 9 - ADO.NET Exception Handling Console.Write(reader(0).ToString()) Chapter 10 - Working with the ODBC .NET Data Provider Console.Write(reader(1).ToString()) Chapter 11 - Stored Procedures and Views Console.WriteLine(reader(2).ToString()) Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers End While ChapterConsole.Read() 13 - Developing a Custom Data Provider Chapter'14 - Developing Database Web Applications using ASP.NET Close reader and connection Chapterreader.Close() 15 - Using ADO.NET in Xml Web Services Chapterconn.Close() 16 - ASP.NET Server Controls and Data Binding Chapter 8

Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

To return from a stored procedure, the only thing you need to do is change the stored procedure, Chapter 20 a- value COM Interoperability and ADO.NET which will and return a value as a parameter and set the parameter's Direction property as Chapter 21 store - Messaging follows:22 - SQL Server and ADO.NET: Notes on Performance Chapter Appendix A - Relational Databases: Some Basic Concepts

' Create a SqlParameter Appendix B - Commonly Used SQL Statements Dim param As SqlParameter = Questions new SqlParameter() Appendix C - ADO.NET Frequently Asked param.Direction = ParameterDirection.ReturnValue Index List of Figures List of Tables

Also, store the command's execution results in a number variable like this:

List of Listings

List of Sidebars

param = cmd.Parameters.Add("@counter", SqlDbType.Int)

Applied Building Data-Driven Note SeeListing 11-3 ADO.NET: for the complete source code. Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

ListingApress 11-3: © AddCat1 Stored Procedure 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and CREATE PROCEDURE AddCat1 interfaces, and takes a comprehensive look at XML @CategoryName namespaces andnchar(15), classes, and how to integrate both with @Description char(16), ADO.NET.

@Identity int OUT AS Table of Contents INSERT INTO Categories (CategoryName, Description) Applied ADO.NET—Building Data-Driven Solutions VALUES(@CategoryName, @Description) IntroductionSET @Identity = @@Identity Chapter 1 RETURN - ADO.NET@@ROWCOUNT Basics Chapter 2


Chapter 3


Chapter 4

- ADO.NET in Connected Environments Now you'll an example of Events using ParameterDirection.Output. To test this source code, create a Chapter 5 -see Handling ADO.NET

console6 application andXML these namespace Chapter - Integrating with ADO.NET references: Chapter 7


Imports Chapter 8 -System.Data Constraints and Data Relations Imports Chapter 9 -System.Data.Common ADO.NET Exception Handling Imports Chapter 10 -System.Data.SqlClient Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other Data Providers Next, create a stored procedure called.NET AddCat1 that adds a row to the Categories table and returns the Chapter 13 Developing a Custom Data Provider row count. Listing 11-3 defines the stored procedure. Chapter 14 - Developing Database Web Applications using ASP.NET

Listing 15 11-4 showsADO.NET how to use output Everything is similar to the previous samples except that Chapter - Using in Xml Webparameters. Services you need use the parameter direction Parameter-Direction.Output. Chapter 16 to - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

Listing 11-4: Executing a Stored Procedure with Output Parameter



' Create a Connection Chapter 20 - COM InteroperabilityObject and ADO.NET As String = "Integrated Security=SSPI;" & _ ChapterDim 21 -ConnectionString Messaging "Initial Catalog=Northwind;" Chapter 22 - SQL Server and ADO.NET: Notes on Performance & _ "Data Source=localhost;" Dim conn As SqlConnection = New SqlConnection(ConnectionString) Appendix B - Commonly Used SQL Statements ' Open the connection Appendix C - ADO.NET Frequently Asked Questions conn.Open() Index Dim sql As String = _ List of Figures "SELECT CategoryID, CategoryName, Description FROM Categories" List of Tables Dim da As SqlDataAdapter = New SqlDataAdapter(sql, conn) List of Listings da.InsertCommand = New SqlCommand("AddCat1", conn) List of Sidebars da.InsertCommand.CommandType = CommandType.StoredProcedure ' Create a SqlParameter Dim param As SqlParameter = _ da.InsertCommand.Parameters.Add("@RowCount", SqlDbType.Int) param.Direction = ParameterDirection.ReturnValue da.InsertCommand.Parameters.Add _ ("@CategoryName", SqlDbType.NChar, 15, "CategoryName") da.InsertCommand.Parameters.Add _ ("@Description", SqlDbType.Char, 16, "Description") param = da.InsertCommand.Parameters.Add _ ("@Identity", SqlDbType.Int, 0, "CategoryID") param.Direction = ParameterDirection.Output Appendix A - Relational Databases: Some Basic Concepts

' Creat a DataSet and fill it ADO.NET: Data-Driven Solutions Dim ds AsApplied DataSet = NewBuilding DataSet() ISBN:1590590732 by Mahesh Chand and David Talbot da.Fill(ds, "Categories") Apress © 2003 (928 pages) ' Creat a DataRow and add it to the DataSet's DataTable ThisDataRow text provides coverage of ADO.NET technology Dim row As = extensive ds.Tables("Categories").NewRow() including ADO.NET internals, namespaces, classes, and row("CategoryName") = "Beverages" interfaces, and takes a comprehensive look at XML row("Description") "Chai" namespaces and= classes, and how to integrate both with ds.Tables("Categories").Rows.Add(row) ADO.NET. ' Save changes to the database da.Update(ds, "Categories") Table of' Contents Output AppliedConsole.WriteLine(da.InsertCommand.Parameters ADO.NET—Building Data-Driven Solutions _ Introduction ("@RowCount").Value.ToString()) Chapter 1

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AppliedSQL ADO.NET: Building Data-Driven Solutions Understanding Injection by Mahesh Chand and David Talbot

ISBN:1590590732

One of the dangers of writing Web applications is that eventually someone will try to hack your Apress © 2003 public (928 pages) application, especially if it contains sensitive financial information as credit card numbers or bank This text provides extensive coverage of ADO.NET such technology account details. For hackers, one way to try to get this information from including ADO.NET internals, namespaces, classes, and your application is SQL injection. interfaces, andtotakes a comprehensive at XML Its use isn't necessarily limited applications that use look stored procedures, but we're presenting it here namespaces and classes, to integrate both with because of the way that stored procs are and oftenhow used. ADO.NET.

Let's say that the first page in the application requires users to enter a username and password. Once the hacker has tried the usual combinations of manager,sa,admin, and so on (you already know not to use Table of Contents obvious usernames such as these, right?), he might try entering the following: Applied ADO.NET—Building Data-Driven Solutions Introduction

myusername; SELECT Chapter 1 - ADO.NET Basicsusername FROM users Chapter 2


Chapter 3


Chapter 4 - ADO.NET in Connected Environments If the contents of the username box are passed directly into a stored proc, then the stored proc runs as Chapter 5 Handling ADO.NET Events normal when executed, except that the semicolon acts as a statement terminator and the additional Chapter 6 statement - Integrating with ADO.NET on what the proc returns, our hacker could now have a complete SELECT alsoXML runs. Depending Chapter 7 Data Binding and Windows Data-Bound Controls list of valid user IDs for the application.Forms The same technique can be used for passwords, so the hacker Chapter 8 log - Constraints and Data as Relations can now into the application any valid user. Chapter 9 - ADO.NET Exception Handling

How do10you stop this? The obvious wayProvider to trap SQL injection is to scan every text input for a Chapter - Working with themost ODBC .NET Data

semicolon and then pass only the input before the semicolon to the stored proc. Alternatively, if you detect a semicolon, return some kind of error page to hackers that lets them know you're onto them. A more Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers complex method of blocking SQL injection is to run stored procs from a component, rather than calling Chapter 13 - Developing a Custom Data Provider them directly from an ASP.NET page. In this way, the raw output from the stored proc isn't returned to the Chapter 14 - Developing Database Web Applications using ASP.NET hacker's browser, and the hacker receives no clues about your database's structure or data. Chapter 11 - Stored Procedures and Views



Applied ADO.NET: Building Data-Driven Solutions Working with Views by Mahesh Chand and David Talbot

ISBN:1590590732

Aview is a virtual Apress table that represents © 2003 (928 pages)data from one or more database tables. A view can also be a partial table. YouThis can text select data a single table or based on the sort and filter criteria providesfrom extensive coverage of multiple ADO.NETtables technology (using WHERE andincluding GROUP ADO.NET BY clauses) and save data as a view. You can also set permissions on views. internals, namespaces, classes, and interfaces,an and takes a comprehensive look at XML share the same database. The For example, a manager, accountant, and a clerk of a company namespaces and how to both with manager can access all data and fromclasses, different tables of integrate the database. The accountant can access partial ADO.NET. data from multiple tables, and the clerk can access partial data from a single table. You can create three different views based on the user rights and let the user access these views based on their rights. Table of Contents

In brief, the views do the following:

Applied ADO.NET—Building Data-Driven Solutions Introduction Provide a security mechanism to hide certain parts of a database or database tables from certain Chapter 1 - ADO.NET Basics users Chapter 2

- Data Components in Visual Studio .NET Permit to access data in a Environments customized way so that different users can see the same data in Chapter 3 - users ADO.NET in Disconnected

different ways at in theConnected same time Chapter 4 - ADO.NET Environments Chapter 5


- Integrating Creating a ViewXML with ADO.NET

Chapter 6 Chapter 7


Like stored youData can Relations create and manage views from the Server Explorer. To create a view, Chapter 8 - procedures, Constraints and expand a database, right-click the Views leaf, and select the New View option. This action launches a Chapter 9 - ADO.NET Exception Handling wizard that helps you pick tables. Use the Add button adds tables to the view designer (see Figure 11-14). Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Figure 11-14: Adding tables to the view designer


Appendix C - ADO.NET Frequently Asked Questions Index For this example, add three tables to the designer: Customers, Orders, and Employees. Figure 11-15

shows a few columns selected from each table. List of Figures List of Tables List of Listings List of Sidebars


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Figure 11-15: Creating a view after selecting columns from three tables

Chapter 4 save - ADO.NET in Connected Environments You can a view by using the Save button, by using File Ø Save, or by right-clicking on the view and Chapter 5 Save - Handling ADO.NET selecting ViewName (seeEvents Figure 11-16). Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure Saving a view Chapter 18 - 11-16: Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter - COM Interoperability andCustEmpView ADO.NET For this20 example, save the view as and click OK (see Figure 11-17). Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings

Figure 11-17: Entering a name for the view

List of Sidebars

When you now see the Server Explorer views, you'll see CustEmpView listed (see Figure 11-18).


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Figure 11-18: Available views in the Server Explorer


Executing a View from VS .NET

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Provider To execute a view, right-click it inData the Server Explorer and select Retrieve Data from the View option. The Chapter 14 CustEmpView - Developing Database Web Applications output of looks like Figure 11-19. using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - 11-19: Relational Databases: Basic Concepts Figure Results of the Some CustEmpView view after executing it from the Server Explorer Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Retrieving Data from a View Programmatically

Index

List of Figures

In the same way that you execute a stored proc, the Command object executes a view. You can retrieve List of Tables data a view programmatically by replacing the view name with the table name in a SQL statement. List of from Listings Listing 11-5 shows you how to use the CustEmpView view in an application. As you can see, the code List of Sidebars uses the CustEmpView view as the table name in the SELECT statement: SELECT * FROM CustEmpView

Listing 11-5: Executing a View Programmatically Private Sub Form1_Load(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles MyBase.Load ' Create a Connection Object Dim ConnectionString As String = "Integrated Security=SSPI;" & _

"Initial Catalog=Northwind;" & _ ADO.NET: Building Data-Driven Solutions "DataApplied Source=localhost;" ISBN:1590590732 by Mahesh Chand and David TalbotSqlConnection(ConnectionString) Dim conn As SqlConnection = New Apress © 2003 (928 pages) Dim adapter As SqlDataAdapter = _ This text provides extensive*coverage of ADO.NET technology New SqlDataAdapter("SELECT FROM CustEmpView", conn) including ADO.NET internals, namespaces, classes, and Dim ds As DataSet = New DataSet("CustEmpView") interfaces, and takes a comprehensive look at XML adapter.Fill(ds, namespaces "CustEmpView") and classes, and how to integrate both with DataGrid1.DataSource = ds.DefaultViewManager ADO.NET. End Sub Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction To test this code, create a Windows application in VS .NET, add a DataGrid control to the form, and

write the in Listing 11-5 on the Form_Load event. Also, don't forget to import the Chapter 1 code - ADO.NET Basics System.Data.SqlClient namespace in the Chapter 2 - Data Components in Visual Studio .NETproject. Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


The output of Listing 11-5 looks like Figure 11-20.

Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Figure output the CustEmpView view from a program Chapter 17 - 11-20: BuildingThe Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Caution TheORDER BY,COMPUTE,COMPUTE BY, and INTO SQL keywords don't work with views.


Filling a DataSet from Multiple Views



If you want, you can fill a DataSet from multiple views. You just need to change the SQL statement you used in Listing 11-5. For example, say you want to fill a DataSet from the CustEmpView and Invoices Appendix B - Commonly Used SQL Statements views. Just replace the SQL statement in Listing 11-5 with the following: Appendix A - Relational Databases: Some Basic Concepts Appendix C - ADO.NET Frequently Asked Questions Index

Dim adapter As SqlDataAdapter = New SqlDataAdapter _ ("SELECT * FROM CustEmpView; SELECT * FROM Invoices", conn)



Summary


ISBN:1590590732

VS .NET providesApress plenty©of support to create and manage stored procedures and views. This chapter 2003 (928 pages) discussed how you can take advantage of the VS .NET to create, manage, and execute stored This text provides extensive coverage of tools ADO.NET technology procedures and views. You also learned how to work with stored procedures and views programmatically including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML as well. namespaces and classes, and how to integrate both with ADO.NET. In the next chapter, we'll discuss two new data providers—Oracle and XML .NET—and see how to use

these data providers to work with Oracle databases and XML data sources. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 12: Oracle, SQLXML, and Other .NET Data ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) Providers This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and In previous chapters, we discussed the Sql, OleDb, and ODBC data providers and how to use them work interfaces, and takes a comprehensive look at XML with various databases including SQL Server, Access, Excel, and MySQL. As mentioned, ADO.NET is namespaces and classes, and how to integrate both with flexible enough so anyone can develop their data provider and add it to the library as an add-on. ADO.NET.

In this chapter, you'll see some more data providers. Once you've come to grips with any one data provider, working with the rest of them is a piece of cake. All data providers implement a similar class Table of Contents hierarchy model with onlyData-Driven a few changes. Applied ADO.NET—Building Solutions Introduction - ADO.NET Basics Using Oracle .NET Data Providers

Chapter 1 Chapter 2

- Data Components in Visual Studio .NET Besides3 the OleDb and ODBC providers, you can use other data providers to access an Oracle database: Chapter - ADO.NET in Disconnected Environments Chapter 4


Microsoft has developed the Oracle .NET data provider (although some documentation refers to it as - Handling ADO.NET Events theOracle managed provider.

Chapter 5 Chapter 6


Chapter 7 - has Datadeveloped Binding andthe Windows Data-Bound Controls Oracle OracleForms data provider for .NET or ODP.NET. Chapter 8

- Constraints and Data Relations CoreLab Software Development has developed the OraDirect.NET data provider. Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

So, why there are so many approaches to access a database? Why can't they just provide a single

Chapter 11 That's - Stored Procedures and Views provider? the pity and beauty of software development. Users are never satisfied. No matter how Chapter 12 Oracle, SQLXML, and Other .NETfind Data Providers somewhere complaining about it. It may be a good a product you develop, you'll always somebody Chapter 13 - Developing a Custom Data Provider performance issue, it may lack features, or it may contain bugs. Chapter 14 - Developing Database Web Applications using ASP.NET

By having ODBC and OleDb Chapter 15 -the Using ADO.NET in Xmldata Webproviders, Services you can leverage the existing ODBC and OLE DB technologies satisfactory to Controls developers with Oracle database. However, data access using OLE Chapter 16 - ASP.NET Server and working Data Binding DB and17 ODBC isn't satisfactory to developers. Chapter - Building Real-World Web ApplicationsFor example, when you compare the performance of the OleDb data provider to the performance of the Sql provider.


Chapter 19 - Mapped Objects: Performance Considerations anddata Datasources Binding and isn't designed to work with a The OleDB data provider provides data access for generic Chapter 20 COM Interoperability and ADO.NET specific database. OLE DB is a COM library, so the OleDb data provider uses COM Interop services Chapter 21 to - Messaging internally provide connectivity with Oracle databases, which causes a performance hit for each use Chapter 22 SQL Server and ADO.NET: Notesand on Performance because of- moving between the managed unmanaged spaces. On the other hand, the Oracle data Appendix - Relational Databases: Someonly. BasicNot Concepts providerAworks with Oracle databases only that, the Oracle data provider skips COM Interop Appendix servicesBand - Commonly provides database Used SQL Statements connectivity by directly using the Oracle Call Interface (OCI) as provided

by Oracle software. Appendix C -client ADO.NET Frequently Asked Questions Index

Note A recent survey, published in an article on MSDN (www.microsoft.com/indonesia/msdn/ManProOracPerf.asp ), claims that the Oracle data provider List of Tables could be lot faster than the OleDb data provider. List of Figures

List of Listings

List of Sidebars Microsoft's Oracle data provider is free and is included as part of Visual Studio .NET (VS .NET) 2003. If

you're running VS .NET 1.0, you need to install it separately. You can download it from the Microsoft's download section (http://microsoft.com/downloads/). The ODP.NET provider from Oracle Corporation is also free. You can download it from Oracle's Web site at http://otn.oracle.com/tech/windows/odpnet/content.html. OraDirect.NET currently costs $99 and is available at www.crlab.com/products.html. Caution There may be some changes in these URLs. See the C# Corner (www.c-sharpcorner.com) Downloads section for the latest links. In this chapter, you'll use Microsoft's Oracle .NET data provider.

Adding a Reference to the Oracle .NETSolutions Data Provider Applied ADO.NET: Building Data-Driven by Mahesh Chand and David Talbot

ISBN:1590590732

The Oracle data provider's functionality resides in the System.Data.OracleClient.dll assembly. Apress © 2003 (928 pages) You can find this assembly in your installation folder's Bin folder. The default path of this assembly is This text provides extensive coverage of ADO.NET technology C:\Program Files\Microsoft .NET\OracleClient.NET\Bin. To add a reference to this including ADO.NET internals, namespaces, classes, and assembly, you can use the Add Reference dialog box of VS .NET, as shown in Figure 12-1. interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure a reference System.Data.OracleClient.dll Chapter 12 - 12-1: Oracle,Adding SQLXML, and Otherto.NET Data Providers Chapter 13 - Developing a Custom Data Provider

Note In Microsoft VS .NET 2003, the System.Data.OracleClient namespace is already available without adding a reference to the System.Data.OracleClient.dll.


Chapter - ASP.NETto Server Controls and Data Binding Adding16 a reference System.Data.OracleClient.dll adds the System.Data.OracleClient Chapter 17 Building Real-World Applications namespace to your project. To Web use the Oracle data provider classes, you must add the following line to Chapter 18 - Object-Relational Mapping in .NET your project: Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 -System.Data.OracleClient COM Interoperability and ADO.NET Imports Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Using the Oracle .NET Data Provider Classes


Index The Oracle data provider class hierarchy model is similar to other data providers. As with other data List of Figures providers, it also has classes for Connection,Command,DataAdapter,DataReader,Transaction, List Parameter, of Tables and so on. Table 12-1 describes the Oracle data provider common classes briefly. List of Listings List Table of Sidebars 12-1: Oracle Data Provider Classes

CLASS

DESCRIPTION Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Connection class Apress © 2003 (928 pages)

OracleConnection

ISBN:1590590732

OracleCommand Command class This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

OracleCommandBuilder CommandBuilder interfaces, and takes a comprehensive look atclass XML

namespaces and classes, and how to integrate both with

OracleDataAdapter ADO.NET.

DataAdapter class

OracleDataReader

DataReader class

Table of Contents OracleParameter

Parameter class


OracleParameterCollection Introduction

ParameterCollection class

Chapter 1 - ADO.NET Basics OracleTransaction

Transaction class

Chapter 2


OraclePermission Permission class Chapter 3 - ADO.NET in Disconnected Environments Chapter 4 - ADO.NET in Connected Environments OracleException Exception class Chapter 5 - Handling ADO.NET Events

OracleBFile RepresentsOracleBFile objects designed to work with - Integrating XML with ADO.NET the Oracle Binary File BFILE data type Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Chapter 6

Chapter 8 - Constraints and Data Relations OracleLob Represents a Large Object Binary (LOB) data type Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

Creating the Connection: Chapter 11 - Stored Procedures and The Views First

Step


The first step to access a database is to create a connection. The OracleConnection class of the Oracle data provider is responsible for opening and closing a connection with the database.



Chapter 15 - Using ADO.NET class in Xmlhas Web Services TheOracleConnection four properties: ConnectionString,DataSource, Chapter 16 ASP.NET Server Controls and Data Binding ServerVersion, and State. The ConnectionString represents a connection string, which can Chapter - Building Web Applications contain17 data source Real-World or server name, security type, user ID, and password. Like the other data provider Chapter connection 18 - classes, Object-Relational the OracleConnection Mapping in .NET provides Open,Close,BeginTransaction,

CreateCommand, Dispose methods. Chapter 19 - Mappedand Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

A typical connection string looks like the following:



"Data ASource=Oracle8i;Integrated Security=yes" Appendix - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

where Oracle8i is the default Oracle database server instance.

Index

List ofNote Figures The Oracle .NET data provider works for Oracle 8i and later versions of Oracle. List of Tables

The following is another version of connection string with the user ID systemand password manager for the database server instance MYDB:

List of Listings

List of Sidebars

"Data Source=MYDB;User ID=system;Password=manager;"

Listing 12-1 creates an OracleConnection, opens the connection, reads data, and closes the connection. Listing 12-1: Connecting to an Oracle Database Dim connectionString As String = _ "Data Source=MYDB;User ID=system;Password=manager;"

Dim conn As OracleConnection = _ Applied ADO.NET: Building Data-Driven Solutions New OracleConnection(connectionString) ISBN:1590590732 by Mahesh Chand and David Talbot Try Apress © 2003 (928 pages) If (conn.State = ConnectionState.Closed) Then This text provides extensive coverage of ADO.NET technology conn.Open() End If including ADO.NET internals, namespaces, classes, and

interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ' Do something here ADO.NET.

Catch exp As Exception Table of Contents MessageBox.Show(exp.Message) Applied ADO.NET—Building Data-Driven Solutions Finally Introduction Chapter 1 Chapter 2

If (conn.State = ConnectionState.Open) Then

- ADO.NET Basics conn.Close() - Data End Components If in Visual Studio .NET

Try Chapter End 3 - ADO.NET in Disconnected Environments Chapter 4


Chapter 5


Chapter 6


Note Remember that for the ODBC .NET data provider, Oracle 8i has different connection string than - Data Binding and Windows Forms Data-Bound Controls Oracle 9i. When you use the Oracle .NET data provider, the same connection string format Chapter 8 - Constraints and Data Relations works for all Oracle databases version 8i or later. Chapter 7 Chapter 9



Executing SQL Commands

Chapter 11 - Stored Procedures and Views Chapter 12 - manner Oracle, SQLXML, and data Otherproviders .NET Data Providers In a similar to the other (Sql, OleDb, and ODBC), the Oracle data provider's OracleCommand class represents a command object. The OracleCommand class provides the Chapter 13 - Developing a Custom Data Provider

functionality to executeDatabase SQL queries or indirectly (through a DataAdapter). Chapter 14 - Developing Web directly Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

TheCommandText,CommandType,Connection,DesignTimeVisible,Parameters, Transaction, and UpdatedRowSource are OracleCommand properties. The CommandText property Chapter 17 - Building Real-World Web Applications represents the SQL query or stored procedure to execute. The CommandType represents the type of Chapter 18 - Object-Relational Mapping in .NET command, which is of type System.Data.CommandType. The Connection property represents the Chapter 19 - associated Mapped Objects: Considerations and Data Binding connection with aPerformance command. By default OracleCommand isn't visible in the Toolbox, but if you Chapter 20 COM Interoperability and ADO.NET want to make it visible and want to use it at design-time, you can set the DesignTimeVisible property Chapter 21The - Messaging totrue. OracleTransaction represents an Oracle transaction, and the UpdatedRowState Chapter 22 - SQL Server and on should Performance property represents how theADO.NET: Update Notes method apply command results to the DataRow. Chapter 16 - ASP.NET Server Controls and Data Binding


TheOracleCommand methods Cancel,Clone,CreateParameter,ExecuteNonQuery, Appendix B - Commonly Used SQL include Statements ExecuteOracleNonQuery, ExecuteOracleScalar, ExecuteReader, and ExecuteScalar. Appendix C - ADO.NET Frequently Asked Questions Index

Apart from the ExecuteOracleNonQuery and ExecuteOracleScalar methods, other methods will look familiar to you.


List Now of let's Listings create a sample application. Create a Windows application, add a reference to the Oracle .NET

data List of provider, Sidebars and import the System.Data and System.Data.OracleClient namespaces. After that, add three buttons and a DataGrid control to the form, and name the buttons InsertCmdBtn, UpdateCmdBtn, and DeleteCmdBtn. Then, we recommend you download the source code and open the project in VS .NET. On the form's load event handler, you call the method FillDataGrid, which fills data from a database to the DataGrid control. Listing 12-2 shows the form's load event handler and the FillDataGrid method. Listing 12-2: FillDataGrid Method Private Sub Form1_Load(ByVal sender As System.Object, _

ByVal e As System.EventArgs) Handles MyBase.Load Applied ADO.NET: Building Data-Driven Solutions FillDataGrid() ISBN:1590590732 End Sub by Mahesh Chand and David Talbot Apress © 2003 (928 pages) ThisFillDataGrid() text provides extensive coverage of ADO.NET technology Public Sub including internals, namespaces, classes, and conn = New ADO.NET OracleConnection(connectionString) interfaces, and takes a comprehensive look at XML sql =namespaces "SELECT and * FROM classes,STDTABLE" and how to integrate both with Try ADO.NET. ' Open the connection If (conn.State = ConnectionState.Closed) Then Table of Contents conn.Open() Applied ADO.NET—Building End If Data-Driven Solutions Introduction ' Create a command with SELECT query Chapter 1 - ADO.NET Dim Basics cmd As OracleCommand = New OracleCommand(sql) Chapter 2 - Data cmd.Connection Components in Visual=Studio conn.NET ' Create a dataEnvironments adapter Chapter 3 - ADO.NET in Disconnected Chapter 4

- ADO.NET in Connected Environments Dim adapter As ADO.NET OracleDataAdapter = _ Chapter 5 - Handling Events Chapter 6

New OracleDataAdapter(cmd) - Integrating XML with ADO.NET

Chapter 7

builder1 As Forms OracleCommandBuilder = _ - Data Dim Binding and Windows Data-Bound Controls

Chapter 8


Chapter 9

-

Chapter 10 Chapter 11 Chapter 12 Chapter 13 -

New OracleCommandBuilder() ' Create and fill a DataSet ADO.NET Exception Handling Dim ds As DataSet = New DataSet() Working with the ODBC .NET Data Provider adapter.Fill(ds, "STDTABLE") Stored Procedures and Views ' Bind DataSet with DataGrid Oracle, SQLXML, and Other .NET Data Providers DataGrid1.DataSource = ds.Tables(0) Developing a Custom Provider ' Close the Data connection

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 -Catch Using ADO.NET Xml Web Services exp Asin Exception Chapter 16 - ASP.NET Server Controls and Data Binding MessageBox.Show(exp.Message) Chapter 17 -Finally Building Real-World Web Applications Chapter 18 - Object-Relational If (conn.State Mapping in = .NET ConnectionState.Open) Then

conn.Close() Chapter 19 - Mapped Objects: Performance Considerations and Data Binding If Chapter 20 - COM End Interoperability and ADO.NET Try Chapter 21 -End Messaging ChapterEnd 22 -Sub SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

In the FillDataGrid method, you create a connection and a DataAdapter, and then you call the Fill method of the DataAdapter to fill a DataSet with data from a database. You may also have List of Figures noticed that you're reading data from STDTABLE. You may want to change this table name to the table List Tables thatofyou want to access. If you want to use STDTABLE, create this table in an Oracle database with four List of Listings columns named as STDNAME, STDADDRESS, STDDOB, and STDSRN of type varchar,varchar, List of Sidebars datetime, and long, respectively. Index

The next step is to execute a SQL query using OracleCommand. The method ExecuteSqlQuery, shown in Listing 12-3, executes a SQL query. As you can see, the code opens a connection, creates an OracleCommand object, sets its connection, CommandText, and CommandType properties, and then calls ExecuteNonQuery method. Listing 12-3: ExecuteSqlQuery Method Public Sub ExecuteSqlQuery(ByVal sql As String) Try conn = New OracleConnection()

conn.ConnectionString = connectionString Applied ADO.NET: Building Data-Driven Solutions If (conn.State = ConnectionState.Closed) Then ISBN:1590590732 by Mahesh Chand and David Talbot conn.Open() Apress © 2003 (928 pages) End If This text extensive coverage ADO.NET technology Dim cmd As provides OracleCommand = New of OracleCommand() including ADO.NET internals, namespaces, classes, and cmd.Connection = conn interfaces, and takes a comprehensive look at XML cmd.CommandText sql and how to integrate both with namespaces and = classes, cmd.CommandType = CommandType.Text ADO.NET. cmd.ExecuteNonQuery() Table of Contents Catch exp As Exception Applied ADO.NET—Building Data-Driven Solutions MessageBox.Show(exp.Message) Introduction Finally Chapter 1 Chapter 2

-If ADO.NET Basics (conn.State = ConnectionState.Open) Then -conn.Close() Data Components in Visual Studio .NET

Chapter 3

If in Disconnected Environments -End ADO.NET

ChapterEnd 4 -Try ADO.NET in Connected Environments

End Sub Chapter 5 - Handling ADO.NET Events Chapter 6


Chapter 7


Chapter 8


Now let's write the code for InsertCmdBtn,UpdateCmdBtn, and DeleteCmdBtnand construct SQL - ADO.NET Exception Handling INSERT,UPDATE, and DELETE queues. Once the queries are constructed, you need to call Chapter 10 - Working with the ODBC .NET Data Provider ExecuteSqlQuery.Listing 12-4 shows the code for all three buttons. Chapter 9


Chapter - Oracle, SQLXML, and .NET UPDATE, Data Providers Listing12 12-4: Constructing SQLOther INSERT, and DELETE Queries Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Private Sub InsertCmdBtn_Click(ByVal sender As System.Object, _

Chapter Using ADO.NET in Xml Web Services ByVal15e -As System.EventArgs) Handles InsertCmdBtn.Click Chaptersql 16 -=ASP.NET Server Controls "INSERT INTO " and Data Binding Chaptersql 17 -+= Building Real-World Web Applications " STDTABLE(STDNAME, STDADDRESS, STDSRN) " Chaptersql 18 -+= Object-Relational Mapping in'Some .NET "VALUES('AName', Address', 3583)" ChapterExecuteSqlQuery(sql) 19 - Mapped Objects: Performance Considerations and Data Binding ChapterFillDataGrid() 20 - COM Interoperability and ADO.NET

End Sub Chapter 21 - Messaging Private UpdateCmdBtn_Click(ByVal sender As System.Object, _ Chapter 22 -Sub SQL Server and ADO.NET: Notes on Performance ByVal Ae -As System.EventArgs) Handles UpdateCmdBtn.Click Appendix Relational Databases: Some Basic Concepts sql "UPDATEUsed STDTABLE SET STDADDRESS = " & _ Appendix B -=Commonly SQL Statements "'New Address' WHERE STDNAME = 'AName' " Appendix C - ADO.NET Frequently Asked Questions ExecuteSqlQuery(sql) FillDataGrid() List of Figures End Sub List of Tables Private Sub DeleteCmdBtn_Click(ByVal sender As System.Object, _ List of Listings ByVal e As System.EventArgs) Handles DeleteCmdBtn.Click List of Sidebars sql = "DELETE STDTABLE WHERE STDNAME = 'AName' " ExecuteSqlQuery(sql) FillDataGrid() End Sub Index

Note You may also notice that you call the FillDataGrid method to update the DataGrid once a query is executed.

Reading Fast Data Using a DataReader

TheOracleDataReader class provides the DataReader functionality for Oracle data providers. Applied ADO.NET: Data-Driven Solutions Besides the methods to read genericBuilding data types, the OracleDataReader class also provides methods to ISBN:1590590732 by Mahesh Chand and David Talbot read Oracle-specific data types. You can use all the methods of format ReadXXX to read general data Apress © 2003 (928that pages) types, and you can use methods start with ReadOracleXXX to read Oracle-specific data types. This text provides extensive coverage of ADO.NET technology GetOracleDbFile,GetOracleDateTime, GetOracleString, and GetOracleNumber are some of including ADO.NET internals, namespaces, classes, and the Oraclespecific read methods. interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with TheOracleDataReader has six properties: Depth,FieldCount,HasRows,IsClosed,Item, and ADO.NET.

RecordsAffected. The Depth property returns the depth of a row in a loop. TheFieldCount property returns the number of columns in a row. The HasRows and IsClosed properties represent Table whether of Contents the reader has any rows and closed, respectively. The Item property returns the value in a native format,ADO.NET—Building and the RecordsAffected property returns the number of rows affected after the execution of a Applied Data-Driven Solutions SQL query. Introduction Chapter 1

- ADO.NET Basics

Chapter 3


Listing 12-5 reads data from STDTABLE and adds it to a ListBox control. To test this code, create a Chapter 2 - Data Components in Visual Studio .NET Windows application and add a ListBox control to the form. Chapter - ADO.NET in Data Connected Environments Listing412-5: Reading Using OracleDataReader Chapter 5


Chapter 6


Dim connectionString As String = _ - Data Binding and Windows Forms Data-Bound Controls "Data Source=MYDB;User ID=system;Password=manager;" Chapter 8 - Constraints and Data Relations Dim conn As OracleConnection = _ Chapter 9 -New ADO.NET Exception Handling OracleConnection(connectionString) Chapter 10 -Dim Working with ODBC .NET Data Provider sql Asthe String = "SELECT * FROM STDTABLE" Chapter 11 -Try Stored Procedures and Views Chapter 12 - Oracle, and Other=.NET Data Providers IfSQLXML, (conn.State ConnectionState.Closed) Then Chapter 13 - Developingconn.Open() a Custom Data Provider Chapter 14 - Developing End If Database Web Applications using ASP.NET cmd inAsXml OracleCommand = New OracleCommand(sql) Chapter 15 - UsingDim ADO.NET Web Services cmd.Connection = Data connBinding Chapter 16 - ASP.NET Server Controls and DimReal-World reader Web As Applications OracleDataReader = cmd.ExecuteReader() Chapter 17 - Building ListBox1.Items.Add("NAME ADDRESS ") Chapter 18 - Object-Relational Mapping in .NET While (reader.Read()) Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Dim str As String Chapter 20 - COM Interoperability and ADO.NET str = reader.GetString(0) Chapter 21 - Messaging Str += ", " Chapter 22 - SQL Server and ADO.NET: Notes on Performance str += reader.GetString(1) Appendix A - Relational Databases: Some Basic Concepts ' Read more fields depends on your table Appendix B - Commonly Used SQL Statements ' Do something here Appendix C - ADO.NET Frequently Asked Questions ListBox1.Items.Add(str) Index End While List of Figures reader.Close() List of Tables Catch exp As Exception List of Listings MessageBox.Show(exp.Message) List of Sidebars Finally If (conn.State = ConnectionState.Open) Then conn.Close() conn.Dispose() End If End Try Chapter 7

Listing 12-5 used the generic data methods, but the code in Listing 12-6 demonstrates using the Oraclespecific DataReader methods. As you can see, the code uses the GetOracleString, GetOracleNumber, and GetOracleDateTime methods to read data in Oracle data types.

Listing 12-6: Using the Oracle-Specific DataReader Methods


ISBN:1590590732

While (reader.Read()) Apress © 2003 (928 pages) Dim oraStr As OracleString This text provides extensive coverage of ADO.NET technology oraStr = reader.GetOracleString(0) including ADO.NET internals, namespaces, classes, and Dim str As String oraStr.ToString() interfaces,=and takes a comprehensive look at XML namespaces and classes, and how to integrate both with oraStr = reader.GetOracleString(1) ADO.NET. Dim oraDtTime As OracleDateTime = _ reader.GetOracleDateTime(2) Dim Table of oraNum Contents As OracleNumber = _ reader.GetOracleNumber(3) Applied ADO.NET—Building Data-Driven Solutions End While Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3

in Disconnected Environments Reading- ADO.NET and Writing Data Using a DataAdapter

Chapter 4


Chapter 5 - Handling ADO.NET Events TheOracleDataAdapter class represents the DataAdapter for the Oracle data provider. Like the Chapter 6 -provider's Integrating XML with ADO.NET other data DataAdapter classes, this class also defines the Fill and Update methods. The Chapter Fill method 7 - Data fillsBinding a DataSet and Windows from a data Forms source, Data-Bound and the Controls Update method saves the changes made to a

DataSet to the database. Chapter 8 -back Constraints and Data Relations Chapter 9


Listing 12-7 creates an OracleDataAdapter object from a command. After that, code fills a DataSet, adds a row by using the Update method, and displays the updated data in a DataGrid control. To test Chapter 11 - Stored Procedures and Views this code, create a Windows application, add a DataGrid control, and add this code on the form load or a Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers button click event handler. Chapter 10 - Working with the ODBC .NET Data Provider


Chapter - Developing Web Data Applications ASP.NET Listing14 12-7: ReadingDatabase and Writing Using using OracleDataAdapter Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Dim connectionString As String = _ "Data Source=MYDB;User ID=system;Password=manager;" Chapter 18 Dim - Object-Relational Mapping in .NET conn As OracleConnection = _ Chapter 19 New - Mapped Objects: Performance Considerations and Data Binding OracleConnection(connectionString) Chapter 20 Dim - COMsql Interoperability and As String = ADO.NET "SELECT * FROM STDTABLE" Chapter 21 Try - Messaging Chapter 22 - SQL'Server ADO.NET: Notes on Performance Openand the connection Appendix A - Relational If (conn.State Databases: Some = ConnectionState.Closed) Basic Concepts Then conn.Open() Appendix B - Commonly Used SQL Statements End Frequently If Appendix C - ADO.NET Asked Questions ' Create a command with SELECT query Index Dim cmd As OracleCommand = New OracleCommand(sql) List of Figures cmd.Connection = conn List of Tables ' Create a data adapter List of Listings Dim adapter As OracleDataAdapter = _ List of Sidebars New OracleDataAdapter(cmd) Dim builder1 As OracleCommandBuilder = _ New OracleCommandBuilder() builder1.DataAdapter = adapter ' Create and fill a DataSet Dim ds As DataSet = New DataSet() adapter.Fill(ds, "STDTABLE") Dim stdTable As DataTable = ds.Tables("STDTABLE") ' Add a row Dim row As DataRow = ds.Tables(0).NewRow() row(0) = "New Name" row(1) = "New Address" Chapter 17 - Building Real-World Web Applications

row(2) = DateTime.Today Applied ADO.NET: row(3) = "1234"Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot stdTable.Rows.Add(row) Apress © 2003 (928 pages) adapter.Update(ds, "STDTABLE") text provides extensive of ADO.NET technology 'This Bind DataSet with coverage DataGrid including ADO.NET internals, namespaces, classes, and DataGrid1.DataSource = ds.Tables(0) interfaces, and takes a comprehensive look at XML Catch exp As namespaces Exception and classes, and how to integrate both with MessageBox.Show(exp.Message) ADO.NET. Finally ' Close the connection Table of Contents If (conn.State = ConnectionState.Open) Then Applied ADO.NET—Building Data-Driven Solutions conn.Close() Introduction End If Chapter 1 -End ADO.NET Try Basics Chapter 2


Chapter 3


Chapter 4

- ADO.NET in Connected Environments Caution When itADO.NET comes toEvents performance, the DataReader should be your first choice over a Chapter 5 - Handling Chapter 6

DataSet XML when reading data from a database. Don't forget to close a DataReader when - Integrating with ADO.NET

Chapter 7

you're doneand accessing data. - Data Binding Windows Forms Data-Bound Controls

Chapter 8


Reading- ADO.NET BFILEsException and LOBs Handling

Chapter 9

Chapter 10Binary - Working the and ODBC .NET Object Data Provider Reading File with (BFILE) Large Binary (LOB) data types are two more tasks that Oracle Chapter 11 Stored Procedures and Views developers don't encounter with other databases. The Oracle .NET data provider handles both of these Chapter 12 -wisely Oracle,with SQLXML, andofOther .NET Data Providers data types the help the OracleBFile and OracleLob classes. Chapter 13 - Developing a Custom Data Provider

TheOracleLob class provides to three Oracle data types: Blob,Clob, and NClob. The Blob Chapter 14 - Developing Database access Web Applications using ASP.NET data type binary data up Web to 4GB in the form of an array of bytes. The Clob data type contains Chapter 15 contains - Using ADO.NET in Xml Services

character data up to 4GB in the form of a string. The NClob data type contains the character data based on the national character set of the server with up to 4GB. Chapter 17 - Building Real-World Web Applications Chapter 16 - ASP.NET Server Controls and Data Binding

Chapter 18 - Object-Relational Mapping in .NET TheGetOracleBFile method of OracleDataReader returns an OracleBFile object. This code Chapter 19 BFILE - Mapped Objects: Performance reads the data type from an OracleConsiderations database: and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

Dim bf As OracleBFile = reader.GetOracleBFile(1)


TheGetOracleLob of OracleDataReader returns an OracleLob object containing data. The Appendix B - Commonlymethod Used SQL Statements followingCcode uses the GetOracleLob method to read LOB data types: Appendix - ADO.NET Frequently Asked Questions Index List of Figures reader.Read() List Dim of Tables blb As OracleLob = reader.GetOracleLob(1)

Dim buffer() As Byte = New Byte(100) {} List of Listings buffer(0) List of Sidebars = 0xCC buffer(1) = 0xDD blb.Position = 0 Dim lob As OracleLob = CreateTempLob(cmd,blb.LobType) Dim actual As Long = blb.CopyTo(lob)

Note If you want to know more about BFILE, LOB, and other data types and related classes, see the documentation of the Oracle .NET data provider. We could easily write more pages discussing other classes of Oracle data provider, but luckily, the documentation that comes with the Oracle data provider is full of samples. You shouldn't have to go

anywhere else to find the solution for your problems.


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Data-Driven Using the SQLXML and Building SQL XML .NETSolutions Data Providers by Mahesh Chand and David Talbot

ISBN:1590590732

Chapter 6 discussed the©major XML .NET-related classes found in the System.Xml namespace to read Apress 2003 (928 pages) and write XML documents. We also discussed XML integration with ADO.NET. The .NET Framework This text provides extensive coverage of ADO.NET technology Library also provides an XML .NET data provider to work with SQL Server 2000 and XML documents. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML and classes, and how to both with The .NET supportnamespaces was introduced in the SQLXML 2.0integrate library, which includes two data providers that can ADO.NET. be used to read XML data and write XML from and into SQL Server 2000 databases. These two data providers are the following: Table of Contents

The SQLXMLOLEDB provider, which is an OLE DB data provider that exposes SQLXML 2.0

Applied ADO.NET—Building Solutions functionality through Data-Driven ADO Introduction

The managed Chapter 1 SQLXML - ADO.NET Basics classes (the SQL XML .NET data provider) expose SQLXML 2.0 functionality through ADO.NET Chapter 2 - Data Components in Visual Studio .NET Chapter 3


Note Currently, SQLXML 3.0 is available for download with Service Pack 1. This chapter uses - ADO.NET in Connected Environments SQLXML 3.0, which by default copies to the C:\\Program Files\SQLXML 3.0\Bin folder.

Chapter 4 Chapter 5


Chapter 6 - Integrating XML withonly ADO.NET In this chapter, we concentrate on the SQL XML .NET data provider. Chapter 7 - Data Binding and Windows Forms Data-Bound Controls

Note get the latest and downloads for SQLXML, visit http://msdn.microsoft.com/sqlxml/. Chapter 8 To - Constraints and updates Data Relations Chapter 9


The SXDP is an add-on; you can download and install it from Microsoft's site (http://msdn.microsoft.com/sqlxml/). Installing SXDP copies the Chapter 11 - Stored Procedures and Views Microsoft.Data.SqlXml.dll library, which you should add to an application before you start using it Chapter 12 - Oracle, and Other Providers in an application. InSQLXML, VS .NET, you can .NET add aData reference to SXDP by using the Add Reference menu option Chapter 13 - Developing a Custom and selecting the Browse button.Data The Provider default path of SXDP is the C:\\Program Files\SQLXML Chapter 14 -folder Developing Database Web Applications using ASP.NET 3.0\Bin (see Figure 12-2). Chapter 10 - Working with the ODBC .NET Data Provider

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings

12-2: Adding a reference to Microsoft.Data.SqlXml.dll List ofFigure Sidebars Adding a reference to this library adds the Microsoft.Data.SqlXml namespace to the project. Obviously you include this namespace in your application to access the classes provided by the SXDP: imports Microsoft.Data.SqlXml

Unlike other data providers, the SQLXMLDP model consists of only three classes: SqlXmlCommand, SqlXmlParameter, and SqlXmlAdapter.

Using the FOR XML Keyword

SQL Server 2000Applied providesADO.NET: a FOR XML keyword that you can use with the SELECTstatement to read data Building Data-Driven Solutions from a SQL Server to XML format. Using this statement, you can generate XML in four formats: RAW, ISBN:1590590732 by Mahesh Chand and David Talbot AUTO, NESTED,Apress and EXPLICIT. © 2003 (928 pages) This textlooks provides extensive coverage of ADO.NET technology The syntax of FOR XML like the following: including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML and classes, and how to integrate both with FOR XML mode namespaces [, XMLDATA] [, ELEMENTS][, BINARY BASE64] ADO.NET.

where mode specifies the XML mode. It can be RAW, AUTO, or EXPLICIT. XMLDATAspecifies that an XML-Data schema should be returned. If ELEMENTS is specified, it produces columns as subelements; Applied ADO.NET—Building Data-Driven Solutions otherwise columns are mapped as XML attributes. This option is available for AUTO mode only. The Introduction choice of which to use is yours, as both options produce valid XML; however, using subelements is more Chapter 1 - ADO.NET Basics like XML and may be especially useful if you need to share data across systems that may not have XML Chapter - Data Components in Visual .NET BASE64 option specifies that any binary data retuned by parsers2that understand attributes. TheStudio BINARY Chapter 3 will - ADO.NET in Disconnected Environments the query be in 64-bit encoded format.

Table of Contents

Chapter 4


The following examples use this syntax. Chapter 5 - Handling ADO.NET Events Chapter 6


Using7 the SqlXmlAdapter Object Chapter - Data Binding and Windows Forms Data-Bound Controls Chapter 8

- Constraints and Data Relations TheSqlXmlAdapter object represents a partial DataAdapter. We said partial because unlike other

Chapter 9 - ADO.NET Exception Handling data providers' DataAdapter object, it only provides two methods: Fill and Update. Chapter 10 - Working with the ODBC .NET Data Provider

You can a SqlXmlAdapter from an XML document with arguments of a connection string and Chapter 11create - Stored Procedures and Views command These are two of the SqlXmlAdapter constructor: Chapter 12 -type. Oracle, SQLXML, andoverloaded Other .NET forms Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET _ Dim adapter As New SqlXmlAdapter(commandText, Chapter SqlXmlCommandType, 15 - Using ADO.NET in connectionString) Xml Web Services

Dim adapter As Server New SqlXmlAdapter(commandStream, _ Chapter 16 - ASP.NET Controls and Data Binding SqlXmlCommandType, connectionString) Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

The connection string for a SqlXmlAdapter is a standard OleDb connection string; however, the provider must be SQLOLEDB, the SQL Server provider. You can also create a SqlXmlAdapter from a Chapter 21 - Messaging SqlXmlCommand: Chapter 20 - COM Interoperability and ADO.NET


Dim adapter As New SqlXmlAdapter(SqlXmlCommand)


Appendix C - ADO.NET Frequently Asked Questions Index You can also specify the command string and command type later using the CommandText and List of Figures CommandType properties. You can use the SchemaPath property to read an XML document. List of Tables List of Listings cmd.CommandText = "EmployeeElement" List of Sidebars cmd.CommandType = SqlXmlCommandType.XPath

cmd.SchemaPath = "xmlDoc.xml"

TheFill method takes a DataSet as an argument and fills it with the data specified in the SELECT command, and the Update method sends a DataSet to save the changes to a data source. Listing 12-8 uses a SqlXmlAdapter to fill a DataSet and view data in a DataGridcontrol. The code also uses the Update method to add a new row to the database. Listing 12-8: UsingSqlXmlAdapter

Private Sub FillDataBtn_Click(ByVal sender As System.Object, _ ADO.NET: Building Data-Driven Solutions ByVal e As Applied System.EventArgs) Handles FillDataBtn.Click ISBN:1590590732 by Mahesh Chand and David Talbot Dim connectionString As String = _ Apress © 2003 (928 pages) "provider=sqloledb;server=mcb;database=Northwind;uid=sa;password=;" ThisDataRow text provides extensive coverage of ADO.NET technology Dim row As including internals, namespaces, classes, and Dim adapter As ADO.NET SqlXmlAdapter interfaces, and takes a comprehensive look at XML Dim cmd As SqlXmlCommand New SqlXmlCommand(connectionString) namespaces and classes,=and how to integrate both with cmd.RootTag = "ROOT" ADO.NET. cmd.CommandText = "EmployeeElement" cmd.CommandType = SqlXmlCommandType.XPath Table ofcmd.SchemaPath Contents = "xmlDoc.xml" AppliedDim ADO.NET—Building Data-Driven ds As DataSet = NewSolutions DataSet() Introduction adapter = New SqlXmlAdapter(cmd) Chapteradapter.Fill(ds) 1 - ADO.NET Basics Chapterrow 2 -=Data ds.Tables(0).Rows(0) Components in Visual Studio .NET = "New FName" Chapterrow("FName") 3 - ADO.NET in Disconnected Environments "New LName" Chapterrow("LName") 4 - ADO.NET in = Connected Environments Chapteradapter.Update(ds) 5 - Handling ADO.NET Events = ds.Tables(0) ChapterDataGrid1.DataSource 6 - Integrating XML with ADO.NET End7 Sub Chapter - Data Binding and Windows Forms Data-Bound Controls Chapter 8


Chapter 9



Using the SqlXmlParameter Object



TheSqlXmlParameter represents parameter, which you can use in a SqlXmlCommand. The Chapter 13 - Developing a Custom DataaProvider

SqlXmlParameter object provides only two properties: Name and Value. The Name property represents the name of the parameter. The Value property represents the value of the parameter.


Chapter 16 - ASP.NET Server Controls Data Binding TheCreateParameter method of and the SqlXmlCommand object creates the parameter object. The Chapter 17 Building Real-World Web Applications following code creates a parameter: Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Dim param As SqlXmlParameter

Chapter COM Interoperability and ADO.NET param20= -cmd.CreateParameter() Chapter 21 - Messaging param.Name = "LastName" Chapter 22 - SQL Server and ADO.NET: Notes on Performance param.Value = "Fuller" Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index

Using the SqlXmlCommand Object

List of Figures

List ofSqlXmlCommand Tables The object represents the Command object of SXDP. It is usually used to execute SQL List statements. of ListingsThe SqlXmlCommand constructor takes a connection string as its argument: List of Sidebars

public SqlXmlCommand(string connectionString)

where connectionString is the ADO or OLEDB connection string identifying the server, database, and the login information. A typical connection string looks like following: Dim connectionString As String = "Provider=SQLOLEDB; Server=(local); " & _ "database=Northwind; user id=UserLogin; password=UserPassword"

Using the SqlXmlCommand Methods

TheExecuteNonQuery method executes SQL statements that don't return any values such as INSERT, Applied ADO.NET: Building Data-Driven Solutions UPDATE, and DELETE statements. You can also use this method to execute an updategram or a ISBN:1590590732 by Mahesh Chand and David Talbot DiffGram that updates records but returns nothing. A DiffGram is an XML format that identifies current Apress © 2003 (928 pages) and original versions of data elements. See Chapter 22 for more details.

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Note What are updategrams? Updategrams are a feature of SQL Server 2000 that allow SQL Server interfaces, and takes a comprehensive look at XML database updates toand beclasses, definedand in XML The both updategrams format contains the XML namespaces how format. to integrate with nodes for each column of a database table. ADO.NET.

You can use the ExecuteStream and ExecuteToStream methods to write to streams. The Table ExecuteStream of Contents method returns a new Stream object, and the ExecuteToStream method writes the Applied query results ADO.NET—Building to an existing Data-Driven stream. Solutions Introduction

TheExecuteXmlReader method executes a query and returns results in an XmlReader object.

Chapter 1

- ADO.NET Basics

Chapter 2 To - Data in Visual .NET you need to add a reference to the System.Xml Note useComponents System.Xml in yourStudio application, Chapter 3 namespace. - ADO.NET in Disconnected Environments Chapter 4

- ADO.NET in Connected Environments TheCreateParameter method creates a parameter for SXDP, which can be used by Chapter 5 - Handling ADO.NET Events

SqlXmlCommand. YouXML can with set values for the Name and Value parameters of this object. The Chapter 6 - Integrating ADO.NET ClearParameter method parameters associated Chapter 7 - Data Binding and removes Windows all Forms Data-Bound Controls with a Command object. Chapter 8


Using the SqlXmlCommand Properties - ADO.NET Exception Handling

Chapter 9

Chapter 10 - Working with the ODBC .NETmany Data properties, Provider TheSqlXmlCommand object supports which are defined in Table 12-2. Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Table 12-2: The SqlXmlCommand Properties Chapter 13 - Developing a Custom Data Provider

ClientSideXml When setWeb to True, conversion the rowset to XML occurs on the client Chapter 14 - Developing Database Applications using of ASP.NET instead of on the server. This is useful when you want to move the Chapter 15 - Using ADO.NET in Xml Web Services

performance load to the middle tier. This property also allows you to wrap the existing stored procedures with FOR XML to get XML output.


Chapter SchemaPath 18 - Object-Relational in .NET This isMapping the name of the mapping schema along with the directory path (for example, C:\x\y\MySchema.xml). ThisBinding property specifies a mapping Chapter 19 - Mapped Objects: Performance Considerations and Data

schema for queries. The path specified can be absolute or relative. If Chapter 20 - COM Interoperability andXPath ADO.NET Chapter 21 - Messaging the path specified is relative, the base path specified in BasePath resolves

path. If the path isn't specified, the relative path is relative Chapter 22 - SQL Server the and relative ADO.NET: Notes on base Performance to the current directory. Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used XslPath This SQL is theStatements name of the XSL file along with the directory path. The path Appendix C - ADO.NET Frequently Questions specifiedAsked can be absolute or relative. If the path specified is relative, the Index List of Figures List of Tables

BasePath

List of Listings

List of Sidebars

base path specified in BasePath resolves the relative path. If the base path isn't specified, the relative path is relative to the current directory. This is the base path (a directory path). The value of this property resolves relative paths specified for the XSL file (using the XslPathproperty), the mapping schema file (using the SchemaPathproperty), or an external schema reference in an XML template (specified using mapping-schema attribute).

OutputEncoding

This specifies the requested encoding for the stream returned by the command execution. Some commonly used encodings are UTF-8, ANSI, and Unicode. UTF-8 is the default encoding.

Namespaces

XPath queries can include namespaces. If the schema elements are namespace-qualified (use a target namespace), the XPath queries against the schema must specify the namespace. This member enables the execution of XPath queries that use namespaces.

RootTag

This providesBuilding the singleData-Driven root elementSolutions for the XML generated by the Applied ADO.NET: command A valid XML document requires a single root-level tag. ISBN:1590590732 by Mahesh Chand execution. and David Talbot If the command executed generates an XML fragment (without a single topApress © 2003 (928 pages) level element), you can optionally specify the root element for the returning

This text provides extensive coverage of ADO.NET technology XML. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML CommandText namespaces This isand theclasses, text of the to execute. andcommand how to integrate both with ADO.NET.

CommandStream

This is the command stream to execute. This property is useful if you want to execute a command from a file (for example, an XML template). When usingCommandStream, only Template,UpdateGram, and DiffGram Table of Contents CommandType values are supported Applied ADO.NET—Building Data-Driven Solutions Introduction CommandType

This identifies the type of command being executed. This property is of type

Chapter 1

- ADO.NET Basics SqlXmlCommandType.

Chapter 2


Chapter 3 - describes ADO.NET inthe Disconnected Environments property. Table 12-3 SqlXmlCommandType Chapter 4 - ADO.NET in Connected Environments Chapter 5 - Handling ADO.NET Events Table 12-3: The SqlXmlCommandType Members Chapter 6 - Integrating XML with ADO.NET

COMMANDTYPE

DESCRIPTION

Chapter 7


Chapter Sql 8

- Constraints and Dataan Relations Executes SQL command (for example, SELECT * FROM Employees - ADO.NET Exception FOR XMLHandling AUTO).

Chapter 9


XPath

Executes an XPath command (for example, Employees[@EmployeeID=1]).



Template Chapter 13 - DevelopingExecutes a Customan Data XML Provider template. Chapter 14 - Developing Database Web Applications using ASP.NET

UpdateGram

Executes an updategram.


DiffGram Executes a DiffGram. Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

TemplateFile

Executes a template file. This allows you to execute updategrams and

Chapter 18 - Object-Relational Mapping in .NET DiffGrams.

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 SqlXmlCommand - Messaging Seeing

in Action


Listing 12-9 uses different methods andBasic properties of SqlXmlCommand to execute SQL queries. Appendix A - Relational Databases: Some Concepts Appendix B - Commonly Used SQL Statements

Listing 12-9: UsingSqlXmlCommand to Execute Commands


Imports System List of Figures Imports List of TablesSystem.IO Imports System.Xml List of Listings Imports Microsoft.Data.SqlXml

List of Sidebars

Module Module1 Sub Main() ExecuteStreamMethod() ExecuteToStreamMethod() SqlParamExecuteMethod() ExecuteNonQueryMethod() End Sub Public Sub ExecuteStreamMethod() Dim connectionString As String = _

"provider=sqloledb;server=mcb;database=Northwind;uid=sa;password=;" Applied ADO.NET: Dim sql As String = _ Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot FROM Employees "SELECT FirstName, Title, Address WHERE " & _ Apress © 2003 (928 pages) "LastName = 'Fuller' FOR XML AUTO" ThisSqlXmlCommand text provides extensive coverage of ADO.NET technology Dim cmd As = New SqlXmlCommand(connectionString) including ADO.NET internals, namespaces, classes, and cmd.CommandText = sql interfaces, and takes a comprehensive look at XML Try namespaces and classes, and how to integrate both with Dim st ADO.NET. As Stream = cmd.ExecuteStream() Dim stReader As StreamReader = New StreamReader(st) Console.WriteLine(stReader.ReadToEnd()) Table of Contents Catch exp As Exception Applied ADO.NET—Building Data-Driven Solutions Console.WriteLine(exp.Message) Introduction End Try Chapter - ADO.NET Basics End1 Sub Chapter 2


Public Sub ExecuteToStreamMethod() Chapter 3 - ADO.NET in Disconnected Environments As String = _ ChapterDim 4 -connectionString ADO.NET in Connected Environments Chapter "provider=sqloledb;server=mcb;database=Northwind;uid=sa;password=;" 5 - Handling ADO.NET Events

As String = ADO.NET _ ChapterDim 6 -sql Integrating XML with Title, Address FROM Employees WHERE " & _ Chapter"SELECT 7 - Data FirstName, Binding and Windows Forms Data-Bound Controls "LastName = 'Fuller' FOR XML AUTO" - Constraints and Data Relations Dim cmd As SqlXmlCommand = New SqlXmlCommand(connectionString) Chapter 9 - ADO.NET Exception Handling cmd.CommandText = sql Chapter 10 - Working with the ODBC .NET Data Provider Try Chapter 11 - Stored Procedures and Views Dim memStream As MemoryStream = New MemoryStream() Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Dim stReader As StreamReader = New StreamReader(memStream) Chapter 13 - Developing a Custom Data Provider cmd.ExecuteToStream(memStream) Chapter 14 - Developing Database Web using ASP.NET memStream.Position = Applications 0 Chapter 15 Using ADO.NET in Xml Web Services Console.WriteLine(stReader.ReadToEnd()) ChapterCatch 16 - ASP.NET Server Controls and Data Binding exp As Exception Chapter 17 Building Real-World Web Applications Console.WriteLine(exp.Message) ChapterEnd 18 -Try Object-Relational Mapping in .NET End19Sub Chapter - Mapped Objects: Performance Considerations and Data Binding Chapter 8


Public Sub ExecuteNonQueryMethod() Chapter 21 - Messaging AsNotes String = _ ChapterDim 22 -connectionString SQL Server and ADO.NET: on Performance Appendix"provider=sqloledb;server=mcb;database=Northwind;uid=sa;password=;" A - Relational Databases: Some Basic Concepts

Dim sql As String = _ "DELETE Employees WHERE LastName = 'tel'" Appendix C - ADO.NET Frequently Asked Questions Dim cmd As SqlXmlCommand = New SqlXmlCommand(connectionString) Index cmd.CommandText = sql List of Figures Try List of Tables cmd.ExecuteNonQuery() List of Listings Catch exp As Exception List of Sidebars Console.WriteLine(exp.Message) End Try End Sub Appendix B - Commonly Used SQL Statements

Public Sub SqlParamExecuteMethod() Dim connectionString As String = _ "provider=sqloledb;server=mcb;database=Northwind;uid=sa;password=;" Dim sql As String = _ "SELECT FirstName, Title, Address FROM Employees " & _ "FOR XML AUTO" Dim cmd As SqlXmlCommand = New SqlXmlCommand(connectionString) cmd.CommandText = sql

Try Applied Building Data-Driven Solutions Dim param As ADO.NET: SqlXmlParameter ISBN:1590590732 by Mahesh Chand and David Talbot param = cmd.CreateParameter() Apress © 2003 (928 pages) param.Name = "LastName" This text=provides extensive coverage of ADO.NET technology param.Value "Fuller" including ADO.NET internals, namespaces, classes, and Dim st As Stream = cmd.ExecuteStream() interfaces, and takes a comprehensive look at XML Dim stReader As and StreamReader = toNew StreamReader(st) namespaces classes, and how integrate both with Console.WriteLine(stReader.ReadToEnd()) ADO.NET. Catch exp As Exception Console.WriteLine(exp.Message) Table ofEnd Contents Try Applied Data-Driven Solutions EndADO.NET—Building Sub Introduction End Module Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3

- ADO.NET in Disconnected Environments Caution You get in anConnected exceptionEnvironments if you don't use the FOR XML directive in a SQL query and then try to Chapter 4 - ADO.NET Chapter 5

use general SQLEvents queries. - Handling ADO.NET

Chapter 6


Chapter 7


Chapter 8


Chapter 9



AppliedDatabase ADO.NET: Building Using a MySQL andData-Driven the .NETSolutions Data Provider by Mahesh Chand and David Talbot

ISBN:1590590732

In Chapter 10, weApress discussed access MySQL databases using the ODBC .NET data provider, but © 2003how (928to pages) you can also access MySQL databases using differentofinterfaces. Three common interfaces to access This text provides extensive coverage ADO.NET technology MySQL databases are as follows: including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces andprovider classes, with and how to integrate both with driver Using the ODBC .NET data the help of the MyODBC ADO.NET.

Using MySQL native .NET providers Table of Contents Using the OLEDB.NET solution, the MyOLDDB provider Applied ADO.NET—Building Data-Driven Solutions

To see more details about these interfaces, samples, links, and other resources, visit Introduction www.mysql.com/articles/dotnet/. Chapter 1 - ADO.NET Basics Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Summary


ISBN:1590590732

In this chapter, you added more providers to your data provider list. You learned about various data Apress © 2003 (928data pages) providers to access Oracle databases. We discussed theADO.NET Oracle .NET data provider in detail and showed This text provides extensive coverage of technology you how you can including access Oracle databases. ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, howand to integrate both The SQLXML .NET data provider providesand a fast optimized waywith to communicate between SQL Server ADO.NET. and XML. In this chapter, you saw how to install and work with the XML .NET data provider.

In the next chapter, you'll put all the data provider–related pieces together and work with some data provider internals. You'll also learn how to build your own custom data provider.

Table of Contents


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 13: Developing a Custom Data Provider ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

Highlights This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

ADO.NET allowsinterfaces, developers and astakes mucha flexibility comprehensive in creating look custom at XML data providers as Microsoft had namespaces classes, how to In integrate both with developing the SqlClient and and OleDb data and providers. other words, you can create data providers for ADO.NET. virtually any source of data you can think of, from file formats to Web services. Think about some of the possibilities this presents. If you needed to create a database application that works on top of a number of different databases such as Microsoft SQL Server and IBM DB2, you could Applied ADO.NET—Building Data-Driven Solutions build a Web service that does the actual database access while your custom data provider provides the Introduction front end. Figure 13-1 shows such an application would work.

Table of Contents

Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8

- Constraints and Data Relations Figure A Web-service-based Chapter 9 - 13-1: ADO.NET Exception Handling data provider that accesses a Relational Database Management

System (RDBMS) Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

Using an architecture like the one shown in Figure 13-1, you can have focused teams develop compatibility to the Web service you've created for data access. Your data provider only needs to know Chapter 13 - Developing a Custom Data Provider how to access the Web service, and you can build your application using the same Application Chapter 14 - Developing Database Web Applications using ASP.NET Programming Interface (API) as you would for direct database calls. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


Chapter The advantage 16 - ASP.NET of building ServeraControls system and like Data this isBinding obvious-you can start building your application on top of the

ADO.NET while the data provider, Web service architecture, and individual database Chapter 17 -interfaces Building Real-World Web Applications compatibility gets worked out.Mapping This is more Chapter 18 - Object-Relational in .NETthan a little helpful if you're working on a large project requiring cross-database compatibility. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

This example highlights why the ability to write a custom data provider is truly beneficial; it's a way to provide standard access to a nonstandard source of data. In other words, this provides a way to normalize Chapter 22 - SQL Server and ADO.NET: Notes on Performance the way you work with data regardless of the source. Chapter 21 - Messaging


Appendix In this chapter B - Commonly you'll build Used a SQL data Statements provider that allows access to data in pipe-delimited format, and you'll

provide aC standard .NET API by Asked implementing the Microsoft interfaces to create a custom data provider. Appendix - ADO.NET Frequently Questions The pipe-delimited format is common, especially to Unix systems, as a way to move data between Index systems. Many large Enterprise Resource Planning (ERP) systems support the ability to export data in this List of Figures format. Another popular format you could build support for is the Comma Separated Values (CSV) format, List of Tables which is more popular on Windows systems. This chapter begins with an overview of the data provider List of Listings interfaces.

List of Sidebars

ADO.NET: Building Data-Driven Solutions Overview ofApplied the Data Provider Interfaces by Mahesh Chand and David Talbot

ISBN:1590590732

Figure 13-2 shows a custom provider's interfaces, grouped by function, and shows how they use Apress © 2003data (928 pages) each other. As you can see, the custom datacoverage providerofhas four objects: Connection,Command,Reader, This text provides extensive ADO.NET technology andAdapter. The following sections discuss these objects and how they work. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Figure 13-2: A custom data provider at a high level

Chapter 6

- Integrating XML with ADO.NET Understanding the Connection Object - Data Binding and Windows Forms Data-Bound Controls

Chapter 7

Chapter 8 - Constraints and Relations AConnection object is anData individual session with a source of data. If it's a database connection, it's likely Chapter 9 Transfer - ADO.NET Exception Handling an open Control Protocol/Internet Protocol (TCP/IP) channel back to the server on a particular Chapter 10has - Working with the ODBC Data Provider port that been authenticated as.NET having access to the database. If your data source is a file, it's likely a Chapter 11 -on Stored Procedures andread Views file handle the file that will be from. To fully understand how generic this interface is, take a look at Chapter the IDbConnection 12 - Oracle, SQLXML, interface's and properties Other .NET in Table Data Providers 13-1 and methods in Table 13-2. Chapter 13 - Developing a Custom Data Provider

Table 13-1: The Properties of the Chapter 14 - Developing Database WebIDbConnection Applications using Interface ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

PROPERTY

DESCRIPTION


ConnectionString Chapter 17 - Building Real-World This Web property Applications represents how the data provider can find its data case of a file-based source, this could be the path to the Chapter 18 - Object-Relational source. MappingIn in the .NET file. If it's a Web service, it could be aBinding Uniform Resource Indicator Chapter 19 - Mapped Objects: Performance Considerations and Data (URI). Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging ConnectionTimeout

This property represents the amount of time the object should try to

Chapter 22 - SQL Server and ADO.NET: Notes on Performance connect before giving up. Appendix A - Relational Databases: Some Basic Concepts

Database If connecting to a multiple data source such as an RDBMS, this is the Appendix B - Commonly Used SQL Statements

name of the database to which it's connected. If connecting to an Extensible Markup Language (XML) file, it could potentially represent a section of the document.

Appendix C - ADO.NET Frequently Asked Questions Index List of Figures ListState of Tables List of Listings

This property represents the current state of the connection such as Open or Closed.

List of Sidebars

Table 13-2: The Methods of the IDbConnection Interface

METHOD

DESCRIPTION Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Starts a transaction Apress © 2003 (928 pages)

BeginTransaction()

ISBN:1590590732

ChangeDatabase() This text provides Changes extensive fromcoverage one database of ADO.NET to another technology within the current connection including ADO.NET internals, namespaces, classes, and Closes the connection look at XML interfaces, and takes a comprehensive namespaces and classes, and how to integrate both with CreateCommand() Returns an uninitialized instance of a command that works with this ADO.NET.

Close()

connection Open() Table of Contents

Opens the connection


After reading through the methods and properties of this interface, it should be obvious that you can use - ADO.NET Basics theIDbConnection interface to manage a connection to virtually any type of resource imaginable.

Chapter 1 Chapter 2


Chapter 3


Understanding the Command - ADO.NET in Connected EnvironmentsObject

Chapter 4 Chapter 5

- Handling ADO.NET Events The second major component of an ADO.NET data provider is the Command object as represented by the

Chapter 6 - Integrating ADO.NET IDbCommand interface.XML Thiswith interface represents a single action taken on the data source. Chapter 7 - Data Binding and Windows Forms Data-Bound Controls

TheIDbCommand interface gets Relations data from a data source or performs alterations on the data source. Chapter 8 - Constraints and Data Everything aboutException the behavior of your Command object is up to you. This means that you can, if you Chapter 9 -else ADO.NET Handling want, define your own data your own dialect of SQL) that's optimized for dealing with Chapter 10 - Working with thequery ODBClanguage .NET Data(or Provider the specific type of Procedures data with which your provider is dealing. However, developers who use SQL should Chapter 11 - Stored and Views probably a SQL-like language. If you complete meta-language that requires interpretation, Chapter 12write - Oracle, SQLXML, and Other .NEThave Data aProviders

you can interpret the CommandText string to execute whatever commands you need on the data source. If, for example, you're creating a Command object around selecting and altering text files, you can use a Chapter 14 - Developing Database Web Applications using ASP.NET regular expression and execute it against the text file and then return the results in a custom Chapter 15 - Using ADO.NET in Xml Web Services implementation of IDbDataReader.Table 13-3 describes the IDbCommand interface's properties, and Chapter 16 - ASP.NET Server Controls and Data Binding Table 13-4 describes its methods. Chapter 13 - Developing a Custom Data Provider


Table 13-3: The Properties of the IDbCommand Interface


PROPERTY DESCRIPTION Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

This property is a string that tells your Command object what to do. This can be SQL executed against the database, an XPATH query to choose Appendix A - Relational Databases: Some Basic Concepts a node in an XML document, or some other type of command that lets Appendix B - Commonly Usedyour SQL command Statementsobject know what it's expected to do. CommandText



CommandTimeout Index List of Figures ListCommandType of Tables List of Listings List of Sidebars

This property represents the amount of time the command should wait before canceling its operation. This property represents the type of command this is, such as a stored procedure or a text command.

Connection

This property represents the IDbConnection that this object uses.

Parameters

This property represents a collection of IDbParameter objects. If your command requires any type of information from the calling program to know what to do, the Parameters collection is the place to do it.

Transaction

This property represents the Transaction object that provides the context for a given transaction.

UpdatedRowSource

This property represents the row in the DataRow or DataTablethat's being altered.

Table 13-4: The Methods of the IDbCommand Interface


METHOD Cancel()

DESCRIPTION by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

Stops the current command

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and CreateParameter() Creates a new parameter in the Parameters collection interfaces, and takes a comprehensive look at XML namespacesExecutes and classes, how to integrate both with for a result set to be ExecuteNonQuery() theand command with no expectation ADO.NET. returned

ExecuteReader() Table of Contents

Returns an IDbDataReader object to iterate through the results of a query


ExecuteScalar()

Introduction

Returns a single object from the execution of the command

Chapter 1 - ADO.NET Basics Compiles or prepares the statement for execution if necessary Prepare() Chapter 2 - Data Components in Visual Studio .NET Chapter 3


Chapter 4

- ADO.NET in Connected Environments Understanding the Reader Object - Handling ADO.NET Events

Chapter 5

Chapter 6 - Integrating with ADO.NET TheReader object is aXML class that implements a number of interfaces; two interfaces are mandatory, and Chapter 7 Data Binding and Windows Forms Data-Bound one interface is optional. The two required interfaces areControls IDataReader and IDataRecord, which Chapter provide8the- structure Constraints forand iterating Data Relations through any forward-only data collection. IDataReader allows for the

iteration9 from one rowException to the next within your data source, and the IDataRecord object allows access to Chapter - ADO.NET Handling an individual row in the set. .NET Data Provider Chapter 10 - Working withresult the ODBC Chapter 11 - Stored Procedures and Views

The optional interface to implement is the IEnumerable interface. If you choose to implement this interface, you can bind your IDataReader object directly to ASP.NET and Windows Forms controls. In Chapter 13 - Developing a Custom Data Provider practice, there really isn't any reason why you shouldn't implement this interface because you only have to Chapter 14 - Developing Database Web Applications using ASP.NET implement one method that returns an instance of a DbEnumerator object. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


Chapter As mentioned, 16 - ASP.NET to create Server a working Controlsdata and provider, Data Binding you have to implement the IDataReader and

IDataRecord interfaces. A little later in this chapter you'll see an example implementation of these Chapter 17 - Building Real-World Web Applications methods together to Mapping provide ainmeans Chapter 18coming - Object-Relational .NET of reading a pipe-delimited file. The DbEnumerator object already19 knows how Objects: to manipulate these interfaces and translate into the behavior expected from a Chapter - Mapped Performance Considerations and Data them Binding standard object. Think of implementing this interface as a no-pain, much-to-gain type of Chapter 20IEnumerable - COM Interoperability and ADO.NET implementation. Listing 13-1 shows the implementation for an enumerator. Table 13-5 describes the Chapter 21 - Messaging IDataReader interface's properties, and Table 13-6 describes its methods.


Table 13-5: The Properties of the IDataReader Interface


Appendix C - ADO.NET Frequently Asked Questions PROPERTY DESCRIPTION Index List of Figures

The level of nesting in the result sets

ListIsClosed of Tables

Returns true if the connection is closed

Depth

List of Listings

RecordsAffected

List of Sidebars

Returns the number of records affected

Table 13-6: The Methods of the IDataReader Interface METHOD

DESCRIPTION

Close()

Closes the result set

GetSchemaTable()

Returns a table with the schema of the result set

NextResult()

Advances to the next result

Read()

Reads a single record

Listing 13-1: The Implementation for an Enumerator


ISBN:1590590732

Public Function GetEnumerator() As IEnumerator Implements _ Apress © 2003 (928 pages) IEnumerable.GetEnumerator This text provides extensive coverage of ADO.NET technology Return New System.Data.Common.DbEnumerator(Me) including ADO.NET internals, namespaces, classes, and End Function interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Using Visual Basic .NET, you'll find that creating the Reader object includes far more typing than actually thinking through the problem because of the level of verboseness required to implement an interface. Applied ADO.NET—Building Data-Driven Solutions Because the IDataRecordinterface includes strongly typed methods to get a column's value, you have Introduction to create an implementation for each and every GetXXX method. Table 13-7 describes the Chapter 1 - ADO.NET Basics IDataRecord interface's properties, and Table 13-8 describes its methods.

Table of Contents

Chapter 2


Chapter 3 - ADO.NET in Disconnected Environments Interface Table 13-7: The Properties of the IDataRecord Chapter 4


PROPERTY DESCRIPTION Chapter 5 - Handling ADO.NET Events Chapter 6

- Integrating XML with ADO.NET FieldCount The number of columns in the current row

Chapter 7


Item8 - Constraints A collection objects that represents the current row Chapter and DataofRelations Chapter 9



Table 13-8: The Methods of and the Views IDataRecord Interface Chapter 11 - Stored Procedures Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers METHOD DESCRIPTION Chapter 13 - Developing a Custom Data Provider

GetBoolean() GetsWeb a Boolean valueusing for the specified column Chapter 14 - Developing Database Applications ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services GetByte()

Gets a byte value for the specified column


GetBytes() Gets anApplications array of bytes for the specified column Chapter 17 - Building Real-World Web Chapter 18 - Object-Relational Gets Mapping in .NET for the specified column GetChar() a character Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

GetChars() Gets anADO.NET array of characters for the specified column Chapter 20 - COM Interoperability and Chapter 21 - Messaging GetData()

Gets an IDataReader for the specified column, which is useful for

Chapter 22 - SQL Server and ADO.NET: Notes on of Performance nested structures data Appendix A - Relational Databases: Some Basic Concepts

GetDataTypeName()

Gets a string that represents the data type for the specified column


Appendix C - ADO.NET Frequently Asked Questionsobject for the specified column GetDateTime() Gets a DateTime Index

GetDecimal()

List of Figures

ListGetDouble() of Tables List of Listings

Gets a decimal for the specified column Gets a double for the specified column

GetFieldType()

Gets a Type object for the specified column

GetFloat()

Gets a Float object for the specified column

GetGuid()

Gets a globally unique identifier for the specified column

GetInt16()

Gets a 16-bit integer for the specified column

GetInt32()


GetInt64()


GetName()

Gets a text name for the specified column

GetOrdinal()

Gets the column number of the column of a specified name

List of Sidebars

GetString() Applied ADO.NET: Gets a string for the specified column Building Data-Driven Solutions ISBN:1590590732 and Davidfor Talbot GetValue() by Mahesh Chand Gets an object the specified column


GetValues() This text provides Gets an array ofcoverage objects for the specified column extensive of ADO.NET technology including ADO.NET internals, namespaces, classes, and

IsDBNull() interfaces, and Returns True if the current column is null takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Understanding the Adapter Object Table of Contents

TheAdapter object implements the IDbDataAdapter interface and inherits from the DbDataAdapter object. The purpose of this object is to glue together the four IDbCommand objects required to get and Introduction alter the database. It also defines how a DataSet should be filled and how to go about reflecting changes Chapter 1 - ADO.NET Basics made in the DataSet back to your custom data source. Table 13-9 describes the properties of the Chapter 2 - Data Components in Visual Studio .NET IDbDataAdapter interface. Please note that this interface does not contain any methods, just properties. Applied ADO.NET—Building Data-Driven Solutions

Chapter 3


Chapter 4

- ADO.NET in Connected Environments Table 13-9: The Properties of the IDbDataAdapter Interface

Chapter 5


PROPERTY DESCRIPTION Chapter 6 - Integrating XML with ADO.NET Chapter 7


Chapter 8


SelectCommand

TheIDbCommand that loads data from the data source

InsertCommand TheIDbCommand Chapter 9 - ADO.NET Exception Handling that inserts data into the data source Chapter 10 - Working with the ODBC .NET Data Provider

UpdateCommand

TheIDbCommand that updates data in the data source


DeleteCommand TheIDbCommand that deletes data from the data source Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

TheIDbDataAdapter interface simply defines the four IDbCommand objects and how they work with a DataSet. Depending on the requirements for your custom data provider, you can potentially set this in the Chapter 16 - ASP.NET Server Controls and Data Binding constructor for your Adapter object. Table 13-10 describes the IDbDataAdapter interface's properties, Chapter 17 - Building Real-World Web Applications andTable 13-11 describes its methods. Chapter 15 - Using ADO.NET in Xml Web Services


Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Table 13-10: The Properties of the IDbDataAdapter Object Chapter 20 - COM Interoperability and ADO.NET

PROPERTY Chapter 21 - Messaging

DESCRIPTION

Chapter 22 - SQL Server and ADO.NET: Notes on Performance DefaultTableSourceName

Provides the name of the table that this adapter will use to

Appendix A - Relational Databases: Some Basic Concepts manage its mappings Appendix B - Commonly Used SQL Statements

AcceptChangesDuringFill Appendix C - ADO.NET Frequently AskedDetermines Questions if AcceptChanges is called on a DataRow when Index ListContainer of Figures List of Tables List of Listings

it's added to the DataSet

Gets a reference to the IContainer for this adapter (primarily used in the visual builder)

ContinueUpdateOnError

Determines if the rest of a DataSet is updated when there's an error on a single row

MissingMappingAction

Determines what should be done if the adapter is unable to determine what action to execute

MissingSchemaAction

Determines what should be done if the DataSet's schema does not match the adapter's schema

Site

Returns the ISite of this component, which is similar to a namespace but is for the Internet. This is similar to an XML namespace.

TableMappings

A collection of mappings between the source table and this DataTable

List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions Mahesh Chand David Talbot Table 13-11: ThebyMethods of theand IDbDataAdapter Object ISBN:1590590732 Apress © 2003 (928 pages)

PROPERTY Fill()

DESCRIPTION This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Fills thelook DataSet interfaces, and takes a comprehensive at XML using the SelectCommand of namespaces and classes, and how to integrate both with this adapter ADO.NET.

FillSchema()

Creates a DataTable within a DataSet with the schema handled by this adapter

Table of Contents

GetFillParameters() Applied ADO.NET—Building Data-Driven Solutions Gets the parameters required for the Introduction Chapter 1

- ADO.NET Basics

SelectCommand to be properly called to fill up this data

Chapter Update() 2 - Data Components in Visual Studio .NET Calls the appropriate InsertCommand, Chapter 3

UpdateCommand, or DeleteCommand as required - ADO.NET in Disconnected Environments

Chapter 4

- ADO.NET in Connected Environmentsto update the data source to reflect the changes

Chapter 5


Chapter 6 - Integrating XML with ADO.NET CreateRowUpdatedEvent() Chapter 7 Chapter 8

made in the DataSet Fills in the values of the RowUpdatedEventArgs

- Data Binding and Windows Forms Data-Bound object withControls the proper values for this adapter - Constraints and Data Relations

Fills in the values of a RowUpdatingEventArgs object with the proper values for this adapter Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views CreateTableMappings() Creates an instance of the Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers DataTableMappingCollection object CreateRowUpdatingEvent() Chapter 9 - ADO.NET Exception Handling


OnFillError()

Creates a FillError event


Chapter OnRowUpdated() 15 - Using ADO.NET in Xml Web Services Creates a RowUpdated event Chapter 16 - ASP.NET Server Controls and Data Binding

OnRowUpdating()

Creates a RowUpdating event


ShouldSerializeTableMappings() Chapter 18 - Object-Relational Mapping in .NET

If this object is serialized, determines whether the

table mappings beBinding serialized with it Chapter 19 - Mapped Objects: Performance Considerations and Data Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

As you can see, the DbDataAdapter object contains quite a few methods (Table 13-11 doesn't list all the methods, such as those inherited from MarshalByRefObject and Component). The good news is that Appendix A - Relational Databases: Some Basic Concepts you'll only have to override a few of them to create your custom data provider. Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix B - Commonly Used SQL Statements

Appendix - ADO.NET Asked Questions NoteC Most of the Frequently methods you implement can throw a NotSupportedException if that particular Index property or method doesn't have any context with your particular data source. You'll see this List of Figures used in several places in the PipedDataProvider application in the next section of this chapter. List of Tables List of Listings List of Sidebars

Applied ADO.NET: Data-Driven Solutions Building a Custom DataBuilding Provider by Mahesh Chand and David Talbot

ISBN:1590590732

Now that you understand the data provider interfaces, you'll implement a custom data provider that has the ability Apress © 2003 (928 pages) to fill a DataSetThis fromtext data in piped format. (This dataofprovider be read only for the sake of brevity.) Figure 13provides extensive coverage ADO.NETwill technology 3 shows the PipedDataProvider that you'll create in the following sections. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4 - 13-3: ADO.NET in from Connected Environmentsin Notepad Figure Data pipeddata.txt Chapter 5


Chapter XML with ADO.NET As you 6can- Integrating see from Figure 13-3, a piped format file is basically a series of columns separated by the pipe symbol Chapter (|). There's 7 - no Data data Binding typing-or and Windows even theForms suggestion Data-Bound of dataControls typing-other than what can be guessed from the strings

between pipe. Forand thisData reason, the object you'll implement will only support string data and not attempt to Chapter 8 each - Constraints Relations make a9guess that the first column in the figure should be an integer. Chapter - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

Creating the PipedDataConnection Object



Because data provider you'reData creating needs to access a file system object, the connection implemented in Chapter 13 the - Developing a Custom Provider Listing 14 13-2 manages the file handle the file provided to the object. Chapter - Developing Database Web for Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Listing 13-2: The PipedDataConnection Object


Imports Chapter 18 -System Object-Relational Mapping in .NET Imports Chapter 19 -System.Data Mapped Objects: Performance Considerations and Data Binding Imports System.IO


Namespace AppliedADO.DataProvider


Public Class PipedDataConnection Implements System.Data.IDbConnection



Public FileName As String

List of Figures Friend file As System.IO.StreamReader List of Tables List of Listings List of Sidebars Public Sub New(ByVal fn As String)

Me.FileName = fn file = New StreamReader(New FileStream(Me.FileName, FileMode.Open)) _State = ConnectionState.Open 'The constructor for this connection opens a file handle End Sub Public Sub NotSupported() Throw New System.NotSupportedException() End Sub Public Function BeginTransaction(ByVal iso As IsolationLevel) _

As IDbTransaction Implements IDbConnection.BeginTransaction Applied ADO.NET: Building Data-Driven Solutions NotSupported() ISBN:1590590732 by MaheshNothing Chand and David Talbot Return Apress © 2003 (928 pages) End Function This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Public Function BeginTransaction() _ interfaces, and takes a comprehensive look at XML As IDbTransaction Implements namespaces and classes,IDbConnection.BeginTransaction and how to integrate both with NotSupported()'We are not supporting transactions ADO.NET.

Return Nothing End Function Table of Contents Public Sub ChangeDatabase(ByVal newDB As String) _ Applied ADO.NET—Building Data-Driven Solutions Implements IDbConnection.ChangeDatabase Introduction NotSupported()'We are not supporting the ability to change databases Chapter 1 -End ADO.NET Sub Basics Chapter 2


Chapter 3

CreateCommand() _ -Public ADO.NET Function in Disconnected Environments

As IDbCommand Implements IDbConnection.CreateCommand Chapter 4 - ADO.NET in Connected Environments Chapter 5

DimADO.NET idbCmdEvents As IDbCommand - Handling

Chapter 6

idbCmd NewADO.NET PipedDataCommand() - Integrating XML=with

idbCmd - Data Return Binding and Windows Forms Data-Bound Controls 'Creates the command object Chapter 8 - Constraints and Data Relations End Function Chapter 7 Chapter 9



Public Sub Close() Implements IDbConnection.Close file.Close() Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers _State = ConnectionState.Closed Chapter 13 -the Developing Custom Data 'Closes file ahandle and Provider sets the state to closed Chapter 14 -End Developing Database Web Applications using ASP.NET Sub Chapter 11 - Stored Procedures and Views

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 -Public ASP.NET Server Controls Implements and Data Binding Sub Open() IDbConnection.Open Chapter 17 - Building Real-World Web Applications _State = ConnectionState.Open Chapter 'Since 18 we're - Object-Relational opening Mapping the file in .NET handle in the constuctor, we're

'just19setting state here. Considerations and Data Binding Chapter - Mapped the Objects: Performance Chapter 20 -End COM Sub Interoperability and ADO.NET Chapter 21 - Messaging

_State ConnectionState Chapter 22 -Dim SQL Server andAs ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Public ReadOnly Property State() As ConnectionState _ Implements IDbConnection.State Appendix C - ADO.NET Frequently Asked Questions Get Index Return _State List of Figures End Get List of Tables End Property Appendix B - Commonly Used SQL Statements

List of Listings List of Sidebars Public Property ConnectionString() As String Implements _

IDbConnection.ConnectionString Get Return FileName End Get Set(ByVal Value As String) FileName = Value End Set End Property Private _ConnectionTimeout = 0 Public ReadOnly Property ConnectionTimeout() As Integer Implements _

IDbConnection.ConnectionTimeout Applied ADO.NET: Building Data-Driven Solutions Get ISBN:1590590732 by Mahesh Chand and David Talbot Return _ConnectionTimeout Apress © 2003 (928 pages) End Get This text provides extensive coverage of ADO.NET technology End Property including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Private _Database = ""and how to integrate both with namespaces and classes, Public ReadOnly Property Database() As String Implements _ ADO.NET.

IDbConnection.Database Get Table of Contents Return _Database Applied ADO.NET—Building Data-Driven Solutions End Get Introduction End Property ChapterEnd 1 -Class ADO.NET Basics Chapter End Namespace 2 - Data Components in Visual Studio .NET Chapter 3


Chapter 4


Chapter 5


In the case- of the PipedDataConnection object, the connection string is a complete path and filename of the Integrating XML with ADO.NET file in piped format. As soon as you create a new FileStream object, the file handle opens; so, in the constructor Chapter 7 - Data Binding and Windows Forms Data-Bound Controls for this object, you set the ConnectionState to Open. When the Close() method is called on the Chapter 8 - Constraints and Data Relations PipedDataConnection object, the FileStream closes and the handle to the file is released. Chapter 6

Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider In the course of implementing this object, you'll find there are several methods that have no relevance to this Chapter 11 type - Stored Procedures particular of data source.and For Views example, ChangeDatabase() is meaningless because you're not working with Chapter 12 - or Oracle, SQLXML, Othersource .NET Data a database any other typeand of data with Providers named subsections. To avoid complexity, you can skip

BeginTransaction(). With these Chapter 13 - Developing a Custom Data methods Provider you simply throw a NotSupportedException to let the data provider know that this particular method or property isn't supported. Chapter 14system - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

This may sound like it would cause this connection to create all kinds of problems, but in a practical application it doesn't. The portions of code in the PipedDataConnection object that throw the NotSupportedException Chapter 17 - Building Real-World Web Applications will be understood and suppressed by the container they run in, assuming of course that you don't try to directly Chapter 18 - Object-Relational Mapping in .NET call them from your code. Chapter 16 - ASP.NET Server Controls and Data Binding


Creating the PipedDataCommand Object



TheCommand object for the piped data provider is the PipedDataCommand object. This object represents a

Appendix A - Relational Databases: Some Basic in Concepts single action taken against the data source; this case, the PipedDataCommand object can only load the entire Appendix Commonly UsedinSQL contentsBof- the file named the Statements PipedDataConnection object, so it has no need to actually interpret the Appendix C - ADO.NET Frequently Asked Questions CommandText property. Index

When this object is created, it's passed a string for the CommandText of the command and the List of Figures PipedDataConnection on which this command will take place. List of Tables List of Listings

The primary workhorse of this object is the ExecuteReader method. According to the interface it implements, the IDbCommand interface, this method should return something of the type IDataReader. In this case, a PipedDataReader is returned (PipedDataReader is defined in the next section of this chapter). Listing 13-3 shows the PipedDataCommand object.

List of Sidebars

Listing 13-3: The PipedDataCommand Object Imports System Imports System.Data Namespace AppliedADO.DataProvider Public Class PipedDataCommand

Implements System.Data.IDbCommand Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Public Sub New()

ISBN:1590590732

Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology End Sub including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Public Sub New(ByVal As String, pdc As PipedDataConnection) namespaces and classes,cmd and how to integrateByRef both with _CommandText = cmd ADO.NET.

_Connection = pdc End Sub Table of Contents Applied ADO.NET—Building Solutions Public Sub Data-Driven NotSupported() Introduction

Throw New NotSupportedException()

Chapter 1

-End ADO.NET Sub Basics

Chapter 2


Chapter 3

NotImpl() -Public ADO.NET Sub in Disconnected Environments

Chapter 4

Throw New NotImplementedException() - ADO.NET in Connected Environments

Chapter 5

SubADO.NET Events -End Handling

Chapter 6


Chapter 7

Suband Cancel() Implements IDbCommand.Cancel -Public Data Binding Windows Forms Data-Bound Controls

Chapter 8


Chapter 9


NotSupported() End Sub


Public Sub Prepare() Implements IDbCommand.Prepare End Sub



Chapter 13 -Public Developing a Custom Data Provider Function ExecuteNonQuery() _ Chapter 14 Developing Database Web Applications using ASP.NET As Integer Implements IDbCommand.ExecuteNonQuery Chapter 15 - UsingReturn ADO.NET0in Xml Web Services Chapter 16 -End ASP.NET Server Controls and Data Binding Function Chapter 17 - Building Real-World Web Applications Chapter 18 -Public Object-Relational Function Mapping CreateParameter()_ in .NET

As IDataParameter Implements IDbCommand.CreateParameter Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM NotSupported() Interoperability and ADO.NET

Return Nothing Chapter 21 - Messaging Function Chapter 22 -End SQL Server and ADO.NET: Notes on Performance ExecuteReader()_ Appendix A -Public RelationalFunction Databases: Some Basic Concepts As IDataReader Implements IDbCommand.ExecuteReader Dim reader As PipedDataReader Appendix C - ADO.NET Frequently Asked Questions reader = New PipedDataReader("ALL", _Connection) Index Return reader List of Figures End Function Appendix B - Commonly Used SQL Statements

List of Tables

List of Listings Public Function ExecuteReader(ByVal b As CommandBehavior) _ List Sidebars AsofIDataReader Implements IDbCommand.ExecuteReader

Return ExecuteReader() End Function Public Function ExecuteScalar() As Object Implements _ IDbCommand.ExecuteScalar NotImpl() Return Nothing End Function Private _CommandText As String

Public Property CommandText() As String Implements IDbCommand.CommandText Applied ADO.NET: Building Data-Driven Solutions Get ISBN:1590590732 by Mahesh Chand and David Talbot Return _CommandText Apress © 2003 (928 pages) End Get This text provides extensive coverage of ADO.NET technology Set(ByVal Value As String) including ADO.NET internals, namespaces, classes, and _CommandText = Value interfaces, and takes a comprehensive look at XML End Set and classes, and how to integrate both with namespaces End Property ADO.NET. Private _CommandTimeout = 0 Table of Contents Public Property CommandTimeout()_ Applied ADO.NET—Building Data-Driven Solutions As Integer Implements IDbCommand.CommandTimeout Introduction Chapter 1

Get

Chapter 2

- ADO.NET Basics Return _CommandTimeout - Data End Components Get in Visual Studio .NET

Chapter 3

Set(ByVal ValueEnvironments As Integer) - ADO.NET in Disconnected

Chapter 4

= Value - ADO.NET in_CommandTimeout Connected Environments

Chapter 5

EndADO.NET Set - Handling Events

Chapter 6

Property -End Integrating XML with ADO.NET

Chapter 7


Chapter 8


Chapter 9


Private _CommandType As CommandType

Public Property CommandType() As CommandType _ Implements IDbCommand.CommandType Chapter 11 - Stored Procedures and Views Get Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Return _CommandType Chapter 13 - Developing a Custom Data Provider End Get Chapter 14 - Developing Database Web Applications using ASP.NET Set(ByVal Value As CommandType) Chapter 15 - Using ADO.NET in Xml Web Services If (Value CommandType.Text) Then Chapter 16 - ASP.NET Server Controls and Data Binding NotSupported() Chapter 17 - Building Real-World Web Applications End If Chapter 18 - Object-Relational _CommandType Mapping in .NET = Value EndObjects: Set Performance Considerations and Data Binding Chapter 19 - Mapped Chapter 20 -End COM Property Interoperability and ADO.NET Chapter 10 - Working with the ODBC .NET Data Provider


As IDbConnection Chapter 22 -Private SQL Server_Connection and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Public Property Connection() As IDbConnection _ Implements IDbCommand.Connection Appendix C - ADO.NET Frequently Asked Questions Get Index Return _Connection List of Figures End Get List of Tables Set(ByVal Value As IDbConnection) List of Listings _Connection = Value List of Sidebars End Set End Property Appendix B - Commonly Used SQL Statements

Public ReadOnly Property Parameters() As _ IDataParameterCollection Implements IDbCommand.Parameters Get NotSupported() Return Nothing End Get End Property Public Property Transaction() As IDbTransaction _

Implements IDbCommand.Transaction Applied ADO.NET: Building Data-Driven Solutions Get ISBN:1590590732 by Mahesh Chand and David Talbot NotSupported() Apress © 2003 (928 pages) Return Nothing This text End Getprovides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Set(ByVal Value As IDbTransaction) interfaces, and takes a comprehensive look at XML NotSupported() namespaces and classes, and how to integrate both with End Set ADO.NET. End Property Public Property UpdatedRowSource() As UpdateRowSource _ Table of Contents Implements IDbCommand.UpdatedRowSource Applied ADO.NET—Building Data-Driven Solutions Get Introduction Return UpdatedRowSource.None Chapter 1 - ADO.NET End Basics Get Chapter 2 - Data Set(ByVal Components inValue Visual Studio As UpdateRowSource) .NET Chapter 3


Chapter 4

End inSet - ADO.NET Connected Environments

Chapter 5

Property -End Handling ADO.NET Events

ChapterEnd 6 -Class Integrating XML with ADO.NET

End Namespace Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Chapter 8


Chapter 9



Creating the PipedDataReader Object



For the13 calling programa to loop through and access the data in the piped data file, you have to implement a Chapter - Developing Custom Data Provider Reader object. The PipedDataReader object's responsibility is iterating through the data in the file and providing the data to the calling program in a strongly typed format. Chapter 15 - Using ADO.NET in Xml Web Services Chapter 14 - Developing Database Web Applications using ASP.NET

Chapter Controls and Data Binding Most of16 the- ASP.NET work thatServer this object does happens in the Read() method. This method reads the next line in the file Chapter 17 Building Real-World Web Applications and sets the internal object array _cols to the result. Once the _cols variable has been set, the different Chapter 18methods - Object-Relational Mapping in .NET to the calling program. GetXXX can provide this information Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

In the constructor for this object,and the ADO.NET Read() method is automatically called once and the connection is reset. The Chapter 20 - COM Interoperability reason21 for-this is so the object can "taste" the contents of the file and know how many columns to expect. Chapter Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

One of the traditional requirements of a file in piped format is that the column lengths be consistent. As an addition to the program in Listing 13-4, you could actually read through the whole file and verify that this is indeed the case Appendix - Commonly SQLaren't Statements and thenB throw an errorUsed if they the same length. Appendix A - Relational Databases: Some Basic Concepts Appendix C - ADO.NET Frequently Asked Questions

Listing 13-4: The PipedDataReader Object Index List of Figures List of TablesSystem Imports List of Listings Imports System.Data List of Sidebars Imports System.Data.Common

Imports System.IO Imports PipedDataProvider Namespace AppliedADO.DataProvider Public Class PipedDataReader Implements IDataReader, IDataRecord, IEnumerable Private _Command As String Public Sub New(ByVal cmd As String, ByRef conn As PipedDataConnection)

_Command = cmd Applied ADO.NET: Building Data-Driven Solutions _Connection = conn ISBN:1590590732 by Mahesh Chand and TalbotIn The Meta-Data 'Taste The File David To Fill Apress © 2003 (928 pages) Me.Read() This textTasted, provides extensive of ADO.NET technology 'File close coverage and reopen the connection including ADO.NET internals, namespaces, classes, and _Connection.Close() interfaces, and takes a comprehensive look at XML _Connection New and PipedDataConnection(_Connection.ConnectionString) namespaces and = classes, how to integrate both with End Sub ADO.NET. Private Sub NotSupported() Table of Contents Throw New NotSupportedException() Applied ADO.NET—Building Data-Driven Solutions End Sub Introduction Chapter 1

-Public ADO.NET Function Basics GetSchemaTable()_ Chapter As DataTable 2 - Data Components Implements in Visual IDataReader.GetSchemaTable Studio .NET Chapter 3

Me.NotSupported() - ADO.NET in Disconnected Environments

Chapter 4

Function -End ADO.NET in Connected Environments

Chapter 5

Close() -Public Handling Sub ADO.NET Events Implements IDataReader.Close

Chapter 6

_isClosed = ADO.NET True - Integrating XML with

Chapter 7

(Not Nothing) Then - Data If Binding and_Connection Windows Forms Is Data-Bound Controls

_Connection.Close() End If Chapter 9 - ADO.NET Exception Handling End Sub Chapter 8



Public Function NextResult() As Boolean Implements IDataReader.NextResult Return False Chapter 13 -End Developing a Custom Data Provider Function Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 -Private Using ADO.NET in Xml WebAs Services splitter() Char = {"|"} Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 -Public Building Real-World Applications FunctionWeb Read() As Boolean Implements IDataReader.Read Chapter 'This18is- Object-Relational the main method Mapping where in .NET a single line is read from the file and sets

'the value of the _cols collection. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding line As and String Chapter 20 - COM Dim Interoperability ADO.NET line = _Connection.file.ReadLine() Chapter 21 - Messaging If (line = "") Then Chapter 22 - SQL Server and ADO.NET: Notes on Performance Return False Appendix A - Relational Databases: Some Basic Concepts End If Dim tCols() As String Appendix C - ADO.NET Frequently Asked Questions tCols = line.Split(splitter) Index _cols = tCols List of Figures Return True List of Tables End Function Appendix B - Commonly Used SQL Statements

List of Listings List of Sidebars Private _depth = 3

Public ReadOnly Property Depth() As Integer Implements IDataReader.Depth Get Return _depth End Get End Property Private _isClosed = False Public ReadOnly Property IsClosed() As _ Boolean Implements IDataReader.IsClosed Get Return _isClosed

End Get Applied ADO.NET: Building Data-Driven Solutions End Property by Mahesh Chand and David Talbot Private _RecordsAffected As Integer ISBN:1590590732 Apress © 2003 (928 pages) Public ReadOnly Property RecordsAffected()_ This text provides extensive coverage of ADO.NET technology As Integer Implements IDataReader.RecordsAffected including ADO.NET internals, namespaces, classes, and Get interfaces, and takes a comprehensive look at XML Return namespaces and_RecordsAffected classes, and how to integrate both with End Get ADO.NET. End Property Table of Contents Public Function GetBoolean(ByVal i As Integer) _ Applied ADO.NET—Building Data-Driven Solutions As Boolean Implements IDataReader.GetBoolean Introduction

Return CType(_cols(i), Integer)

Chapter 1

-End ADO.NET Basics Function

Chapter 2


Chapter 3

GetByte(ByVal -Public ADO.NET Function in Disconnected Environments i As Integer) _

As Byte IDataReader.GetByte Chapter 4 -Implements ADO.NET in Connected Environments Chapter 5

Return CType(_cols(i), Byte) - Handling ADO.NET Events

Chapter 6

Function -End Integrating XML with ADO.NET

Chapter 7


Public Function GetBytes(ByVal i As Integer, ByVal _ - Constraints and Data Relations fieldoffset As Long, ByVal bytes()_ Chapter 9 - ADO.NET Exception Handling As Byte, ByVal length As Integer, ByVal bufferoffset As Integer) _ Chapter 10 - Working with the ODBC .NET Data Provider As Long Implements IDataReader.GetBytes Chapter 11 - Stored Procedures and Views NotSupported() Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Return Nothing Chapter 13 -End Developing a Custom Data Provider Function Chapter 8

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 -Public Using ADO.NET in Xml GetChar(ByVal Web Services Function i As Integer) _ Chapter 16 ASP.NET Server Controls and Data Binding As Char Implements IDataReader.GetChar Chapter 17 - Building Real-World Web Applications Char) Return CType(_cols(i), Chapter 18 -End Object-Relational Function Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Function and GetChars(ByVal i As Integer, ByVal fieldoffset As Long, _ Chapter 20 -Public COM Interoperability ADO.NET ByVal21buffer As Char(), ByVal length As Integer, ByVal bufferoffset As Integer) _ Chapter - Messaging As Long Chapter 22 -Implements SQL Server andIDataReader.GetChars ADO.NET: Notes on Performance NotSupported() Appendix A - Relational Databases: Some Basic Concepts Return Nothing End Function

Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index

Public Function GetData(ByVal i As Integer) As _ IDataReader Implements IDataReader.GetData List of Tables NotSupported() List of Listings Return Nothing List of Sidebars End Function Public Function GetDataTypeName(ByVal i As Integer) _ As String Implements IDataReader.GetDataTypeName Return GetType(String).ToString() End Function List of Figures

Public Function GetDateTime(ByVal i As Integer) _ As DateTime Implements IDataReader.GetDateTime Return CType(_cols(i), DateTime) End Function Public Function GetDecimal(ByVal i As Integer) As _

Decimal Implements IDataReader.GetDecimal Applied ADO.NET: Building Data-Driven Return CType(_cols(i), Decimal)Solutions ISBN:1590590732 by Mahesh Chand and David Talbot End Function Apress © 2003 (928 pages) ThisFunction text providesGetDouble(ByVal extensive coverage of iADO.NET technologyAs _ Public As Integer) including ADO.NET internals, namespaces, classes, and Double Implements IDataReader.GetDouble interfaces, and takes a comprehensive look at XML Return CType(_cols(i), Integer) namespaces and classes, and how to integrate both with End Function ADO.NET.

Public Function GetFieldType(ByVal i As Integer) As _ Table of Implements Contents Type IDataReader.GetFieldType Applied ADO.NET—Building Solutions Return Data-Driven GetType(String) Introduction End Function Chapter 1 - ADO.NET Basics Chapter 2

-Public Data Components Function in Visual GetFloat(ByVal Studio .NET i As Integer) As _ Single IDataReader.GetFloat Chapter 3 Implements - ADO.NET in Disconnected Environments Chapter 4

Return CType(_cols(i), - ADO.NET in Connected Environments Single)

Chapter 5

Function -End Handling ADO.NET Events

Chapter 6


Function GetString(ByVal As Integer) As _ -Public Data Binding and Windows Forms Data-BoundiControls String Implements IDataReader.GetString Chapter 8 - Constraints and Data Relations Return CType(_cols(i), String) Chapter 9 - ADO.NET Exception Handling End Function Chapter 7


Public Function GetGuid(ByVal i As Integer) As _ Guid Implements IDataReader.GetGuid Chapter 13 - Developing a Custom Data Provider Return CType(_cols(i), Guid) Chapter 14 -End Developing Database Web Applications using ASP.NET Function Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 -Public ASP.NET Server Controls and Data Binding i As Integer) As _ Function GetInt16(ByVal Chapter 17 Building Real-World Web Applications Short Implements IDataReader.GetInt16 Chapter 18 - Object-Relational Return CType(_cols(i), Mapping in .NET Short)

Function Chapter 19 -End Mapped Objects: Performance Considerations and Data Binding Function and GetInt32(ByVal i As Integer) As _ Chapter 20 -Public COM Interoperability ADO.NET Int3221Implements Chapter - Messaging IDataReader.GetInt32 Return Int32) Chapter 22 - SQL Server andCType(_cols(i), ADO.NET: Notes on Performance Function Appendix A -End Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Public Function GetInt64(ByVal i As Integer) As _ Int64 Implements IDataReader.GetInt64 Index Return CType(_cols(i), Int64) List of Figures End Function Appendix C - ADO.NET Frequently Asked Questions

List of Tables

List of Listings Public Function GetName(ByVal i As Integer) As _ List of Sidebars String Implements IDataReader.GetName

Return "COLUMN" + i.ToString() End Function Public Function GetOrdinal(ByVal name As String) As _ Integer Implements IDataReader.GetOrdinal NotSupported() Return Nothing End Function Public Function GetValue(ByVal i As Integer) As _ Object Implements IDataReader.GetValue

Return CType(_cols(i), Object) Applied ADO.NET: Building Data-Driven Solutions End Function ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) Public Function GetValues(ByVal values As Object()) As _ This text provides extensive coverage of ADO.NET technology Integer Implements IDataReader.GetValues including ADO.NET internals, namespaces, classes, and Dim i As Integer interfaces, and takes a comprehensive look at XML If (FieldCount < 1) namespaces and classes, andThen how to integrate both with Return 0 ADO.NET.

End If For i = 0 To FieldCount - 1 Table of Contents values(i) = _cols(i) Applied ADO.NET—Building Next Data-Driven Solutions Introduction Return FieldCount Chapter 1 -End ADO.NET Basics Function Chapter 2


Chapter 3

IsDBNull(ByVal i As Integer) As _ -Public ADO.NET Function in Disconnected Environments

Boolean Implements IDataReader.IsDBNull Chapter 4 - ADO.NET in Connected Environments Chapter 5

Return False - Handling ADO.NET Events

Chapter 6

Function -End Integrating XML with ADO.NET

ReadOnly Property FieldCount() -Public Data Binding and Windows Forms Data-Bound ControlsAs Integer _ Implements IDataReader.FieldCount Chapter 8 - Constraints and Data Relations Get Chapter 9 - ADO.NET Exception Handling Return _cols.Length - 1 Chapter 10 - Working with the ODBC .NET Data Provider End Get Chapter 11 - Stored Procedures and Views End Property Chapter 7


Chapter 13 -Default DevelopingPublic a CustomReadOnly Data Provider Property Item(ByVal name As String) _ Chapter 14 Developing Database Web Applications using ASP.NET As Object Implements IDataReader.Item Chapter 15 - UsingGet ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Me.NotSupported() Chapter 17 - Building Real-World Applications Return Web Nothing Chapter 18 - Object-Relational 'Return Mapping _cols(Array.IndexOf(_names, in .NET name))

EndObjects: Get Performance Considerations and Data Binding Chapter 19 - Mapped Chapter 20 -End COM Property Interoperability and ADO.NET Chapter 21 - Messaging

ReadOnly Property Item(ByVal i As Integer) _ Chapter 22 -Default SQL ServerPublic and ADO.NET: Notes on Performance As Object Implements IDataReader.Item Appendix A - Relational Databases: Some Basic Concepts Get


Return _cols(i) End Get End Property



Public Function GetEnumerator() As IEnumerator Implements _

List of Listings IEnumerable.GetEnumerator List of Sidebars

Return New System.Data.Common.DbEnumerator(Me) End Function Private _Connection As PipedDataConnection Private _cols() As Object

End Class End Namespace

There are portions of the object that Building are hard-coded such as the type of data supported. Because piped format Applied ADO.NET: Data-Driven Solutions contains no meta-data as to the data types of each column, you have to assume that they're all strings. Also, ISBN:1590590732 by Mahesh Chand and David Talbot because there's no meta-data, the columns are not actually named, so the PipedDataReader has to invent a Apress © 2003 (928 pages) column name for each column based on its position.

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and The final item of interest in the PipedDataReader object is the IEnumerableinterface and its related interfaces, and takes a comprehensive look at XML implementation. By implementing this interface, you yourboth PipedDataReader to be bound directly to Web namespaces and classes, and how to allow integrate with page and Windows ADO.NET. Forms controls. In situations where performance is an absolute requirement down to the last

processor cycle, Microsoft's tests show the DataReader to far outperform working with DataSets and XMLReaders. Table of Contents Applied The real ADO.NET—Building joy of this is the Data-Driven simplicity of Solutions this implementation. All you have to do is implement the GetEnumerator()

method and return a DbEnumerator object. Because you're implementing a standard .NET interface, there's a Introduction related1object that knows how to work with it; therefore, there's no reason for you to implement a custom Chapter - ADO.NET Basics enumerator for your data provider. Chapter 2 - Data Components in Visual Studio .NET Chapter 3


- ADO.NET in Connected Environments Object Creating the PipedDataAdapter

Chapter 4 Chapter 5

- Handling ADO.NET Events Finally,6the- PipedDataAdapter object is where it all comes together. This object provides the layer between the Chapter Integrating XML with ADO.NET

data source and Binding the DataSet. This object defines what operation should be performed to fill the DataSet Chapter 7 - Data and Windows Formsalso Data-Bound Controls with data how to goand about updating the data source to reflect changes made to the DataSet in your data Chapter 8 and - Constraints Data Relations source.9 Chapter


Chapter 10 - inherits WorkingDbDataAdapter with the ODBC .NET Provider This object to Data get the utility of methods such as Fill(). It also implements the Chapter 11 Stored Procedures and Views IDbDataAdapter interface to define what IDbCommands (the interface that defines a single operation on the Chapter 12 - Oracle, SQLXML, and Other Data Providers data source) perform operations on the.NET DataSet. Chapter 13 - Developing a Custom Data Provider

The four points ofDatabase interest in thisApplications implementation the SelectCommand,InsertCommand, Chapter 14main - Developing Web using are ASP.NET UpdateCommand, and DeleteCommand properties. You'll probably recall the names of these commands from Chapter 15 - Using ADO.NET in Xml Web Services the first16 few chaptersServer of this Controls book. Each of these commands, once defined, allows any alteration made in the data Chapter - ASP.NET and Data Binding source or DataSet to be reflected in the other. Listing 13-5 shows the PipedDataAdapter object.


Listing 13-5: The PipedDataAdapter Object


Imports System Imports System.Data Chapter 22 - SQL Server and ADO.NET: Notes on Performance Imports System.Data.Common Appendix A - Relational Databases: Some Basic Concepts Imports System.IO Appendix B - Commonly Used SQL Statements Imports PipedDataProvider Chapter 21 - Messaging

Appendix C - ADO.NET Frequently Asked Questions Index Namespace AppliedADO.DataProvider List of Figures Public Class PipedDataAdapter List of TablesInherits DbDataAdapter List of Listings Implements IDbDataAdapter List of Sidebars Public Sub New()

End Sub Public Sub New(ByRef cmd As PipedDataCommand) _SelectCommand = cmd End Sub Private Sub NotSupported() Throw New NotSupportedException() End Sub Protected Overrides Function CreateRowUpdatingEvent(ByVal row As DataRow, _

ByVal cmd As IDbCommand, ByVal stmtType As StatementType, ByVal mapping _ Applied ADO.NET: Building Data-Driven Solutions As DataTableMapping) As RowUpdatingEventArgs ISBN:1590590732 by Mahesh Chand and NotSupported() David Talbot Apress © 2003 (928 pages) End Function This textOverrides provides extensive coverage of ADO.NET technology Protected Function CreateRowUpdatedEvent(ByVal row As DataRow, _ including ADO.NET internals, namespaces, and ByVal cmd As IDbCommand, ByVal stmtType Asclasses, StatementType, ByVal mapping _ interfaces, and takes a comprehensive look at XML As DataTableMapping) namespaces As and RowUpdatedEventArgs classes, and how to integrate both with NotSupported() ADO.NET. End Function Table of Contents Protected Overrides Sub OnRowUpdated(ByVal value As RowUpdatedEventArgs) Applied ADO.NET—Building Data-Driven Solutions Introduction End Sub Chapter 1 -Protected ADO.NET Basics Overrides Sub OnRowUpdating(ByVal e As RowUpdatingEventArgs) Chapter 2 -End Data Sub Components in Visual Studio .NET Chapter 3


Chapter 4

As IDbCommand -Private ADO.NET in_SelectCommand Connected Environments

Chapter 5

_InsertCommand As IDbCommand -Private Handling ADO.NET Events

Chapter 6

-Private Integrating_UpdateCommand XML with ADO.NET As IDbCommand

Chapter 7

_DeleteCommand IDbCommand -Private Data Binding and Windows FormsAs Data-Bound Controls

Chapter 8


Public Property SelectCommand() As IDbCommand Implements _ - ADO.NET Exception Handling IDbDataAdapter.SelectCommand Chapter 10 - Working with the ODBC .NET Data Provider Get Chapter 11 - Stored Procedures and Views Return _SelectCommand Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers End Get Chapter 13 - Developing a Custom Data Provider Set(ByVal Value As IDbCommand) Chapter 14 - Developing_SelectCommand Database Web Applications using ASP.NET = Value Chapter 15 - UsingEnd ADO.NET in Xml Web Services Set Chapter 16 -End ASP.NET Server Controls and Data Binding Property Chapter 9

Chapter 17 - Building Real-World Web Applications Chapter 18 -Public Object-Relational Property Mapping InsertCommand() in .NET As IDbCommand Implements _

IDbDataAdapter.InsertCommand Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Get Interoperability and ADO.NET Chapter 21 - Messaging Return _InsertCommand

End Get Chapter 22 - SQL Server and ADO.NET: Notes on Performance Set(ByVal Value IDbCommand) Appendix A - Relational Databases: Some As Basic Concepts _InsertCommand = Value End Set Appendix C - ADO.NET Frequently Asked Questions End Property Index Public Property UpdateCommand() As IDbCommand Implements _ List of Figures IDbDataAdapter.UpdateCommand List of Tables Get List of Listings Return _UpdateCommand List of Sidebars End Get Set(ByVal Value As IDbCommand) _UpdateCommand = Value End Set End Property Appendix B - Commonly Used SQL Statements

Public Property DeleteCommand() As IDbCommand Implements _ IDbDataAdapter.DeleteCommand Get Return _DeleteCommand End Get Set(ByVal Value As IDbCommand)

_DeleteCommand = Value Applied End SetADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot End Property Apress © 2003 (928 pages)

End ClassThis text provides extensive coverage of ADO.NET technology End Namespaceincluding ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Testing the PipedDataProvider Application

Table of Contents


Creating a test case for the PipedDataProvider application is a simple one. It's simply a DataGrid and a single button that loads the pipeddata.txt file, fills a DataTable with its data, and then binds it to the DataGrid.


- ADO.NET Basics

Chapter 2 - Data Components in Visual Studio .NET This example highlights how little is required in the front-end code that's forever simplified by the encapsulated Chapter - ADO.NET in Disconnected code in3your custom data provider. AEnvironments piped data file is loaded, parsed, and displayed in just a few lines of code. Chapter - ADO.NET in PipedDataProvider Connected Environments Listing 413-6 shows the application. Chapter 5

- Handling ADO.NET Events Listing613-6: The PipedDataProvider Test Case Chapter - Integrating XML with ADO.NET Chapter 7


ChapterPrivate 8 - Constraints Sub LoadButton_Click(ByVal and Data Relations sender As System.Object, _

ByVal9 e -As System.EventArgs) Chapter ADO.NET Exception Handling Handles LoadButton.Click adapter New PipedDataAdapter() Chapter 10 -Dim Working with theAs ODBC .NET Data Provider Chapter 11 -adapter.SelectCommand Stored Procedures and Views = New PipedDataCommand("ALL", New _

PipedDataConnection("../../pipeddata.txt")) Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers reader As System.Data.IDataReader Chapter 13 -Dim Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Dim data As New DataTable() adapter.Fill(data) Chapter 16 - ASP.NET Server Controls and Data Binding DisplayGrid.DataSource = data Chapter 17 - Building Real-World Web Applications End Sub Chapter 15 - Using ADO.NET in Xml Web Services


Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter - Messaging Figure 21 13-4 shows the output of this program. Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 13-4: The output of the PipedDataProvider application

Building DebuggingApplied Your ADO.NET: Custom DataData-Driven ProviderSolutions by Mahesh Chand and David Talbot

ISBN:1590590732

The most common problem you're trying to build your first data provider is simply getting all the Apress © 2003when (928 pages) interfaces implemented! Because of the strong interdependency the interfaces, you won't have the This text provides extensive coverage of ADO.NET among technology luxury of starting including with a small program that compiles, which you can then incrementally "grow." ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML classes, howoftowhat integrate One way to solvenamespaces this problemand is to make and a note nameboth you with intend on giving each of your ADO.NET. interfaces. Another helpful solution is to take a data provider implementation, such as the one in this chapter, and change each object to then work with your custom data source. Table of Contents

Additionally, you can also build in sections and wrap each object in a test case. For example, implement

Applied ADO.NET—Building Data-Driven theConnection object first and writeSolutions a test case that exercises each of the APIs to make sure you're Introduction getting predictable results. Then implement the IDbCommand object with a related test case to make it's Chapter ADO.NET Basics working1 as- well. Doing this will require a little more coding, but it will likely save you more time in Chapter 2 - than Data trying Components Visual Studio .NET debugging to traceinthe needle in the haystack. Chapter 3

- ADO.NET in Disconnected Environments Finally,4if you're serious about debugging your data provider, add trace logging at the entry and exit of each Chapter - ADO.NET in Connected Environments

method. can be ADO.NET as simpleEvents as writing to the debug stream or as sophisticated as writing to the Chapter 5 This - Handling

Windows event log. This data can be valuable in performing a postmortem on your application when it - Integrating XML with ADO.NET crashes.

Chapter 6 Chapter 7


Chapter 8


Chapter 9



Summary


ISBN:1590590732

Developing a custom data provider can be a little difficult to understand at first because of the number of Apress © 2003 (928 pages) interfaces involved, but with an understanding of whatofeach interface does, creating a custom provider is This text provides extensive coverage ADO.NET technology fairly easy. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML and classes, howthe to integrate both with With the ability tonamespaces define a custom providerand within ADO.NET Framework, you can develop custom ADO.NET. components to represent your custom data sources and leverage all of the .NET data technologies such as DataSets and data binding. Table of Contents

In the next chapter, we discuss the basics of writing Web applications using ASP.NET. As you read it, think

Applied ADO.NET—Building Solutions through how you can useData-Driven the PipedDataProvider application created in this chapter within your Web Introduction application. Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 14: Developing Database Web Applications ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) using ASP.NET This text provides extensive coverage of ADO.NET technology including internals, classes, As the programming worldADO.NET moves toward thenamespaces, Internet these days, and it's becoming important for developers interfaces, and takes a comprehensive look at XML to be able to create Web applications and Web services. The Microsoft .NET Framework enables you to namespaces and classes, and how to integrate both with develop, maintain, and deploy reliable and high-performance Web applications and Web services. ADO.NET.

This chapter starts with an overview of ASP.NET and how to install it, followed by a simple Web application development using Visual Studio .NET (VS .NET). After that it discusses the Web Forms Table of Contents controls and how to use them. The Web Forms' DataGrid control is a useful control to develop WebApplied ADO.NET—Building Data-Driven Solutions based database applications. You can bind a DataSet to the DataGrid control as did for a Windows Introduction Forms'DataGrid control. Chapter 1 - ADO.NET BasicsThis chapter also discusses how to fill data to a DataGrid and how to develop powerful Web-based database applications using the DataGrid control. It also discusses how to enable - Data Components in Visual Studio .NET paging in a DataGrid control. At the end of the chapter you'll see how to develop a guest book for your Chapter 3 - ADO.NET in Disconnected Environments Web site using ASP.NET. Chapter 2 Chapter 4


Chapter 5


Introducing ASP.NET - Integrating XML with ADO.NET

Chapter 6 Chapter 7


Writing database Web applications using ADO.NET in VS .NET is similar to writing Windows applications. Chapter 8 - Constraints and Data Relations The Microsoft .NET Class Library provides a set of server-side controls, which you can treat as Windows Chapter 9 - ADO.NET Exception Handling controls. To create a Web application, all you have to do is create a simple project, drag server-side Chapter 10 - Working with the ODBC .NET Data Provider controls onto a Web form, set their properties, and write event handlers. In this chapter, you'll first develop Chapter 11Web - Stored Procedures a simple application and and see Views how the ASP.NET model works with Visual Basic .NET (VB .NET) and Chapter 12 Oracle, SQLXML, and Data Providers other .NET languages. After thatOther you'll.NET concentrate on ASP.NET and see how to write some real-world Chapter 13 Web - Developing a Custom Providerand VB .NET. database applications usingData ADO.NET Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

ASP.NET Platform Requirements

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications The following operating systems support ASP.NET: Windows XP, Windows 2000 Server, and Windows Chapter 18 - Object-Relational Mapping in .NET Information Services (IIS) 4 or later. Also, you must have the NT 4 (running Service Pack 6a) with Internet Chapter 19 - Mapped Objects: Performance Considerations and Data Binding .NET Software Development Kit (SDK) installed on the server. Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

ASP.NET Language Support

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix - Relational Databases: Some Basic to Concepts You canAuse any .NET-supported language write ASP.NET applications, including C#, VB .NET, and Appendix JScript. B As- this Commonly book isUsed aboutSQL VBStatements .NET, the other languages are beyond the scope of this book. Appendix C - ADO.NET Frequently Asked Questions

Installing ASP.NET

Index

List of Figures

List You of can Tables develop and run ASP.NET applications on Windows 2000 or Windows XP operating systems.

ASP.NET ships with VS .NET. For developers who don't have VS .NET, ASP.NET comes in a separate List of Listings package, which can be downloaded from the Microsoft's Web site (www.microsoft.com). If you want to List of Sidebars develop ASP.NET mobile-enabled applications for Pocket PC or cellular phones, you need to install ASP.NET Mobile Internet Toolkit, which you can also download from Microsoft Web site.

ASP.NET Editors We'll be using VS .NET to develop the applications in this chapter. However, like most languages in the .NET family, you can develop ASP.NET applications using any text editor and command-line compiler. After compiling, you copy your file manually to IIS to deploy the application. The advantage of using VS .NET is that it provides you with a visual Integrated Development Environment (IDE) to drag and drop controls onto a page and view the Hypertext Markup Language (HTML) code in an HTML editor. Other features are IntelliSense and syntax checking. In summary, you can use VS .NET to compile, debug, and

deploy your application.


ISBN:1590590732 by Mahesh andVS David Talbot Note ASP.NET editors, Chand including .NET, provide What-You-See-Is-What-You-Get (WYSIWYG) © 2003 (928Graphical pages) supportApress for developing User Interface (GUI) applications by dropping controls on the Web Forms pages. This text provides extensive coverage of ADO.NET technology

including ADO.NET internals, namespaces, classes, and interfaces, takes a comprehensive XML Microsoft has also releasedand a lightweight, easy-to-use,look and at free ASP.NET development tool (including and classes, and how to integrate with editor) for non-VSnamespaces .NET developers. You can find more detailsboth about this tool on the www.asp.net Web ADO.NET. site.

ASP.NET: An Evolution of ASP

Table of Contents


ASP.NET, previously called ASP+, is not just the next version of ASP. It is a new programming model Introduction based on .NET Framework for developing Web applications. Although ASP.NET syntaxes are Chapter 1 Microsoft's - ADO.NET Basics taken from the ASP.NET takes full advantage of Microsoft's Common Language Runtime Chapter 2 - ASP, Data Components in model Visual Studio .NET (CLR) and services. developers have the flexibility to choose any .NET-supported language Chapter 3 - its ADO.NET in Therefore, Disconnected Environments to write4ASP.NET applications. Chapter - ADO.NET in Connected Environments Chapter 5

- Handling ADO.NET Events The main advantages of the ASP.NET model are the following:

Chapter 6


Chapter 7 - Data Data-Bound Controls ASP.NET is Binding simple and andWindows flexible:Forms Developing ASP.NET applications using VS .NET is similar to Chapter 8 - Constraints and Data Relations developing Windows applications. VS .NET offers you a set of controls to use with ASP.NET. You just Chapter 9 to - ADO.NET need drag andException drop the Handling controls onto a Web Form, write events corresponding to the controls, and Chapter 10 - Working ODBC .NET Provider compile and runwith the the program. OtherData features include simple client authentication, security, Chapter 11 - Storedand Procedures and Views deployment, site configuration. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

ASP.NET is language independent: You can choose any language that supports .NET, including C#, VB, VBScript, and JScript.



ASP.NET supports data binding: ASP.NET offers you a set of data-binding controls such as the Chapter 17 - Building Real-World Web Applications

DataGrid,DataList, and others. You can bind data with these controls in a similar fashion as you do in any Windows Forms application.



ASP.NET has enhanced performance and scalability: ASP.NET code is not interpreted like Chapter 21 - Messaging traditional pages. pageson arePerformance compiled on the server in a .NET assembly. It takes Chapter 22 - SQLASP Server and ASP.NET ADO.NET: Notes advantage of early binding, just-in-time native optimization, and caching services. Appendix A - Relational Databases: Some Basiccompilation, Concepts ASP.NET also works in SQL clustered and multiprocessor environments. Appendix B - Commonly Used Statements Appendix C - ADO.NET Frequently Asked Questions Index ASP.NET is browser independent: If you ever programmed in previous versions of ASP, you've List ofprobably Figures had problems running ASP pages in browsers other than Internet Explorer. ASP.NET is List ofbrowser Tables independent. It automatically checks what browser you're using and produces HTML at List ofruntime Listings accordingly. List of Sidebars

Web Forms and Web Services Web Forms is a term Microsoft introduced when it released its ASP+ framework for developing Web applications using the ASP model. Similar to Windows applications and services, you can also write Web applications and services. A Web application is a distributed application, which allows you to work and distribute functionality over the Web and provides user interfaces. Using Web Forms controls, you can write Web GUI applications similar to Windows applications. ASP.NET's Web Forms provide you with the ability to build Web-based GUI applications. Web Forms include Web pages (also called ASP.NET pages or Web Forms pages) and GUI components (sometimes

calledserver controls) such as a TextBox,Button,ListBox,DataGrid, and so on. ASP.NET Applied ADO.NET: Building Data-Driven Solutions provides the flexibility to add these controls to an ASP.NET page at runtime as well as at design-time. VS ISBN:1590590732 by Maheshfeatures Chand and David Talbot .NET provides design-time to develop applications in no time. You add controls to a page by Apress © 2003 (928 pages) dragging controls from the Toolbox to the page and then setting the controls' properties and events. Web This provides extensive coverage of ADO.NET Forms also provide a text method for using the Codebehind directivetechnology to separate your data from the code. In including ADO.NET internals, namespaces, classes, and other words, you can write code in a separate file from the controls.

interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Web services areADO.NET. applications that perform a certain task; they can be used by a single application as well

as distributed on the Web. However, Web services don't usually have a user interface like a normal application would. Chapter 15 covers Web services. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Building Data-Driven Solutions DevelopingApplied YourADO.NET: First ASP.NET Web Application by Mahesh Chand and David Talbot

ISBN:1590590732

Before discussingApress the ASP.NET © 2003 (928model pages) in more depth, we'll show you how to develop your first ASP.NET application using This VS .NET. In this create a simple technology Web application using VS .NET. You'll text providesexample, extensive you'll coverage of ADO.NET add a Button, aincluding TextBox, and a ListBox control to a Web page and then add the TextBox contents ADO.NET internals, namespaces, classes, and interfaces, andclick takes a comprehensive look at XML to the ListBox on the button event. namespaces and classes, and how to integrate both with ADO.NET.

Creating a Web Application Project

Table of Contents Creating a new ASP.NET Web application using VS .NET is simple. First create a new project using File Ø Applied Data-Driven Solutions NewØ ADO.NET—Building Project Ø Visual Basic Projects and then select the ASP.NET Web Application template (see Introduction Figure 14-1). Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure 14-1: The FirstWebApplication project


Chapter Mapped Performance Considerations anddefault Data Binding As you 19 see- in FigureObjects: 14-1, the Location box shows you the option of http://localhost and the Chapter 20 - name. COM Interoperability and ADO.NET application Here, localhost represents the default IIS server running on your local machine. The Chapter default 21 virtual - Messaging directory for localhost is C:\Inetpub\wwwroot. Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Clicking the OK button creates a new directory, FirstWebApplication, in the server's virtual directory. It also creates a new Web application and sends you to the default WebForm1.aspx page, as shown in Appendix B - Commonly Used SQL Statements Figure 14-2. Appendix A - Relational Databases: Some Basic Concepts Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Figure 14-2: DefaultWebForm1.aspx page

Chapter 6

- Integrating XML with ADO.NET From here edit your page's HTML. you see inControls the left-bottom corner of Figure 14-2, there are Chapter 7 - you Datacan Binding and Windows FormsAs Data-Bound

two modes andRelations HTML. Click the HTML button to edit the code, as shown in Figure 14-3. Chapter 8 - available: ConstraintsDesign and Data Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Figure 14-3: HTML view of WebForm1.aspx



The HTML view shows you the HTML code of a page, its controls, and control properties. The HTML editor Index also you edit the HTML manually. List of let Figures List of Tables

Now, if you switch to the design mode and right-click the page, you'll get several options: View HTML Source, Build Style, View in Browser, View Code, Synchronize Document Outline, and so on (see Figure List of Sidebars 14-4). List of Listings


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - 14-4: Working the ODBC .NETright-click Data Provider Figure Anwith ASP.NET page's options Chapter 11 - Stored Procedures and Views Chapter You can 12set - Oracle, a page's SQLXML, properties and by Other selecting .NET Data Properties Providers from the right-click menu. The Properties menu

opens the Pages window. As you can see from Figure 14-5, there are three tabs Chapter 13 -Document DevelopingProperty a Custom Data Provider available the Properties window: General, Colorusing and ASP.NET Margins, and Keywords. Most of the properties are Chapter 14 in - Developing Database Web Applications self-explanatory. the General merits explanation. The Page Layout property has two options, Chapter 15 - Using On ADO.NET in Xml tab, Webone Services GridLayout FlowLayout. GridLayout is when you want drop controls to the page and reposition them. If Chapter 16 - and ASP.NET Server Controls and Data Binding you want add textReal-World to the page, youApplications should set the page layout to FlowLayout; otherwise you won't be Chapter 17 to - Building Web

able to add text to the page. After setting the Page Layout property to FlowLayout, the editor works as a text editor.



Figure 14-5: An ASP.NET document's page properties

Adding Web Controls to a Web Form Similar to the Windows control Toolbox, VS .NET provides a Web Forms control Toolbox. You can open the Toolbox by selecting View Ø Toolbox. The Web Forms Toolbox looks like Figure 14-6. The Web

Forms category of the Toolbox contains form controls, and the HTML category contains HTML controls. Applied ADO.NET: Building Data-Driven Solutions The Data category provides the same data components you've seen in the Windows application Toolbox. ISBN:1590590732 by Maheshdata Chand and David Talbot It has the same ADO.NET components, including Connection, DataAdapter,DataSet, Apress © 2003 (928 pages) DataView, and DataViewManager.Figures 14-6 shows the Web Forms controls. Similar to Web forms Thisthe text provides coverage ADO.NET technology controls, if you click HTML tab,extensive you can see HTMLofcontrols. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Figure WebDatabases: Forms controls Appendix A - 14-6: Relational Some Basic Concepts Appendix B - Commonly Used SQL Statements

For the applications in this chapter, we'll be using the Web Forms controls.


Index OK, now you can switch the page back to the design mode and GridLayout mode (if you changed its List of Figures modes) and add a Button, a TextBox, and a ListBox to the form by dragging these controls from the List of Web Tables Forms toolbox to WebForm1.aspx. The page should now look like Figure 14-7. List of Listings List of Sidebars


ISBN:1590590732



Figure WebForms1.aspx Design mode after adding Web Forms controls Chapter 1 - 14-7: ADO.NET Basics Chapter 2


Chapter 3


Setting- ADO.NET Control in Connected Properties Environments

Chapter 4 Chapter 5

- Handling ADO.NET Events The next is to add XML some textADO.NET to the page and change some of the controls' properties. To add text to Chapter 6 step - Integrating with

the page, first you need to change the page layout to FlowLayout in the Properties window, which you - Data Binding and Windows Forms Data-Bound Controls open by right-clicking the page and selecting Properties. Now add a heading to the page. For this Chapter 8 - Constraints and Data Relations example, add two lines to the page and set different fonts and font sizes of these lines. You can also set Chapter 9 - ADO.NET Exception Handling some of the Button control's properties (see Figure 14-8). Chapter 7


Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables

Figure 14-8: Properties window for the Web controls

List of Listings

List of Sidebars

Specifically, we changed the border, background color, font, and foreground color of these controls. As you can see, changing these properties is similar to changing them for Windows applications. The final page with these properties looks like Figure 14-9.


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3

- ADO.NET in Disconnected Environments Figure Final of theEnvironments Web application after changing some control properties Chapter 4 - 14-9: ADO.NET in page Connected Chapter 5


Chapter 6


Using Document Outline - Data Binding and Windows Forms Data-Bound Controls

Chapter 7 Chapter 8


Another nice feature of the VS .NET IDE is that you can synchronize a Web page's controls with its - ADO.NET Exception Handling contents in the Document Outline viewer. This is useful when you're developing a Web application with Chapter 10 - Working with the ODBC .NET Data Provider hundreds of controls; it can be hard to keep track of all the controls, HTML tags, and other page contents. Chapter 11 - Stored Procedures Viewsyou to manage a page's contents in a tree format. The tree format The Document Outline viewerand enables Chapter 12 Oracle, SQLXML, and Other .NET they're Data Providers displays all the page elements in the order called in the page. You can open the Document Outline Chapter - Developing aa Custom Data ProviderSynchronize Document Outline. Clicking this menu item viewer 13 by right-clicking page and selecting Chapter 14 the - Developing Database Applications launches Document Outline Web viewer in the left using pane ASP.NET (see Figure 14-10). As you can see, the tree view Chapter - Using Xml Webthe Services displays15the page ADO.NET contents,inincluding form, button, text box, and paragraph. If you click a control in the Chapter Document 16 -Outline ASP.NET viewer, ServeritControls selects and the corresponding Data Binding control in the form. And, vice versa, if you select a control17 in the form, the viewer selects that control in the tree view. Chapter - Building Real-World Web Applications Chapter 9

Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 14-10: Document Outline viewer You can also use the Document Outline viewer's right-click menu to cut, paste, delete, view the code, and view the properties of these controls. The right-click menu's View Code option displays the code of the page. Not only that, but now you'll see one more thing. Select the HTML view of your page, and you can move to specific HTML tags using the Document Outline viewer. As you can see from Figure 14-11, the tree view displays all the code of an HTML page in a nested structure as they're organized in the original code.


ISBN:1590590732



Figure 14-11: HTML view of the Document Outline viewer

Chapter 1

- ADO.NET Basics

Chapter - Data Components in Visual Studio .NET So, the2point is that you can find and organize your HTML code and controls from the Document Outline Chapter viewer 3instead - ADO.NET of looking in Disconnected for a tag in the Environments file manually. Chapter 4


Writing- Handling Code ADO.NET on theEvents Button Click Event Handler

Chapter 5 Chapter 6

- Integrating XML with ADO.NET The last of this tutorial to add an event handler forControls the button and write code to add some TextBox Chapter 7 step - Data Binding andisWindows Forms Data-Bound

text to the You a control event similar to Windows applications. You can just double-click Chapter 8 -ListBox. Constraints andadd Data Relations the button add a button click Handling event handler. Chapter 9 -toADO.NET Exception Chapter 10 - Working with the ODBC .NET Data Provider

This action adds the Button1_Click method to the WebForm1.aspx.vb class, which hosts the code for the page controls and events. Now write a line of code to add the TextBox contents to the list box. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Specifically, add the bold line in the following section to the Button1_Click method: Chapter 11 - Stored Procedures and Views



Private Sub Button1_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button1.Click Chapter 16 - ASP.NET Server Controls and Data Binding ListBox1.Items.Add(TextBox1.Text.ToString()) Chapter 17 - Building Real-World Web Applications End Sub Chapter 15 - Using ADO.NET in Xml Web Services

Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Note can also see the code using the View Code option of the page's right-click menu. Chapter 21 You - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Now compile and run the project. The output of the program looks like Figure 14-12. Clicking the Add button adds the TextBox contents to the list box.



Figure 14-12: Output of your first Web application

After finishing this application, you can see the power and flexibility of ASP.NET and the VS .NET IDE. Applied ADO.NET: Building Data-Driven Solutions You've just developed a nice ASP.NET Web application without any knowledge of ASP.NET and just by ISBN:1590590732 by Mahesh writing only one line of code.Chand and David Talbot Apress © 2003 (928 pages)



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions Creating Your First ADO.NET Web Application by Mahesh Chand and David Talbot

ISBN:1590590732

You've already seen how to develop an ASP.NET application using VS .NET. Now you'll see how to Apress © 2003 (928 pages) develop databaseThis applications using ADO.NET and ASP.NET. Totechnology start creating your first ADO.NET text provides extensive coverage of ADO.NET application, you'llincluding create a ADO.NET Web Application project as you did in the previous tutorial. In this example, you'll internals, namespaces, classes, and interfaces, and Northwind takes a comprehensive look at XML read data from the SQL Server database and view data in few data-bound controls. After namespacesadd andaclasses, to integrate bothtowith creating a Web application, ListBoxand andhow a DataGrid control the Web page. In this application, ADO.NET. you'll fill these controls with data from the database. After dragging these controls from the Web Forms control Toolbox and dropping it on the page, you write the code in Listing 14-1 on the Page_Load event. You can add a Page_Load event by typing the code Applied ADO.NET—Building Data-Driven Solutions directly into the Codebehind.vb file or by double-clicking on the page.


Chapter - ADO.NET Listing114-1: Filling Basics Data from a Database to Data-Bound Controls Chapter 2 - Data Components in Visual Studio .NET Chapter 3


Private Sub Page_Load(ByVal sender As System.Object, _ - ADO.NET in Connected Environments ByVal e As System.EventArgs) Handles MyBase.Load Chapter 5 - Handling ADO.NET Events Dim ConnectionString As String = "user id=sa;password=;" & _ Chapter 6 "Initial - Integrating XML with ADO.NET Catalog=Northwind;" & _ Chapter 7 "Data - Data Source=MCB;" Binding and Windows Forms Data-Bound Controls ChapterDim 8 -conn Constraints and Data Relations = New SqlConnection(ConnectionString) As SqlConnection Chapter'9 Open - ADO.NET Exception Handling the connection ChapterIf 10 (conn.State - Working with the .NET Data Provider ODBC ConnectionState.Open) Then Chapter 11 conn.Open() - Stored Procedures and Views ChapterEnd 12 -If Oracle, SQLXML, and Other .NET Data Providers Dim adapter SqlDataAdapter Chapter 13 - DevelopingAs a Custom Data Provider = New SqlDataAdapter _ ("SELECT EmployeeID, LastName, Chapter 14 - Developing Database Web ApplicationsFirstName using ASP.NETFROM Employees", conn) Dim ds As DataSet = New DataSet() Chapter 15 - Using ADO.NET in Xml Web Services "Employees") Chapteradapter.Fill(ds, 16 - ASP.NET Server Controls and Data Binding ' Bind data set to the control Chapter 17 - Building Real-World Web Applications ' Set DataSource property of ListBox as DataSet's DefaultView Chapter 18 - Object-Relational Mapping in .NET ListBox1.DataSource = ds Chapter 19 - Mapped Objects: Performance Considerations and Data Binding ListBox1.SelectedIndex = 0 Chapter 20 - COM Interoperability and ADO.NET ' Set Field Name you want to get data from Chapter 21 - Messaging ListBox1.DataTextField = "FirstName" Chapter'DataGrid1.DataSource 22 - SQL Server and ADO.NET:= Notes on Performance ds.DefaultViewManager Appendix A Relational Databases: Some Basic Concepts DataGrid1.DataSource = ds Appendix - Commonly Used SQL Statements ' BDataGrid1.DataBind() Appendix C - ADO.NET Frequently Asked Questions DataBind() Index ' Close the connection List of Figures If (conn.State = ConnectionState.Open) Then conn.Close() List of Tables End If List of Listings End Sub List of Sidebars Chapter 4

Note We're using a SQL Server database and the SqlClient data provider, which means we import the System.Data.SqlClient namespace to the application. As you can see, this code looks familiar. First you create a Connection object with the Northwind database. After that you create a DataAdapter and select the EmployeeID, FirstName, and LastName columns from the Employees table. Then you create a DataSet object and fill it using the DataAdapter'sFill method. Once you have a DataSet, you set the DataSet as the ListBox's DataSource property and set SelectIndex as 0. The SelectIndex property represents the index of the column from a DataSet you want to display in the control. The field name of the column is FirstName.

You also set the DataSource property of DataGrid control as DataSet. At the end you call the Applied Data-Driven DataBind method of theADO.NET: ListBox.Building This method binds theSolutions data to the data-bound controls. by Mahesh Chand and David Talbot

ISBN:1590590732

The output looks Apress like Figure © 200314-13. (928 pages) As you can see, the ListBox control displays data from the FirstName column of text the Employees table, and DataGrid displays all three columns. This provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9

ADO.NET Exception Handling Figure- 14-13: Your first ADO.NET Web application


In Figure youSQLXML, may notice DataGrid looks different. You can set a DataGrid format by Chapter 1214-13, - Oracle, and the Other .NET Dataformat Providers using the Format option of the Properties Chapter 13 Auto - Developing a Custom Data Provider window. Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

AppliedServer-Side ADO.NET: Building Data-Driven Solutions Using ASP.NET Controls by Mahesh Chand and David Talbot

ISBN:1590590732

The Microsoft .NET Framework provides Apress © 2003 (928 pages) a rich set of server-side controls for developing Web applications. YouThis cantext addprovides these controls to Web Forms pages just as you add Windows controls to a extensive coverage of ADO.NET technology form. Server-sideincluding controls ADO.NET are ofteninternals, called server controls or Web Forms controls. There are four types of namespaces, classes, and interfaces, and takes a Web comprehensive look atvalidation XML server controls: HTML server controls, server controls, controls, and user controls. namespaces and classes, and how to integrate both with ADO.NET.

HTML Server Controls

Table of developers Contents will be familiar with old HTML controls, which they use to write GUI applications in HTML Applied Data-Driven Solutions HTML.ADO.NET—Building These controls are the same HTML controls; you can run these controls on the server by defining

therunat="Server" attribute. Note that if you do not set this attribute, the HTML control acts as a Introduction normal1HTML control.Basics You may prefer this in some situations, as the HTML controls work without requiring Chapter - ADO.NET a round-trip to theComponents server. These control names start with Html.Table 14-1 defines some of these Chapter 2 - Data in Visual Studio .NET controls. Chapter 3 - ADO.NET in Disconnected Environments Chapter 4


Table 14-1: HTML Server Controls Chapter 5 - Handling ADO.NET Events Chapter 6 - Integrating XML with ADO.NET CONTROL DESCRIPTION Chapter 7 - Data Binding and Windows Forms Data-Bound Controls

HtmlForm Creates an HTML form control, used as a placeholder of other Chapter 8 - Constraints and Data Relations Chapter 9

controls - ADO.NET Exception Handling

Chapter 10 - Working with the ODBC .NET Data Provider HtmlInputText Creates an input TextBox control used to get input from user Chapter 11 - Stored Procedures and Views

HtmltextArea

Creates a multiline TextBox control


Chapter 13 - Developing a Custom Data Provider HtmlAnchor Creates Web navigation Chapter 14 - Developing Database Web Applications using ASP.NET

HtmlButton

Creates a Button control


Chapter 16 - ASP.NET Server Controls and Data Bindingcontrol that is used to display an image HtmlImage Creates an Image Chapter 17 - Building Real-World Web Applications

HtmlInputCheckBox

Creates a CheckBox control


Chapter HtmlInputRadioButton 19 - Mapped Objects: Performance Creates Considerations a RadioButton andcontrol Data Binding Chapter 20 - COM Interoperability and ADO.NET

HtmlTable


Creates a Table control

HtmlTableRow Chapter 22 - SQL Server and ADO.NET: Creates Notes a row on Performance within a table Appendix A - Relational Databases: Some Basic Concepts

HtmlTableCell

Creates a cell within a row



Web server controls are more powerful than HTML controls because they provide more functionality and

Index are easier to use. Besides some of the basic controls such as Button,TextBox,Label, and List of Figures ASP.NET provides some more powerful controls such as DataGrid, DataList, and CheckBox, List of Tables You'll use these controls throughout this chapter. Table 14-2 describes some of these Calendar. List of Listings controls. List of Sidebars

Table 14-2: Web Server Controls

CONTROL


Label

by Mahesh Chand and David Talbot Represents a label Apress © 2003 (928 pages)

ListBox CheckBox Calender

ISBN:1590590732

This text Represents provides extensive a list box coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Represents check box interfaces, and takes aacomprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.Represents a calendar

ImageButton Table of Contents TableCell

Represents an image button Represents a table cell


Panel Introduction

Represents a panel

Chapter 1 - ADO.NET Basics DateList Represents a data list Chapter 2 - Data Components in Visual Studio .NET

TextBox RepresentsEnvironments a text box Chapter 3 - ADO.NET in Disconnected Chapter 4 Image

- ADO.NET in Connected Environments Represents an image

Chapter 5


CheckBoxList Represents a list box with check boxes - Integrating XML with ADO.NET Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Button Represents a button Chapter 6 Chapter 8


Chapter 9


HyperLink

Represents a hyperlink

Chapter 10 - Working with the ODBC .NET Provider TableRow Represents a Data row of a table Chapter 11 - Stored Procedures and Views

RadioButtonList

Represents a list box with radio buttons

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter DataGrid 13 - Developing a Custom Data Provider Represents a data grid


DropDownList

Represents a drop-down list


Chapter AdRotator 16 - ASP.NET Server Represents Controls and anData ad rotator Binding Chapter 17 - Building Real-World Web Applications

RadioButton

Represents a radio button


LinkButton Represents a link button Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Table


Represents a table

Repeater a repeater Chapter 22 - SQL Server andRepresents ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

You'll see how to use these controls in example applications throughout this chapter.


Validation Controls


Validating user input is one of the important needs for Web applications. These controls provide features to validate user input. Using these controls you can check a required field, a value, a range, a pattern of List of Sidebars characters, and so on. Table 14-3 describes validation controls. List of Listings

Table 14-3: Validation Controls

CONTROL

DESCRIPTION Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot Makes sure that the user does not skip an entry Apress © 2003 (928 pages)

RequiredFieldValidator

CompareValidator This text provides extensive Compares coverageuser of ADO.NET input with technology a value using a comparison including ADO.NET internals, namespaces, andgreater than, and so on operator such asclasses, less than, interfaces, and takes a comprehensive look at XML

namespaces and classes, Checks and howifto integrate both with RangeValidator the user's input falls within a certain range ADO.NET.

RegularExpressionValidator CustomValidator Table of Contents

Checks if the user's input matches a defined pattern Creates your own custom logic

Applied ADO.NET—Building Data-Driven Solutions Introduction - ADO.NET Basics User Controls

Chapter 1 Chapter 2

- Data Components in Visual Studio .NET Besides3 HTML serverincontrols, Web Environments server controls, and validation controls, you can also create your own Chapter - ADO.NET Disconnected

controls4 by- embedding Forms controls. These controls are called custom controls. You create Chapter ADO.NET in Web Connected Environments custom5controls when the available Chapter - Handling ADO.NET Eventscontrols can't provide the functionality you need. For example, if you

want to create a DataGrid control with check boxes, combo boxes, calendars, and date controls, you - Integrating XML with ADO.NET can create a custom control derived from the available controls and then write the additional functionality.

Chapter 6 Chapter 7


Chapter 8


Server -Controls andHandling the .NET Framework Library ADO.NET Exception

Chapter 9


The .NET Framework Library provides the System.Web and its 15 supporting namespaces to define Web classes. These namespaces reside in the System.Web.dll assembly. Before you use any Web Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers namespaces, though, you need to add a reference to the System.Web.Dll assembly and include the Chapter 13 - Developing a Custom Data Provider required namespace in the application. The five major namespaces of the Web series are System.Web, Chapter 14 - Developing Database Web Applications using ASP.NET System.Web.UI, System.Web.UI.HtmlControls, System.Web.UI.WebControls, and Chapter 15 Using ADO.NET System.Web.Services. in Xml Web Services Chapter 11 - Stored Procedures and Views

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications The System.Web Namespace Chapter 18 - Object-Relational Mapping in .NET

TheSystem.Web contains browser-and server-related classes and interfaces. For example, Chapter 19 - Mappednamespace Objects: Performance Considerations and Data Binding theHTTPRequest and HTTPResponse classes provide functionality to make requests for HTTP to Chapter 20 - COM Interoperability and ADO.NET

retrieve and post data on the server through a browser. The HttpApplication class defines the functionality of an ASP.NET application. This namespace also contains the HttpCookie and Chapter 22 - SQL Server and ADO.NET: Notes on Performance HttpCookieCollection classes for manipulating cookies. The HttpFileCollection class provides Appendix A - Relational Databases: Some Basic Concepts access to and organizes files uploaded by a client. You can use the HttpWriter class to write to the Appendix B - Commonly Used SQL Statements server through HttpResponse. Chapter 21 - Messaging

Appendix C - ADO.NET Frequently Asked Questions Index The

System.Web.UI Namespace

List of Figures

The namespace contains classes and interfaces that enable you to develop Web-based List ofSystem.Web.UI Tables GUI similar to Windows GUI applications. This namespace provides classes to create Web List of applications Listings Forms pages and controls. The Control class is the base class for all Web control classes and provides List of Sidebars methods and properties for HTML, Web, or user controls. The Page class represents a Web page requested by the server in an ASP.NET application. It also has classes for data binding with the databound controls such as DataGrid and DataList. You'll see these classes in the examples in this chapter. In addition to these classes, it also includes state management, templates, and validation-related classes.

The System.Web.UI.HtmlControls Namespace This namespace contains HTML control classes (discussed in the "HTML Server Controls" section). Some of this namespace's classes are HtmlButton,HtmlControl,HtmlForm,HtmlImage, HtmlInputText,HtmlTable, and so on.

The System.Web.UI.WebControls Namespace Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Maheshclasses Chand and David This namespace by contains related to Talbot server controls and their supporting classes, as discussed in Apress © 2003 (928 pages) the "Web Server Controls" section of this chapter. Some of the classes are AddRotator,Button, This text provides extensive coverage of ADO.NETHyperLink, technology Image, Label, Calendar,CheckBox, DataGrid, DataList, DropDownList, including ADO.NET internals, namespaces, classes, andBesides the control classes, it also ListBox,ListControl,Panel,Table,TableRow, and TextBox. interfaces, and takes a comprehensive look at XML contains control helper classes. example, the DataGridItem, DataGridColumn, and namespaces andFor classes, and how to integrate both with DataGridColumnCollection classes are helper classes of the DataGrid control, and TableRow, ADO.NET. TableCell,TableCellCollection,TableHeaderCell, and TableItemStyle are helper classes of the Table control.

Table of Contents Applied ADO.NET—Building Data-Driven Solutions The System.Web.Services Namespace Introduction

A Web 1service is an application that sits and runs on the Web server. The System.Web.Service and its Chapter - ADO.NET Basics three helper namespacesSystem.Web.Service.Description, Chapter 2 - Data Components in Visual Studio .NET System.Web.Service.Discovery, and System.Web.Service.Protocol-provides classes to Chapter 3 - ADO.NET in Disconnected Environments build Web 15 covers Web services in more detail. Chapter 4 -services. ADO.NETChapter in Connected Environments Chapter 5


Why Are - Integrating Web Forms XML with ADO.NET Controls Called Server-Side Controls?

Chapter 6 Chapter 7


Microsoft's Framework consists of powerful Web controls. By using these Web controls you can Chapter 8 - .NET Constraints and Data Relations write powerful Web GUI applications similar to desktop applications. You can write code for these controls Chapter 9 - ADO.NET Exception Handling manually, or you can use VS .NET. VS .NET supports the drag-and-drop design-time feature. In other Chapter 10 - Working with the ODBC .NET Data Provider words, you can drag and drop Web Forms controls onto a Web form, set properties by right-clicking a Chapter 11 - Stored Procedures and Views control, and even write event handlers by double-clicking the control as you'd do in Windows GUI Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers applications such as VB. Chapter 13 - Developing a Custom Data Provider

Chapter When a14client - Developing (a Web browser) Database makes Web Applications a call for ausing WebASP.NET control such as a Button or a DataGrid, the

runat="Server" attributein(discussed later in more detail) tells the Web server that the controls will be Chapter 15 - Using ADO.NET Xml Web Services executed the server and Controls they'll send data to the client at run-time after execution. Because the Chapter 16 on - ASP.NET Server and HTML Data Binding execution these control events, methods, and attributes happens on the server, these controls are Chapter 17 -ofBuilding Real-World Web Applications server-side Web controls. The main functionality of these controls includes rendering data from the server Chapter 18 - Object-Relational Mapping in .NET to the client and event handling. (The controls fire events and handle those events.) Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Adding Server-Side Controls to a Web Form



You have ways toDatabases: add serverSome controls to Concepts a Web form. You can use the VS .NET IDE to add server Appendix A two - Relational Basic controls, or you can add controls manually by typing code using the syntax.



Adding Server Controls Using VS .NET

Index

List of Figures Adding server controls using VS .NET is pretty simple. As you have seen in the "Developing Your First List of TablesWeb Application" section of this chapter, you create a new ASP.NET application project, open ASP.NET List Listings drag and drop controls from Toolbox, set properties, and write event handlers for the control. theofToolbox, List of Sidebars

Adding Server Controls Using ASP.NET Syntax The other method of adding server controls to an application is writing the code manually. To add server controls manually, you create a text file and save it with an .aspx extension. .NET utilizes Extensible Markup Language (XML)-like tags to write server controls. A tag should follow XML syntaxes. Every ASP.NET control starts with asp: and a control name. For example, the following line creates a TextBox control:

This line creates a TextBox server control. Every control has a unique ID. In this sample the ID is

TextBox1. The runat="Server" attribute represents that the control will run on the server. Applied ADO.NET: Building Data-Driven Solutions

ISBN:1590590732 by shows Maheshyou Chand David Talbot code without The following code canand write the same the closing tag:

Apress © 2003 (928 pages) text provides extensive coverage of /> ADO.NET technology Providers and Data Binding This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Description interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Solutions Introduction Chapter 1 - ADO.NET Basics Chapter Chapter 3 - ADO.NET in Disconnected Environments Chapter 4 - ADO.NET in Connected Environments Chapter 5


Chapter 6


The next step is to load data to the control. You create a method called FillDataList, which binds data - Data Binding and Windows Forms Data-Bound Controls to the DataList control based on the items specified in ItemTemplate and Chapter 8 - Constraints and Data Relations AlternatingItemTemplate, as shown earlier. Chapter 7 Chapter 9


Chapter You call 10the - Working FillDataList with the ODBC method .NET onData the Provider Page_Load event, as shown in the following code: Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Sub Page_Load Chapter 13 - Developing a Custom Data Provider If not IsPostBack Chapter 14 - Developing Database Web Applications using ASP.NET FillDataList() Chapter End15If- Using ADO.NET in Xml Web Services

End Sub Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Now you write the EditCommand event handler, where you set EditItemIndex of the DataList control to the ItemIndex of DataListCommandEventArgs.Item returned by the EditCommand Chapter 20 - COM Interoperability and ADO.NET handler. After setting EditItemIndex of DataList, you refill data to the control by calling the Chapter 21 - Messaging FillDataList method, as shown in the following code: Chapter 19 - Mapped Objects: Performance Considerations and Data Binding


Sub EditCommandHandler(sender as object, _ args as DataListCommandEventArgs) Appendix C - ADO.NET Frequently Asked Questions dtList.EditItemIndex = args.Item.ItemIndex Index FillDataList() List of Figures End Sub Appendix B - Commonly Used SQL Statements


Onofthe CancelCommand event handler, you simply set EditItemIndex of DataListto -1 and rebind List Sidebars theDataList control: Sub CancelCommandHandler(sender as object, _ args as DataListCommandEventArgs) dtList.EditItemIndex = -1 FillDataList() End Sub

Writing code for the UpdateCommand and DeleteCommand handlers is little tricky. You probably can

guess that on the UpdateCommand handler, you need to find out the index of the current item by using Appliedwhich ADO.NET: Building Data-Driven Solutions DataList.DataKeys, returns the PrimaryKey column's value. Once you know the by Mahesh Chand and David Talbot PrimaryKey, you can easily find out which record you want toISBN:1590590732 update or delete. You can simply construct Apress © 2003it.(928 pages) aSqlCommand and execute This text provides extensive coverage of ADO.NET technology including ADO.NET namespaces, classes, and TheDeleteCommand event handlerinternals, is as follows: interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with dim strId as ADO.NET. string = dtList.DataKeys(args.Item.ItemIndex)

dim sql = "DELETE Categories WHERE CategoryID=@catID" dim cmd as SqlCommand = new SqlCommand(sql, conn) Table of Contents cmd.Parameters.Add("@catID", strId) Applied ADO.NET—Building Data-Driven Solutions conn.Open() Introduction cmd.ExecuteNonQuery() Chapter 1 - ADO.NET Basics conn.Close() Chapter 2 - Data Components = in -1 Visual Studio .NET dtList.EditItemIndex Chapter FillDataList() 3 - ADO.NET in Disconnected Environments Chapter 4


Chapter 5


As you can see from the previous code, you simply get the CategoryID value for the edited item of the - Integrating XML with ADO.NET DataList control. Once you have the CategoryID value, you delete all records that match the Chapter 7 - Data Binding and Windows Forms Data-Bound Controls CategoryID by constructing and executing a DELETEstatement. Chapter 6 Chapter 8


Chapter - ADO.NET Exception On the 9UpdateCommand eventHandling handler, you need to get the values of the CategoryName and Description Chapter 10and - Working with the and ODBC .NET Data Provider statement, as shown in the following code: columns then construct execute an UPDATE Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, =and Other .NET Data Providers dim strId as string dtList.DataKeys(args.Item.ItemIndex) Chapter 13 - Developingas a Custom Data = Provider dim strCatName TextBox args.Item.FindControl("catNameTextBox") Chapter 14 - Developing Database Web Applications using ASP.NET dim strDesc as TextBox = args.Item.FindControl("desTextBox") Chapter 15 - Using ADO.NETCategories in Xml Web Services dim sql = "UPDATE SET CategoryName=@catName, " & _ Chapter " Description=@desc 16 - ASP.NET Server Controls WHEREand CategoryID=@catID" Data Binding

dim cmd as SqlCommand = new SqlCommand(sql, conn) Chapter 17 - Building Real-World Web Applications cmd.Parameters.Add("@catID", strId) Chapter 18 - Object-Relational Mapping in .NET cmd.Parameters.Add("@catName", strCatName.Text.ToString()) Chapter 19 - Mapped Objects: Performance Considerations and Data Binding cmd.Parameters.Add("@desc", strDesc.Text.ToString()) Chapter 20 - COM Interoperability and ADO.NET conn.Open() Chapter 21 - Messaging cmd.ExecuteNonQuery() conn.Close() Appendix A - Relational Databases: Some Basic Concepts dtList.EditItemIndex = -1 Appendix B - Commonly Used SQL Statements FillDataList()


Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables

List ofNote Listings You also set the EditItemIndex of DataList to -1 and call the FillDataList method to List of Sidebars refill the DataList control.

Finally,Listing 16-17 shows the complete code. Listing 16-17: EditableDataList Control Editable DataList

Sub Page_Load Applied ADO.NET: Building Data-Driven Solutions If not IsPostBack ISBN:1590590732 by Mahesh Chand and David Talbot FillDataList() Apress © 2003 (928 pages) End If This text provides extensive coverage of ADO.NET technology End Sub including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Sub FillDataList() namespaces and classes, and how to integrate both with ADO.NET. Dim conn As SqlConnection

Dim adapter As SqlDataAdapter dim connectionString = _ Table of Contents "Data Source=MCB;Initial Catalog=Northwind;user id=sa;password=;" Applied ADO.NET—Building Data-Driven Solutions conn = new SqlConnection(connectionString) Introduction conn.Open() Chapter 1 sql - ADO.NET Basics * FROM Categories" dim = "SELECT Chapter 2 cmd - Data Components in Visual Studio .NET dim as SqlCommand = new SqlCommand(sql, conn) Chapter 3 reader - ADO.NET Disconnected Environments dim asin SqlDataReader = cmd.ExecuteReader() Chapter 4 - ADO.NET in Connected Environments dtList.DataSource = reader Chapter dtList.DataBind() 5 - Handling ADO.NET Events reader.Close() Chapter 6 - Integrating XML with ADO.NET conn.Close() Chapter 7 - Data Binding and Windows Forms Data-Bound Controls End Sub Chapter 8 - Constraints and Data Relations Chapter 9

- ADO.NET Exception Handling Sub EditCommandHandler(sender as Provider object, _ Chapter 10 - Working with the ODBC .NET Data

args as DataListCommandEventArgs) ' code here Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers End Sub Chapter 13 - Developing a Custom Data Provider Sub CancelCommandHandler(sender as object, _ Chapter 14 - Developing Database Web Applications using ASP.NET args as DataListCommandEventArgs) Chapter 15 - Using ADO.NET in Xml Web Services ' code here Chapter 16 - ASP.NET Server Controls and Data Binding End Sub Chapter 11 - Stored Procedures and Views

Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET as object, _ Sub DeleteCommandHandler(sender Chapter 19 -DataListCommandEventArgs) Mapped Objects: Performance Considerations and Data Binding args as Chapter 20 here - COM Interoperability and ADO.NET ' code Chapter End Sub 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Sub UpdateCommandHandler(sender object, _ Appendix A - Relational Databases: Some Basic as Concepts args as Appendix B -DataListCommandEventArgs) Commonly Used SQL Statements ' code here Frequently Asked Questions Appendix C - ADO.NET End Sub Index List of Tables List of Listings List of Sidebars List of Figures

Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) text provides extensive coverage of ADO.NET technology EditableThis DataList including ADO.NET internals, namespaces, classes, and


Table Applied ADO.NET—Building DataList Control Data-Driven footer Solutions Introduction Chapter 1 - ADO.NET Basics Chapter 2 - Data Components in Visual Studio .NET

' item here Environments Chapter 3 template - ADO.NET incode Disconnected Chapter 4 - ADO.NET in Connected Environments Chapter 5


Chapter 6 - Integrating XML with ADO.NET ' alternative itemand template codeData-Bound here Chapter 7 - Data Binding Windows Forms Controls - Constraints and Data Relations

Chapter 8 Chapter 9




Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 here - ASP.NET Server Controls and Data Binding ' code Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

If you run the application, the output looks like Figure 16-9.


Figure 16-9: EditableDataList control Now if you click an Edit link button, the item changes to editable form, which looks like Figure 16-10.


ISBN:1590590732


Figure 16-10: ADataList control in editable mode Table of Contents

The Update link button saves the changes, the Cancel link button ignores the changes and keeps the Applied ADO.NET—Building Data-Driven Solutions original values, and the Delete link button deletes the item. Introduction Chapter 1

- ADO.NET Basics

Using the VS .NET IDE to Set a DataList's Properties Chapter 2 - Data Components in Visual Studio .NET Chapter - ADO.NET in Disconnected Environments The VS3.NET IDE provides limited support to the DataList control. There are two common ways to set a Chapter 4 - control's ADO.NET properties. in Connected Environments DataList First, you can use the Properties windows; second, you can use the Chapter 5 Builder. - Handling Events Builder by right-clicking and selecting Property Builder or by Property YouADO.NET call the Property Chapter 6 Integrating XML with clicking the Property Builder link ADO.NET at the bottom of the Properties window, as shown in Figure 16-11. Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions IndexFigure 16-11: The Properties window of a DataList control List of Figures List of first Tables The page of the Property Builder is the General page. On this page, you can set DataKeyField and List of Listings other properties of the control. The Show Header and Show Footer check boxes indicate whether the List header of Sidebars and footer will be displayed in the control. In the Repeat Layout section, you can set the Columns,

Direction, and Layout properties. The second page of the Property Builder is the Format page. On this page, you can set the format of the control, header, footer, items, and separators. From this page, you can set the properties such as background color, foreground colors, font, and alignment of each portion of the DataList control. You can even set the format of items, alternating items, selecting items, and edit mode items from this page. The third page of the Property Builder is the Border Format page, which allows you to set the format of the DataList border. The properties on this page are cell padding, cell spacing, grid lines, border color, and border width.

Using the DataGrid WebBuilding Server ControlSolutions Applied ADO.NET: Data-Driven by Mahesh Chand and David Talbot

ISBN:1590590732

In Chapter 14, you learn about some DataGrid functionality. It discussed using data binding, setting a Apress © 2003 (928 pages) control's properties and styles using the Properties window as well as the Property Builder, writing event This text provides coveragecontrol. of ADO.NET technology handlers, and implementing pagingextensive in a DataGrid including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

TheDataGrid control's functionality doesn't end there; it provides much more than that. In this section, namespaces and classes, and how to integrate both with you'll see the restADO.NET. of the functionality. You'll work in the HTML View because it's easy to understand and modify. Table Caution of Contents If you skipped Chapter 14, you should go back and read the "DataGrid and DataList

Controls" section. Applied ADO.NET—Building Data-Driven Solutions Introduction

The following code creates a DataGrid control programmatically:

Chapter 1

- ADO.NET Basics

Chapter 2



Chapter 4 Chapter 5


Chapter 6


Chapter 7


Chapter - Constraints and Data Relations Similar8to the DataList control, the DataGrid control provides a DataSource property, which binds Chapter ADO.NET Exception Handling data to9the- control. Once you have set the DataSource property, you call the DataBind method. Listing Chapter 16-18 reads 10 - Working data from with the theCategories ODBC .NETtable Dataof Provider Northwind and binds the filled DataSet to the DataGrid Chapter control.11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Listing 16-18: Data Binding in a DataGrid Control



Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 -language="VB" Object-Relational Mapping in .NET Sub19Page_Load(sender As Object, e As EventArgs) Chapter - Mapped Objects: Performance Considerations and Data Binding If Not IsPostBack Then FillDataGrid() Chapter 21 - Messaging End If Chapter 22 - SQL Server and ADO.NET: Notes on Performance End SUb Appendix A - Relational Databases: Some Basic Concepts Sub FillDataGrid() Appendix B - Commonly Used SQL Statements Dim conn As SqlConnection Appendix C - ADO.NET Frequently Asked Questions Dim adapter As SqlDataAdapter Index dim connectionString = _ List of Figures "Data Source=MCB;Initial Catalog=Northwind;" & _ List of Tables "user id=sa;password=;" List of Listings conn = new SqlConnection(connectionString) List of Sidebars conn.Open() dim sql = "SELECT * FROM Categories" adapter = new SqlDataAdapter(sql, conn) Dim ds As Dataset = new DataSet() adapter.Fill(ds) dtGrid.DataSource = ds dtGrid.DataBind() End Sub Chapter 20 - COM Interoperability and ADO.NET

Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with The output of Listing 16-18 generates a page that looks like Figure 16-12. ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - 16-12: Stored Procedures and Figure Data binding in Views a DataGrid control Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

Setting Chapter 14 -DataGrid Developing Styles Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Besides setting a DataGrid control's properties at design-time, you can always set a DataGrid control's properties (including style properties) from the .aspx page by simply editing the HTML code using the VS Chapter 17 - Building Real-World Web Applications .NET IDE or a text editor. Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 18 - Object-Relational Mapping in .NET

TheDataGrid control provides properties that can set the its various parts. The DataGrid style Chapter 19 - Mapped Objects: Performance Considerations andstyle Dataof Binding properties AlternatingItemStyle, HeaderStyle,FooterStyle,EditItemStyle, Chapter 20 -are COM Interoperability and ADO.NET ItemStyle, and SelectedItemStyle, which represent styles for alternating items, headers, footers, Chapter 21 - Messaging edit items, and selected items, Notes respectively. Chapter 22 -items, SQL Server and ADO.NET: on Performance Appendix A - Relational Databases: Some Basic Concepts

Each of these style properties is a type of the TableItemStyle class, which inherits from the Style class. The TableItemStyle class represents the style of properties for an element of a control. Table Appendix C - ADO.NET Frequently Asked Questions 16-7 describes the TableItemStyle class properties. Appendix B - Commonly Used SQL Statements Index List of Figures Table 16-7: The TableItemStyle Class Properties List of Tables List of Listings List of Sidebars

PROPERTY


BackColor

by Mahesh Chand and David Talbot Background color of the item. Apress © 2003 (928 pages)

ISBN:1590590732

BorderColor This text Border providescolor extensive of thecoverage item. of ADO.NET technology including ADO.NET internals, namespaces, classes, and

BorderStyle interfaces,Border styleaof the item. It can beatDashed, Dotted,Double,Groove, and takes comprehensive look XML namespaces and None, classes, and howOutset, to integrate bothorwith Inset, Notset, Ridge, Solid. ADO.NET.

BorderWidth CssStyle Table of Contents

Width of the border. Cascading style of the item.

Applied FontADO.NET—Building Data-Driven FontInfo,Solutions which defines how the font will be displayed. Introduction

ForeColor Foreground color of the item. Chapter 1 - ADO.NET Basics Chapter 2 - Data Components in Visual Height Height of theStudio item. .NET Chapter 3


HorizontalAlign Horizontal alignment of the item. - ADO.NET in Connected Environments Chapter 5 - Handling ADO.NET Events VerticalAlign Vertical alignment of the item. Chapter 4 Chapter 6


Chapter 7


Chapter Wrap8

- Constraints and Data Relations If true, items will be wrapped; otherwise not. - ADO.NET Exception Handling

Width

Chapter 9

Width of the item.


Listing 11 16-19 adds Procedures some colors to Views the DataGrid control by setting its ItemStyle,HeaderStyle, Chapter - Stored and FooterStyle,AlternatingItemStyle, and EditItemStyle properties.


Listing 16-19: Setting a DataGrid Control's Style Properties



Figure 16-13 shows the new DataGrid control.


ISBN:1590590732



Figure 16-13: TheDataGrid control with the new styles

Chapter 1

- ADO.NET Basics

Chapter 2


Chapter Understanding 3 - ADO.NETainDataGrid's Disconnected Environments Columns Chapter 4


TheDataGrid control provides control and manages a DataGrid's columns in different ways. You can - Handling ADO.NET Events manage a DataGrid control's columns at design-time as well as at runtime. The Columns property of Chapter 6 - Integrating XML with ADO.NET theDataGrid control is the gateway to accessing and managing columns in a DataGrid at runtime. The Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Columns property represents a collection of DataGridColumn objects. Chapter 5

Chapter 8


Chapter 9 -AutoGenerateColumns ADO.NET Exception Handling Using the Property Chapter 10 - Working with the ODBC .NET Data Provider

So far you've seen Procedures that if you bind a DataGrid control to a data source, the control displays all the Chapter 11 - Stored and Views columns a data source in the same as they are defined in the data source. The Chapter 12available - Oracle, in SQLXML, and Other .NET Dataorder Providers

AutoGenerateColumns property controls this behavior of the DataGrid control. If you want to change the order of the columns, or you want to customize a DataGrid control, you must set the Chapter 14 - Developing Database Web Applications using ASP.NET AutoGenerateColumnsproperty to false. Chapter 13 - Developing a Custom Data Provider


Chapter 16setting - ASP.NET Server Controls and Data Bindingto true automatically binds columns for all fields in Actually, AutoGenerateColumns property Chapter 17 Building Real-World Web Applications the data source. Each field of the data source is rendered as a column of DataGrid. The BoundColumn Chapter 18 - Object-Relational Mapping .NET class represents a bound column of ainDataGrid control. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Using the Class Chapter 20 -DataGridColumn COM Interoperability and ADO.NET Chapter 21 - Messaging

TheDataGridColumn class represents a column of a DataGrid control. A DataGrid control can have different kind of columns such as bound columns, button columns, edit command columns, hyperlink Appendix A and - Relational Databases: Some Basic Concepts columns, button columns. The BoundColumn, ButtonColumn,EditCommandColumn, Appendix B - Commonly and UsedTemplateColumn SQL Statements HyperlinkColumn, classes represent the bound columns, button, edit Appendix C - hyperlink, ADO.NET Frequently Asked Questions command, and template column, respectively. The DataGridColumn class is the base class Index for all column classes. Chapter 22 - SQL Server and ADO.NET: Notes on Performance

List of Figures

The class provides properties that can format a DataGrid column's header and List ofDataGridColumn Tables

footers. These properties are FooterStyle,FooterText,HeaderImageUrl,HeaderStyle, and HeaderText. The ItemStyle property gets the style of a column's items. The SortExpression List of Sidebars property represents the name of the field or expressions, which are used in the OnSortCommand method when a column sorts its items. List of Listings

Customizing and Rearranging a DataGrid's Columns As you saw earlier, the DataGrid control generates a column for each column of a table in the data source in the same order as they're defined in the data source. But what if you don't want to display all the columns of a data source? One way to do this is to use a SELECT statement with the columns you want. There may be occasions when you want to control the column's display at runtime. For example, you may want to change the default order of the columns. To allow the custom view and selection of columns, the first thing you need to do is disable the

AutoGenerateColumns property:


AutoGenerateColumns=False

ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Now, because the AutoGenerateColumns property is false, you have to generate all the columns you interfaces, and takes a comprehensive look at XML want to display innamespaces a DataGrid control. You BoundColumn forwith adding data-bound columns to the and classes, anduse how to integrate both DataGrid control. You can use the Columnsproperty of DataGrid and bind the ADO.NET.

ASP:BoundColumn.DataField property to the data source. Listing 16-20 displays the Description, CategoryName, and CategoryID columns of the Categories table in the same order.

Table of Contents

Applied Data-Driven Solutions ListingADO.NET—Building 16-20: Rearranging a DataGrid Column's Sequence Introduction Chapter 1

- ADO.NET Basics Chapter 5 - Handling ADO.NET Events Chapter 6 - Integrating XML with ADO.NET Chapter Chapter 8 - Constraints and Data Relations Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

TheBoundColumn property provides the DataFormatString property, which can format the data of a column. You can even set the format of the BoundColumn header and footers. For this example, set the Chapter 15 - Using ADO.NET in Xml Web Services header and footer text for the columns by using the HeaderText and FooterText properties of Chapter 16 - ASP.NET Server Controls Binding BoundColumn. Listing 16-21 shows and the Data final code. Chapter 14 - Developing Database Web Applications using ASP.NET

Chapter 17 - Building Real-World Web Applications Chapter Listing18 16-21: - Object-Relational FormattingBoundColumn's Mapping in .NET Header and Footers Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Appendix List of Tables

Figure 16-14 shows the updated DataGrid control.


ISBN:1590590732



Figure 16-14: DataGrid with BoundColumns Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Calling DataGrid Events - ADO.NET in Disconnected Environments

Chapter 3

Chapter 4 - ADO.NET Connected Environments TheDataGrid eventsinplay a major role in DataGrid customization. In this section, you'll learn about the Chapter 5 Handling ADO.NET Events DataGrid events, which you'll use in later examples. Table 16-8 describes the DataGrid control events. Chapter 6


Chapter 7 - Data Binding and Control WindowsEvents Forms Data-Bound Controls Table 16-8: The DataGrid Chapter 8


EVENT - ADO.NET Exception DESCRIPTION Handling

Chapter 9

Chapter 10 - Working with theThe ODBC .NET button Data Provider CancelCommand Cancel tells a DataGrid control not to save the changes Chapter 11 - Stored Procedures and Views made to the items. This event occurs when a Cancel button in a Chapter 12 - Oracle, SQLXML,DataGrid and Other .NET Data Providers is clicked. The OnCancelCommand method raises this Chapter 13 - Developing a Custom event.Data TheProvider OnCancelCommand allows you to write a custom event

handler forApplications the CancelCommand, where you can get the data about a Chapter 14 - Developing Database Web using ASP.NET command. The CancelCommand event handler provides an argument Chapter 15 - Using ADO.NET in Xml Web Services DataGridCommandArgs, which gets the data associated with a Chapter 16 - ASP.NET Server of Controls and Data Binding command. Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-RelationalThe Mapping inbutton .NET deletes an item of a DataGrid control. This event DeleteCommand Delete Chapter 19 - Mapped Objects:occurs Performance Data Binding when aConsiderations Delete buttonand is clicked. The OnDeleteCommand Chapter 20 - COM Interoperability andraises ADO.NET method this event. The OnDeleteCommand allows you to write a Chapter 21 - Messaging custom event handler for the DeleteCommand, where you can get the Chapter 22 - SQL Server and data ADO.NET: aboutNotes a command. on Performance The DeleteCommand event handler provides

an argument of DataGridCommandArgs, which gets the data Appendix A - Relational Databases: Some Basic Concepts with a command. Appendix B - Commonly Usedassociated SQL Statements Appendix C - ADO.NET Frequently Asked Questions

EditCommand

Index List of Figures List of Tables List of Listings List of Sidebars

UpdateCommand

The Edit button edits a DataGrid control's items. This event occurs when the Edit button is clicked. The OnEditCommand method raises this event. The OnEditCommand allows you to write a custom event handler for the EditCommand, where you can get the data about a command. The EditCommand event handler provides an argument of DataGridCommandArgs, which gets the data associated with a command. The Update button saves the changes made to a DataGrid. This event occurs when the Update button is clicked. The OnUpdateCommand method raises this event. The OnUpdateCommandallows you to write a custom event handler for the UpdateCommand, where you can get the data about a command. The UpdateCommandevent handler provides an argument of DataGridCommandArgs, which gets the data associated with a command.

ItemCommand Applied ADO.NET: This eventBuilding occurs when any button on a DataGrid is clicked. The Data-Driven Solutions OnItemCommand method raises this event. Similar to previous event ISBN:1590590732 by Mahesh Chand and David Talbot handler, the OnItemCommand event also provides an argument of Apress © 2003 (928 pages) DataGridCommandArgs, which gets the data associated with a This text provides extensive coverage of ADO.NET technology command. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

ItemCreated namespaces This occurs items of thewith control are created. The andevent classes, and when how tothe integrate both ADO.NET. OnItemCreated method raises this event. This method also provides an argument of DataGridCommandArgs, which gets the data associated with a command.

Table of Contents

ItemDataBound This eventSolutions occurs when an item is bound to a DataGrid control. The Applied ADO.NET—Building Data-Driven OnItemDataBound method raises this event. The ItemDataBound event handler provides an argument of DataGridItemEventArgs, Chapter 1 - ADO.NET Basics which contains data related to this event. Chapter 2 - Data Components in Visual Studio .NET Chapter 3 - ADO.NET in Disconnected PageIndexChanged This eventEnvironments occurs when a paging selection of a DataGrid control is Chapter 4 - ADO.NET in Connected clicked.Environments Chapter 14 covers this event in it "Paging in the DataGrid Chapter 5 - Handling ADO.NET Control" Eventssection. Introduction

Chapter 6


Chapter 7


Chapter 8

-

Chapter 9

-

TheDataGrid control has default built-in functionality for sorting. By writing a few lines of code, you can add the sorting functionality to a Constraints and DataGrid Data Relations control. First of all, you need to set the AllowSorting ADO.NET Exception Handling property of the DataGrid to true. Second of all, you need to write a Working with theSortCommand ODBC .NET Data Provider event handler. The SortCommand event handler Stored Procedures and Views provides an argument of DataGridSortCommandEventArgs, which Oracle, SQLXML,returns and Other DatatoProviders data.NET related the sort command such as the column being Developing a Custom Provider used Data to sort the data.

SortCommand

Chapter 10 Chapter 11 Chapter 12 Chapter 13 -


Using16the DataGridCommandEventArgs Chapter - ASP.NET Server Controls and Data Binding

Class


This class provides data for the CancelCommand,DeleteCommand,EditCommand,ItemComand, and UpdateCommand events. The event handler of these events takes an argument of Chapter 19 - Mapped Objects: Performance Considerations and Data Binding DataGridCommandEventArgs, which can be used to get the data about a command. Chapter 18 - Object-Relational Mapping in .NET


Chapter 21 - Messaging TheCommandArgument property returns an argument for the command. The CommandName property Chapter returns22 thename SQL Server of theand command, ADO.NET: which Notescan on be Performance set by using a column's CommandName property. The

CommandSource property returns the source of the command, and the Item property returns the item of Appendix A - Relational Databases: Some Basic Concepts theDataGrid that contains the command. Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Using Index

a DataGrid Control with Button Columns

List of Figures

TheButtonColumn class represents a button column. A button column can have two types: a push button or a link button. The ButtonType property of ButtonColumn represents the type of button.

List of Tables

List of Listings

List The ofCommandName Sidebars property is a string that represents the command to perform when the button is

clicked. It's used to handle the button click event handler. The DataGridCommandEventArgs's CommandName property returns the CommandName of a column. TheDataTextField property binds a data source field to a button column, and DataTextFormatString represents the format of the column, which will be displayed in a DataGrid. TheText property represents the text of a column. The following code creates two button columns: ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) namespaces and classes, and how to integrate both with ADO.NET. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

The next step is to handle the button click event. The following code adds an ItemCommand event Introduction handler1 to-aADO.NET DataGrid control: Chapter Basics Chapter 2


Chapter Chapter 4


Chapter 5


Now you'll change the format of the row clicked in a DataGrid control. Listing 16-22 shows the event - Integrating XML with ADO.NET handler of the button click. As you can see from this listing, you find out what command name was clicked Chapter 7 - Data Binding and Windows Forms Data-Bound Controls and set the row's format accordingly. Chapter 6 Chapter 8


Chapter - ADO.NET Exception Handling Listing916-22: The ButtonColumn Click Event Handler Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

Sub dtGridItem(obj as Object, args as DataGridCommandEventArgs) If (args.CommandName = "Yes") Then Chapter 13 - Developing a Custom Data Provider args.Item.BackColor = System.Drawing.Color.Gray Chapterargs.Item.ForeColor 14 - Developing Database Web Applications using ASP.NET = System.Drawing.Color.White Chapterargs.Item.Font.Name 15 - Using ADO.NET in Xml = Web Services "tahoma" Chapter 16 ASP.NET Server Controls and Data Binding Else Chapterargs.Item.BackColor 17 - Building Real-World Web Applications = System.Drawing.Color.Black Chapterargs.Item.ForeColor 18 - Object-Relational Mapping in .NET = System.Drawing.Color.LightSteelBlue Chapterargs.Item.Font.Name 19 - Mapped Objects: Performance = "verdana" Considerations and Data Binding End If Chapter 20 - COM Interoperability and ADO.NET End Sub Chapter 21 - Messaging Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


This DataGrid control looks like Figure 16-15 with the button columns. When you click the Select or UnSelect link button, you see the changes in the selected row.


List of Figures List of Tables List of Listings List of Sidebars

Figure 16-15: ADataGrid control with button columns

Listing 16-23 shows the complete code.


by Maheshwith Chand and David Talbot Listing 16-23: DataGrid Button Columns

ISBN:1590590732

Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET. Sub Page_Load(sender As Object, e As EventArgs) If Not IsPostBack Then Table of Contents FillDataGrid() Applied ADO.NET—Building Data-Driven Solutions End If Introduction End SUb Chapter 1

- ADO.NET Basics

Chapter - Data Components in Visual Studio .NET Sub2 FillDataGrid() Chapter 3 conn - ADO.NET in Disconnected Environments Dim As SqlConnection Chapter 4 Dim - ADO.NET in Connected Environments adapter As SqlDataAdapter Chapter 5 dim - Handling ADO.NET Events = _ connectionString Chapter 6 "Data - Integrating Source=MCB;Initial XML with ADO.NET Catalog=Northwind;" & _ Chapter 7 "user - Data id=sa;password=;" Binding and Windows Forms Data-Bound Controls

= new and SqlConnection(connectionString) Chapter 8 conn - Constraints Data Relations Chapter 9 conn.Open() - ADO.NET Exception Handling

dim sql =with "SELECT * .NET FROM Categories" Chapter 10 - Working the ODBC Data Provider adapter = new SqlDataAdapter(sql, conn) Chapter 11 - Stored Procedures and Views Dim ds As Dataset = new DataSet() adapter.Fill(ds) Chapter 13 - Developing a Custom Data Provider dtGrid.DataSource = ds Chapter 14 - Developing Database Web Applications using ASP.NET dtGrid.DataBind() Chapter 15 - Using ADO.NET in Xml Web Services End Sub Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


Chapter - Building Real-World Applications Sub17dtGridItem(obj asWeb Object, args as DataGridCommandEventArgs) ChapterIf 18 (args.CommandName - Object-Relational Mapping .NET = in "Yes") Then Chapter 19 - Mapped Objects: Performance Considerations and Data Binding args.Item.BackColor = System.Drawing.Color.Gray Chapter 20 - COM Interoperability and = ADO.NET args.Item.ForeColor System.Drawing.Color.White Chapter 21 - Messaging args.Item.Font.Name = "tahoma" ChapterElse 22 - SQL Server and ADO.NET: Notes on Performance

args.Item.BackColor = System.Drawing.Color.Black Appendix A - Relational Databases: Some Basic Concepts args.Item.ForeColor = System.Drawing.Color.LightSteelBlue Appendix B - Commonly Used SQL Statements args.Item.Font.Name = Questions "verdana" Appendix C - ADO.NET Frequently Asked End If Index End Sub List of Figures List of Listings List of Sidebars List of Tables

Applied ADO.NET: Building Data-Driven Solutions including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1 - ADO.NET Basics Chapter 2 - Data Components in Visual Studio .NET Chapter 3 - ADO.NET in Disconnected Environments Chapter 4


Chapter 5


Chapter 6


Using7 a -DataGrid with Template Columns Chapter Data BindingControl and Windows Forms Data-Bound Controls Chapter 8


Templates are one of the ways to customize DataGrid columns. The TemplateColumn class - ADO.NET Exception Handling represents a template column in a DataGrid control. A template column allows you to customize a Chapter 10 - Working with the ODBC .NET Data Provider column's layout. Chapter 9


Chapter Similar12 to other - Oracle, column SQLXML, classes, and Other this class .NETalso Datainherits Providers from the DataGridColumn class. Besides the

functionality provided by Chapter 13 - Developing a DataGridColumn, Custom Data Providerthis class provides properties to set the layout of header, footer, 14 item, and edit items of theWeb control. The HeaderTemplate, FooterTemplate.ItemTemplate, Chapter - Developing Database Applications using ASP.NET andEditItemTemplate the custom appearance of the header, footer, items, and Chapter 15 - Using ADO.NET properties in Xml Webprovide Services items that being edited Chapter 16 -are ASP.NET Server (respectively). Controls and Data Binding Chapter 17 - Building Real-World Web Applications

For example, Listing 16-24 creates a TemplateColumn and sets its ItemTemplate, HeaderTemplate, and FooterTemplates properties.


Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter - COMUsing Interoperability ADO.NET Listing20 16-24: Templateand Columns Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index

List of Figures List of TablesCategory ID:

List of Listings List of Sidebars Category Name: Description: DataGrid with Template Columns

Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) DataGrid Footer This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Table of Contents Figure 16-16 shows the result of using template columns. Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure 16-16: Using template columns

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter - Using ADO.NET in Xml Web Services Listing 15 16-25 shows the complete code. Chapter 16 - ASP.NET Server Controls and Data Binding

Listing17 16-25: Using Template Columns in a DataGrid Control Chapter - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter and Data Binding

Chapter 20 - COMNamespace="System.Data.SqlClient" Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Sub APage_Load(sender Object, e As EventArgs) Appendix - Relational Databases:As Some Basic Concepts IfB Not IsPostBack Then Appendix - Commonly Used SQL Statements FillDataGrid() End If Index End SUb

Appendix C - ADO.NET Frequently Asked Questions List of Figures List of Tables

Sub FillDataGrid() Dim conn As SqlConnection List of Sidebars Dim adapter As SqlDataAdapter dim connectionString = _ "Data Source=MCB;Initial Catalog=Northwind;" & _ "user id=sa;password=;" conn = new SqlConnection(connectionString) conn.Open() dim sql = "SELECT * FROM Categories" adapter = new SqlDataAdapter(sql, conn) Dim ds As Dataset = new DataSet() adapter.Fill(ds) dtGrid.DataSource = ds dtGrid.DataBind() List of Listings

End Sub Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology Chapter 5 - Handling ADO.NET Events Chapter 6


Chapter 7


Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider Category ID: Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - DevelopingCategory a Custom Data Provider Name: Chapter 14 - Developing Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Description: Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance DataGrid Columns Appendix A - Relational Databases:with Some Template Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index DataGrid Footer List of Figures List of Tables List of Listings List of Sidebars Chapter 8


Creating an Editable DataGrid Writing an editable DataGrid is one more useful feature of a DataGrid control. You allow users to add, delete, edit, and save changes through a DataGrid control. Adding data to a DataGrid is pretty simple; you don't need to use any special code. You simply use some TextBox controls to get input from the

user, construct a SQL statement, execute the SQL statement, and refill the DataGrid control. When you Applied ADO.NET: Building Data-Driven Solutions need to delete some data, you can simply find out the primary key of the row you want to delete, construct ISBN:1590590732 Maheshthe Chand and David a SQL statement,byexecute statement, andTalbot refill the DataGrid. Apress © 2003 (928 pages)

Editing, in other words, is no more extensive difficult than addingofand deleting the data. Unlike the Windows Forms This text provides coverage ADO.NET technology including ADO.NETDataGrid internals, namespaces, classes, DataGrid control, the ASP.NET control doesn't have and an edit mode. To make an ASP.NET interfaces, at XML DataGrid control editable,and youtakes needatocomprehensive add TextBoxlook controls and place them as the DataGrid items. namespaces and classes, and how to integrate both with Once the user is ADO.NET. done editing, you need to provide a mechanism to read the data from the TextBox controls and then construct an UPDATE SQL statement, execute it, and refill the DataGrid with new data. So, the first thing you need to do is to provide some buttons for the DataGrid control, which can set a Table of Contents DataGrid in editable mode. You canSolutions do this with the help of EditCommand columns. The Applied ADO.NET—Building Data-Driven

EditCommand column adds an Edit button to the DataGrid control. When you click the Edit button, it changes the control's current cells into TextBox controls and provides Update and Cancel buttons.


- ADO.NET Basics

Chapter 2 - Data Componentsclass in Visual Studio .NET TheEditCommandColumn represents an EditCommand column. This class provides properties Chapter 3 ButtonType, - ADO.NET in Disconnected Environments including CancelText, EditText, and UpdateText. The ButtonType property Chapter 4 - whether ADO.NETthe in Connected represents buttons areEnvironments hyperlink buttons or push buttons. The CancelText,EditText, and Chapter 5 - Handling ADO.NET Events UpdateText properties represent the text of the Cancel, Edit, and Update buttons. For example, the Chapter following 6 code - Integrating sets the XML EditCommandColumn with ADO.NET properties: Chapter 7


Chapter 8 - Constraints and Data Relations Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET TheDataGrid control with an EditCommandColumn looks like Figure 16-17. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 16-17: DataGrid with EditCommandColumn If you click the Edit button, the current row of the DataGrid will have TextBoxcontrols and the Edit button will be replaced with Save and Cancel buttons, as shown in Figure 16-18.


ISBN:1590590732



- ADO.NET Basics

Figure DataGridinwith Save and .NET Cancel options Chapter 2 - 16-18: Data Components Visual Studio Chapter 3


Chapter 4 You - ADO.NET in Connected Note can change the textEnvironments of the Update and Cancel buttons by setting the EditText, Chapter 5 UpdateText, - Handling ADO.NET Events and CancelText properties. Chapter 6

- Integrating XML with ADO.NET After setting the EditCommandColumn properties, you need to write the button click event handlers. The Chapter 7 - Data Binding and Windows Forms Data-Bound Controls

OnCancelCommand, OnUpdateCommand, Chapter 8 - Constraints and Data Relations and OnEditCommand methods of the DataGrid control are responsible for raisingException the Cancel, Update, and Edit button click events, respectively. The following code Chapter 9 - ADO.NET Handling adds event for these commands: Chapter 10 - handlers Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

OnCancelCommand="dtGridCancel" Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers OnUpdateCommand="dtGridUpdate" Chapter 13 - Developing a Custom Data Provider OnEditCommand="dtGridEdit" Chapter 14 - Developing Database Web Applications using ASP.NET DataKeyField="CategoryID" Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17need - Building Real-World Applications Now you to write the codeWeb for these command handlers. Editing in a DataGrid control works in a Chapter Object-Relational .NET 16-26 shows the complete code of an editable DataGrid. similar 18 way- to the DataListMapping control.inListing Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Listing20 16-26: DataGrid Chapter - COMEditable Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQLNamespace="System.Data.SqlClient" Server and ADO.NET: Notes on Performance Appendix A Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index Editable DataGrid Sample

List of Figures Shared ConnectionString As String = "user id=sa;password=;" & _ List of Tables "Initial Catalog=Northwind;" & _ List of Listings "Data Source=MCB;" List of Sidebars Shared Shared Shared Shared Shared

conn As SqlConnection = Nothing adapter As SqlDataAdapter = Nothing sql As String = Nothing cmd as SqlCommand = Nothing ds as DataSet = Nothing

Private Sub Page_Load(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles MyBase.Load 'Put user code to initialize the page here If Not IsPostBack Then FillDataGrid() End If

End Sub Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot ' FillDataGrid method Apress © 2003 (928 pages) Private Sub FillDataGrid() ThisSqlConnection(ConnectionString) text provides extensive coverage of ADO.NET technology conn = New including ADO.NET internals, namespaces, classes, If conn.State ConnectionState.Closed Thenand interfaces, and takes a comprehensive look at XML conn.Open() namespaces and classes, and how to integrate both with End If ADO.NET. sql = "SELECT * FROM Categories" ds = New DataSet() Table ofadapter Contents = New SqlDataAdapter(sql, conn) Appliedadapter.Fill(ds) ADO.NET—Building Data-Driven Solutions Introduction dtGrid.DataSource = ds.Tables(0) ChapterdtGrid.DataBind() 1 - ADO.NET Basics ChapterIf 2 conn.State - Data Components = ConnectionState.Open in Visual Studio .NET Then Chapter 3 conn.Close() - ADO.NET in Disconnected Environments ChapterEnd 4 -If ADO.NET in Connected Environments End5 Sub Chapter - Handling ADO.NET Events ' EditCommand handler Chapter 6 - Integratingevent XML with ADO.NET Sub7 dtGridEdit(obj as Object, as DataGridCommandEventArgs) Chapter - Data Binding and Windows Forms args Data-Bound Controls dtGrid.EditItemIndex = args.Item.ItemIndex Chapter 8 - Constraints and Data Relations FillDataGrid() Chapter 9 - ADO.NET Exception Handling End Sub Chapter 10 - Working with the ODBC .NET Data Provider ' UpdateCommand Event handler Chapter 11 - Stored Procedures and Views Sub dtGridUpdate(obj as Object, args as DataGridCommandEventArgs) Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Dim catId as Integer ChapterDim 13 -strName Developingas a Custom Data Provider String ChapterDim 14 -strDes Developing Database Web Applications using ASP.NET as String ChapterDim 15 -catNameTextBox Using ADO.NET in Xml Web Services as TextBox ChapterDim 16 -desTextBox ASP.NET Serveras Controls and TextBoxData Binding Chapter'17 Building Real-World Web Applications Read text from text boxes ChaptercatId 18 - Object-Relational = dtGrid.DataKeys(args.Item.ItemIndex) Mapping in .NET = Performance args.Item.Cells(1).Controls(0) ChaptercatNameTextBox 19 - Mapped Objects: Considerations and Data Binding = args.Item.Cells(2).Controls(0) ChapterdesTextBox 20 - COM Interoperability and ADO.NET = catNameTextBox.Text ChapterstrName 21 - Messaging desTextBox.Text ChapterstrDes 22 - SQL=Server and ADO.NET: Notes on Performance ' AConstruct an UPDATE SQL statement Appendix - Relational Databases: Some Basic Concepts sql = "UPDATE Categories SET CategoryName=@catName, " & _ Appendix B - Commonly Used SQL Statements " Description=@desc WHERE CategoryID=@id" Appendix C - ADO.NET Frequently Asked Questions ' Construct a SqlCommand Index cmd = new SqlCommand(sql, conn) List of Figures ' Add parameters to the command with the values List of Tables ' read from text boxes and category ID List of Listings cmd.Parameters.Add("@id", catId) List of Sidebars cmd.Parameters.Add("@catName", strName) cmd.Parameters.Add("@desc", strDes) ' Open the connection conn.Open() ' Execute SQL statement cmd.ExecuteNonQuery() ' Close the connection conn.Close() ' Close editing mode of DataGrid dtGrid.EditItemIndex = -1 ' Refill DataGrid with the updated data FillDataGrid()

End Sub Applied ADO.NET: Building Data-Driven Solutions ' CancelCommand Event ISBN:1590590732 by Mahesh Chandhandler and David Talbot Sub dtGridCancel(obj aspages) Object, args as DataGridCommandEventArgs) Apress © 2003 (928 dtGrid.EditItemIndex = -1 This text provides extensive coverage of ADO.NET technology FillDataGrid() including ADO.NET internals, namespaces, classes, and End Sub interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ' Sort Event handler ADO.NET. Sub dtGridSort(obj as Object, args as DataGridSortCommandEventArgs) Dim sortExpr as String ' Open the connection Table of Contents If conn.State ConnectionState.Closed Then Applied ADO.NET—Building Data-Driven Solutions conn.Open() Introduction End If Chapter 1 - ADO.NET Basics ' Get the column from SortCommand Event Args Chapter 2 - Data Components in Visual Studio .NET sortExpr = args.SortExpression Chapter 3 - ADO.NET in Disconnected Environments ' Create a SELECT Statement with ORDER BY the expression Chaptersql 4 -=ADO.NET in Connected "SELECT * FROM Environments Categories ORDER BY " + sortExpr Chapterds 5 =- Handling ADO.NET New DataSet()Events Chapteradapter 6 - Integrating with ADO.NET = NewXML SqlDataAdapter(sql, conn) Chapteradapter.Fill(ds) 7 - Data Binding and Windows Forms Data-Bound Controls ChapterdtGrid.DataSource 8 - Constraints and Data = Relations ds.Tables(0) ChapterdtGrid.DataBind() 9 - ADO.NET Exception Handling Then ChapterIf 10 conn.State - Working with = theConnectionState.Open ODBC .NET Data Provider conn.Close() Chapter 11 - Stored Procedures and Views ChapterEnd 12 -If Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

End14Sub Chapter - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Editable DataGrid Sample Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter Chapter 21 Messaging Chapter 16 - ASP.NET Server Controls and Data Binding

Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML ADO.NET.

Table of Contents Applied ADO.NET—Building Data-Driven Solutions Chapter 1

- ADO.NET Basics

Chapter 2

- Data - ADO.NET in Disconnected Environments

Chapter 4


Chapter 5

Chapter 7


Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 ASP.NET Server Controls and Data Binding Chapter 17 Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 8



Sorting Searching inStatements a DataGrid Appendix B -and Commonly Used SQL Appendix C - ADO.NET Frequently Asked Questions

TheDataGrid control provides partial built-in support for sorting. The AllowSorting property's true value makes DataGrid columns link buttons, which can sort a column's values. The OnSortCommand List of Figures method raises the sort event of the control. The following code activates the sorting in a DataGrid: Index


List of Sidebars

TheOnSortCommand handler provides sorting data as the name of the column by using DataGridSortCommandEventArgs.SortExpression, as shown in the following code: ' Sort Event handler Sub dtGridSort(obj as Object, args as DataGridSortCommandEventArgs) Dim sortExpr as String

sortExpr = args.SortExpression Applied ADO.NET: Building Data-Driven Solutions FillDataGrid(sortExpr) ISBN:1590590732 by Mahesh Chand and David Talbot End Sub Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes comprehensive Note The default sorting order is aascending. If youlook wantattoXML provide descending order, you need to namespaces and classes, and how to integrate both with construct an ORDER BY query with a DESCENDING option. ADO.NET.

Once you know the column, you can simply construct an ORDER BY query and refill the data in the control. Listing 16-27 shows the complete code for sorting in a DataGrid control. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Listing 16-27: Implementing Sorting in a DataGrid Control


- ADO.NET Basics

Chapter 2 - Data Components in Visual Studio .NET Chapter 3 - ADO.NET in Disconnected Environments Chapter 4 - ADO.NET in Connected Environments Chapter 5 - Handling ADO.NET Events Editable DataGrid Sample Chapter 6 - Integrating XML with ADO.NET Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Shared ConnectionString As String = "user id=sa;password=;" & _ Chapter 8 - Constraints and Data Relations "Initial Catalog=Northwind;" & _ Chapter 9 - ADO.NET Exception Handling "Data Source=MCB;" Chapter 10 - Working withSqlConnection the ODBC .NET Data Shared conn As = Provider Nothing Chapter 11 Stored Procedures and Views Shared adapter As SqlDataAdapter = Nothing Chapter 12 - Oracle, SQLXML, and =Other .NET Data Providers Shared sql As String Nothing Chapter 13 - Developing a Custom Data = Provider Shared cmd as SqlCommand Nothing Chapter 14 - Developing Database =Web Applications using ASP.NET Shared ds as DataSet Nothing Chapter 15 - Using ADO.NET in Xml Web Services

Private Sub Page_Load(ByVal sender As System.Object, _ Chapter 16 - ASP.NET Server Controls and Data Binding ByVal As System.EventArgs) Handles MyBase.Load Chapter 17 -eBuilding Real-World Web Applications user code toMapping initialize Chapter'Put 18 - Object-Relational in .NET the page here IsPostBack Then ChapterIf 19 Not - Mapped Objects: Performance Considerations and Data Binding Chapter FillDataGrid("") 20 - COM Interoperability and ADO.NET

End If End Sub


' FillDataGrid method Private Sub FillDataGrid(str as String) Appendix C - ADO.NET Frequently Asked Questions conn = New SqlConnection(ConnectionString) Index If conn.State ConnectionState.Closed Then List of Figures conn.Open() List of Tables End If List of Listings if str = "" Then List of Sidebarssql = "SELECT * FROM Categories" Else sql = "SELECT * FROM Categories ORDER BY " + str End If ds = New DataSet() adapter = New SqlDataAdapter(sql, conn) adapter.Fill(ds) dtGrid.DataSource = ds.Tables(0) dtGrid.DataBind() If conn.State = ConnectionState.Open Then conn.Close() End If Appendix B - Commonly Used SQL Statements

End Sub Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot ' Sort Event handler Apress © 2003 (928 pages) Sub dtGridSort(obj as Object, args as DataGridSortCommandEventArgs) This text extensive coverage of ADO.NET technology Dim sortExpr asprovides String including ADO.NET internals, namespaces, classes, and sortExpr = args.SortExpression interfaces, and takes a comprehensive look at XML FillDataGrid(sortExpr) namespaces and classes, and how to integrate both with End Sub ADO.NET.

Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Sorting in DataGrid Chapter 1 - ADO.NET Basics Chapter Studio .NET

id="dtGrid" Chapter 3 - Integrating XML with ADO.NET Chapter 7 - Data Binding and Windows Forms Data-Bound Controls


Chapter 8 Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, andtext, Other .NET Data Providers Caution You can't use the ntext, and image data types in an ORDER BY clause. Chapter 13 - Developing a Custom Data Provider

To implement searching in a DataGrid control, you to read the name of the column and a value for Chapter 14 - Developing Database Web Applications usingneed ASP.NET which you're searching. After that Web you can simply construct a SELECT..WHERE clause and refill the data. Chapter 15 - Using ADO.NET in Xml Services If you don't to sort andControls read data from data source, you can simply create a DataView control Chapter 16 - want ASP.NET Server and Dataa Binding from a 17 data source using a DataSet, apply sort and filter criteria on a DataView, and bind the Chapter - Building Real-World Web Applications DataView the DataGridMapping control.in(See Chapter 18 - to Object-Relational .NETthe DataGrid and "Implementing Search in a DataGrid" sections 7 for more information.) Sorting andand searching works in both the controls in the same Chapter 19of- Chapter Mapped Objects: Performance Considerations Data Binding way because it's done through ADO.NET. The only difference is the data binding.



Summary


ISBN:1590590732

Even though the Apress data-binding concept © 2003 (928 pages)in ASP.NET server controls looks similar to Windows Forms data binding, they workThis in totally different ways. Incoverage this chapter, you learned the basic concepts of data binding text provides extensive of ADO.NET technology in ASP.NET server controls and how to implement data binding in simple and complex data-bound including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML controls. namespaces and classes, and how to integrate both with ADO.NET. Templates and columns play a major role in the formatting and data binding of controls. This chapter

discussed how templates and columns work in ASP.NET. We also discussed the various functionality of theDataList and DataGrid ASP.NET server controls.

Table of Contents

Applied ADO.NET—Building Solutionsdata-driven Web application using ASP.NET. You'll use the In the next chapter, you'llData-Driven create a real-world Introduction major data-binding concepts discussed in this chapter. Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 17: Building Real-WorldISBN:1590590732 Web Applications by Mahesh Chand and David Talbot Apressthe © 2003 (928of pages) Chapter 14 discussed basics ASP.NET and how to write data-driven Web applications using This text provides coverage ADO.NET technology ASP.NET and ADO.NET. Chapter extensive 16 discussed data of binding in ASP.NET and ASP.NET server controls including ADO.NET internals, namespaces, classes, and and how to use these controls to develop data-bound Web applications. interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with In this chapter, we'll use the functionality discussed in Chapter 14 and 16. In this chapter, you'll see how ADO.NET.

you can write a real-world online job board where candidates can post their resumes, recruiters can post their jobs, recruiters can browse the available resumes, and job hunters can browse and apply for the Table of Contents available jobs on the site. Applied ADO.NET—Building Data-Driven Solutions

Introducing the Job Board Application Specifications


- ADO.NET Basics

Chapter The Online 2 - Job DataBoard Components is an ASP.NET in Visual Studio application .NET that allows users to post their resumes. Interface-wise,

the application has three main modules: login, resumes, and jobs. The login module is a simple page that Chapter 3 - ADO.NET in Disconnected Environments allows users to log in in toConnected the site. The resumes module allows users to post their resumes and view all the Chapter 4 - ADO.NET Environments available in ADO.NET the database. Chapter 5 resumes - Handling EventsThe jobs module allows users to post their jobs on the site and view all the available jobs in theXML database. Chapter 6 - Integrating with ADO.NET Chapter 7


Figure 17-1 describes the application architecture. As you can see from Figure 17-1, the first page the user Chapter 8 - Constraints and Data Relations goes to is the login page. From there, the user either can log in to the site or can register if they aren't Chapter - ADO.NET user. Exception already9a registered OnceHandling user is logged in, there are four options: Post Jobs, Post Resumes, View Chapter 10 Working with the Jobs, and View Resumes. ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 17-1: The Online Job Board application architecture

Appliedthe ADO.NET: Building Schema Data-Driven Solutions Understanding Database by Mahesh Chand and David Talbot

ISBN:1590590732

For this application, we're using a pages) SQL Server database to store the user, resume, and job-related Apress © 2003 (928 information. To keep the application simple, coverage we've used only threetechnology tables: Job, Resumes, and Users. The This text provides extensive of ADO.NET Job table has six including columns ADO.NET (see Figure 17-2). internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2 - 17-2: Data Components in Visual Studio .NET Figure Schema of the Job table Chapter 3 - ADO.NET in Disconnected Environments Chapter 4


Figure 17-3 shows the Resumes table schema, which has 10 columns. These columns store the - Handling ADO.NET Events information about a candidate including a detailed resume.

Chapter 5 Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure 17-3: Schema of the Resumes table


Chapter - Object-Relational in .NET which has only three columns to store the user ID, password, Figure 18 17-4 shows the UsersMapping table schema, Chapter 19 -address. Mapped Objects: Performance Considerations and Data Binding and email Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index

Figure 17-4: Schema of the Users table



ADO.NET:Job Building Data-Driven Solutions DevelopingApplied the Online Board Application by Mahesh Chand and David Talbot

ISBN:1590590732

When you start the application, thepages) first page is Login.aspx. When you create an ASP.NET Web Apress © 2003 (928 application, it adds WebForm1 as the first page of the of application. You can simply change the name of this This text provides extensive coverage ADO.NET technology page to Login.aspx. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Creating the Login.aspx Page

TheLogin.aspx page allows users to enter their user ID and password and checks these against the Table Contents dataof stored in the database. If the user ID and password are found in the database table, then you let them Applied Solutions see theADO.NET—Building available options.Data-Driven Otherwise they need to register as a new user. Introduction

TheLogin.aspx page looks like Figure 17-5. As you can see from this page, it has two TextBox - ADO.NET Basics controls, one Hyperlink control, five Button controls, two Label controls, and a StatusBar control. Chapter 2 - Data Components in Visual Studio .NET When a user comes to this page, the buttons (Post a New Job, Post a New Resume, View Jobs, and View Chapter 3 - ADO.NET in Disconnected Environments Available Resumes) are hidden. These buttons are visible when user successfully logs in to the site. Chapter 1

Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Figure TheFrequently Login.aspx page Appendix C - 17-5: ADO.NET Asked Questions Index

Listing 17-1 shows the code for the Login button click event handler. Here you simply read the values entered in the User ID and Password TextBox controls and check if these values exist in the database. List of Tables As you can see from this code, you create and open a connection, read UserID and Password from the List of Listings Users table by creating a SqlCommand object, and call its ExecuteReader method that creates a List of Sidebars SqlDataReader. You use only a single row because a single row will tell you whether the user exists in the table. After, that if the user exists, you display the Post a New Job, Post a New Resume, View Jobs, and View Available Resumes buttons and hide the TextBox,Label, and Hyperlink controls. You also display a message in the StatusBar control, if the user is logged in or not. List of Figures

Listing 17-1: Login Button Click Event Handler Code Private Sub LoginBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles LoginBtn.Click ' Create and open a connection conn = New SqlConnection(connectionString)

If (conn.State ConnectionState.Open) Then Applied ADO.NET: Building Data-Driven Solutions conn.Open() ISBN:1590590732 End If by Mahesh Chand and David Talbot Apress © 2003 (928 pages) ' Construct a SQL string This text provides of ADO.NET technology sql = "SELECT * FROMextensive Users coverage WHERE UserID='" + _ including ADO.NET internals, namespaces, classes, and IdTextBox.Text + _ interfaces, and takes a comprehensive look at XML "' AND Password '" +and PassTextBox.Text "'" namespaces and = classes, how to integrate both + with ' and fill it ADO.NET. Dim reader As SqlDataReader Dim cmd As SqlCommand = New SqlCommand(sql) Table of cmd.Connection Contents = conn Applied ADO.NET—Building Data-Driven Solutions reader = cmd.ExecuteReader(CommandBehavior.SingleRow) Introduction If (reader.Read()) Then Chapter 1 - ADO.NET Basics PostJobBtn.Visible = True Chapter 2 - Data PostResumeBtn.Visible Components in Visual Studio = .NET True ViewJobsBtn.Visible = True Chapter 3 - ADO.NET in Disconnected Environments ViewResumesBtn.Visible = True Chapter 4 - ADO.NET in Connected Environments StatusBar.Text = "Logged In" Chapter 5 - Handling ADO.NET Events Label1.Visible = False Chapter 6 - Integrating XML with ADO.NET Label2.Visible = False Chapter 7 - Data Binding and Windows Forms Data-Bound Controls IdTextBox.Visible = False Chapter 8 - Constraints and Data Relations PassTextBox.Visible = False Chapter 9 - ADO.NET Exception Handling NewUserLink.Visible = False Chapter 10 - Working with the ODBC .NET Data Provider LoginBtn.Visible = False Chapter 11 - Stored Procedures and Views Else Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers StatusBar.Text = _ Chapter 13 - Developing a Custom Data Provider "Enter a valid User ID and Password!" Chapter End 14 - Developing Database Web Applications using ASP.NET If Chapter ' 15 Close - Using ADO.NET in Xml Web Services the connection Chapter If 16 -(conn.State ASP.NET Server Controls and Data Binding = ConnectionState.Open) Then Chapter 17 - Building Real-World Web Applications conn.Close() Chapter End 18 - Object-Relational If Mapping in .NET End Sub Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

When you click the New User? Register Here HyperLink control, it simply opens the Register.aspx page. You do this by setting the NavigateUrl property of the HyperLink control as shown in Figure 17Appendix B - Commonly Used SQL Statements 6. Appendix A - Relational Databases: Some Basic Concepts Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 17-6: Setting the NavigateUrl property of a HyperLink control The Post a New Job, Post a New Resume, View Available Resumes, and View Jobs button clicks simply open new Web pages: PostJob.aspx,PostResume.aspx,DisplayData.aspx, and

Resumes.aspx, respectively (we'll discuss them in a moment). Listing 17-2 shows the code for these ADO.NET: Building Data-Driven button click eventApplied handlers. As you can see, the code uses Solutions the Me.Response.Redirect method to ISBN:1590590732 by Mahesh Chand and David Talbot open the new Web pages. Apress © 2003 (928 pages)

Listing 17-2: TheThis Button text provides Click Event extensive Handlers coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Private Sub PostResumeBtn_Click(ByVal As System.Object, _ namespaces and classes, and how to sender integrate both with ByVal e AsADO.NET. System.EventArgs) Handles PostResumeBtn.Click

Me.Response.Redirect("PostResume.aspx") End Sub


Private Sub ViewJobsBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles ViewJobsBtn.Click Chapter 1 -Me.Response.Redirect("DisplayData.aspx") ADO.NET Basics Chapter 2 - Data Components in Visual Studio .NET End Sub Chapter 3 -Sub ADO.NET in Disconnected Environments Private PostJobBtn_Click(ByVal sender As System.Object, _ ChapterByVal 4 - ADO.NET in Connected Environments e As System.EventArgs) Handles PostJobBtn.Click Chapter 5 -Me.Response.Redirect("PostJob.aspx") Handling ADO.NET Events Chapter End Sub 6 - Integrating XML with ADO.NET Introduction

Chapter 7


Private ViewResumesBtn_Click(ByVal sender As System.Object, _ Chapter 8 -Sub Constraints and Data Relations ByVal e As System.EventArgs) Handles ViewResumesBtn.Click Chapter 9 - ADO.NET Exception Handling Me.Response.Redirect("Resumes.aspx") Chapter 10 - Working with the ODBC .NET Data Provider End Sub Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Creating the Register.aspx Page



Now you a new Real-World Web page Web called Register.aspx to the application. This page reads the user ID, Chapter 17add - Building Applications

password, and email address of the user. The page looks like Figure 17-7, where three TextBox controls are used to enter the user ID, password, and email address. The Register button click action saves these Chapter 19 - Mapped Objects: Performance Considerations and Data Binding values to the database. The Back to Home Page button simply goes back to the Login.aspx page. Chapter 18 - Object-Relational Mapping in .NET



Figure 17-7: TheRegister.aspx page Listing 17-3 shows the code for both of the button click event handlers. As you can see from this code, for theRegister button, you construct a SqlCommand using an INSERT..INTO SQL query, add parameters and their values by reading from the TextBox controls of the page, and execute the query. This query adds a new record to the Users table of the database. Listing 17-3: The Register.aspx Code

Private Sub RegisterBtn_Click(ByVal sender As System.Object, _ ADO.NET: Building Data-Driven Solutions ByVal e As Applied System.EventArgs) Handles RegisterBtn.Click ISBN:1590590732 by Mahesh Chand and David Talbot If IsValid Then Apress © 2003 (928 pages) ' Create a connection provides extensive coverage of ADO.NET technology conn = This Newtext SqlConnection() including ADO.NET internals, namespaces, classes, and conn.ConnectionString = connectionString interfaces, and takes a comprehensive look at XML 'Open connection namespaces and classes, and how to integrate both with If conn.State ADO.NET. ConnectionState.Open Then conn.Open() End If Table of Contents ' Construct an INSERT query with parameters Applied ADO.NET—Building Data-Driven Solutions sql = "INSERT INTO Users(UserID, Password, Email) " & _ Introduction "VALUES (@id, @pass, @email)" Chapter 1 cmd - ADO.NET = New Basics SqlCommand(sql, conn) Chapter 2 cmd.CommandType - Data Components in=Visual CommandType.Text Studio .NET parameters withEnvironments values from text boxes Chapter 3 ' -Add ADO.NET in Disconnected IdTextBox.Text) Chapter 4 cmd.Parameters.Add("@id", - ADO.NET in Connected Environments PassTextBox.Text) Chapter 5 cmd.Parameters.Add("@pass", - Handling ADO.NET Events EmailTextBox.Text) Chapter 6 cmd.Parameters.Add("@email", - Integrating XML with ADO.NET Chapter 7


' Execute the query Chapter 8 - Constraints and Data Relations Try Chapter 9 - ADO.NET Exception Handling cmd.ExecuteNonQuery() Chapter 10 - Working with the ODBC .NET Data Provider Catch exp As Exception Chapter 11 - Stored Procedures and Views StatusBar.Text = exp.Message.ToString() Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers End Try Chapter 13 Developing a Custom Data Provider ' -Close connection Chapter 14 Developing Database Web Applications using ASP.NET Then If conn.State ConnectionState.Closed Chapter 15 -conn.Close() Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding End If Chapter 17 Building Real-World IdTextBox.Text = Web "" Applications Chapter 18 EmailTextBox.Text - Object-Relational Mapping = "" in .NET StatusBar.Text = "Thank Considerations you registring with us." Chapter 19 - Mapped Objects: Performance and Data Binding ChapterEnd 20 -If COM Interoperability and ADO.NET Chapter 21 - Messaging

End22Sub Chapter - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Private Sub BackBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles BackBtn.Click Appendix C - ADO.NET Frequently Asked Questions Response.Redirect("Login.aspx") Index End Sub Appendix B - Commonly Used SQL Statements



Creating the Contact.aspx Page The next page you add to the application is the Contact.aspx page. This page sends a message. As you can see from Figure 17-8, you have TextBox controls for From, To, Subject, and Message. The From box takes the email address you're sending the message from; the To box takes the email address to which you are sending to the message. The Subject and Message boxes represent the title and the message body of the email, respectively. The StatusBar control displays the status of the message.


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Figure 17-8: TheContact.aspx page

Chapter 3 -has ADO.NET in Disconnected This page only few lines of code Environments for the Send Message click event handler, which is shown in Listing Chapter 4 you - ADO.NET Connected Environments 17-4. As can seeinfrom this code, you simply create a MailMessage that represents a mail message Chapter and set5its -From, Handling To,Subject, ADO.NET Events and Body properties. After that we set SmtpMail.SmtpServer to the

server, 6from which we're sending the email. Our mail server is mail5.fiberspeed.net. You must Chapter - Integrating XML with ADO.NET change7it to your Binding email server. Chapter - Data and Windows Forms Data-Bound Controls Chapter 8


Listing 17-4: Send Message Click Event Handler - ADO.NET Exception Handling

Chapter 9


Private SendMailBtn_Click(ByVal sender As System.Object, _ Chapter 11 -Sub Stored Procedures and Views ByVal As System.EventArgs) SendMailBtn.Click Chapter 12 -eOracle, SQLXML, and Other .NETHandles Data Providers Chapter 13 - Developing a Custom Data Provider

As MailMessage = New MailMessage() ChapterDim 14 -msg Developing Database Web Applications using ASP.NET msg.To = ToTextBox.Text msg.From = FromTextBox.Text Chapter 16 - ASP.NET Server Controls and Data Binding msg.Subject = SubTextBox.Text Chapter 17 - Building Real-World Web Applications msg.Body = MsgTextBox.Text Chapter 18 - Object-Relational Mapping in .NET SmtpMail.SmtpServer = "mail5.fiberspeed.net" Chapter 19 - Mapped Objects: Performance Considerations and Data Binding SmtpMail.Send(msg) ChapterStatusBar.Text 20 - COM Interoperability and ADO.NET = "Message recieved. We will contact you soon. " Chapter 21 Messaging End Sub Chapter 15 - Using ADO.NET in Xml Web Services

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Creating the PostJob.aspx Page

Index

List of you Figures Now add the PostJob.aspx page to the project. This page posts a new job to the job board. This List of Tables page reads the information related to a job and adds to the Job table of the database. This page looks like List of Listings Figure 17-9. As you can see from this page, there are five TextBox controls to read the company name, List of Sidebars description of the job, contact person, requirements, and job details.


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3 - 17-9: ADO.NET Disconnected Environments Figure Thein PostJob.aspx page Chapter 4 - ADO.NET in Connected Environments Chapter 5


Besides the TextBox controls, this page also has three Button controls and a StatusBar control. The - Integrating XML with ADO.NET Post Job button click event handler reads data from the TextBox controls and adds it to the Job database Chapter 7 - Data Binding and Windows Forms Data-Bound Controls table.Listing 17-5 shows the code for the Post Job button click event handler. As you can see from this Chapter 8 -simply Constraints and a Data Relations using an INSERT..INTO SQL query, add its parameters, and code, you construct SqlCommand Chapter 9 ADO.NET Exception Handling execute the query. Chapter 6

Chapter 10 - Working with the ODBC .NET Data Provider Chapter Listing11 17-5: - Stored The Post Procedures Job Button and Views Click Event Handler Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 -Sub Developing a Custom Data Provider Private SaveBtn_Click(ByVal sender As System.Object, _ Chapter 14 -eDeveloping Database Web Applications usingSaveBtn.Click ASP.NET ByVal As System.EventArgs) Handles Chapterconn 15 - Using ADO.NET in Xml Web Services = New SqlConnection() Chapterconn.ConnectionString 16 - ASP.NET Server Controls = andconnectionString Data Binding Chapter'17 Construct - Building Real-World an INSERT Web Applications query with parameters

"INSERT INTO Job(Company, Contacts, Description, " & _ Chaptersql 18 -=Object-Relational Mapping in .NET Details, PostingDate) " &Data _ Binding Chapter"Requirements, 19 - Mapped Objects: Performance Considerations and @cont, @req, @des, @det, @post)" Chapter"VALUES 20 - COM (@comp, Interoperability and ADO.NET New SqlCommand(sql, conn) Chaptercmd 21 -=Messaging = CommandType.Text Chaptercmd.CommandType 22 - SQL Server and ADO.NET: Notes on Performance cmd.CommandText = sql ' Add parameters with values from text boxes Appendix B - Commonly Used SQL Statements cmd.Parameters.Add("@comp", CompanyTxtBox.Text) Appendix C - ADO.NET Frequently Asked Questions cmd.Parameters.Add("@cont", ContactsTxtBox.Text) Index cmd.Parameters.Add("@req", ReqTxtBox.Text) List of Figures cmd.Parameters.Add("@des", DesTxtBox.Text) List of Tables cmd.Parameters.Add("@det", DetailsTxtBox.Text) List of Listings cmd.Parameters.Add("@post", _ List of Sidebars SqlDbType.DateTime).Value = DateTime.Today.ToString() ' Open connection If conn.State ConnectionState.Open Then conn.Open() End If ' Execute the query cmd.ExecuteNonQuery() ' Close connection If conn.State ConnectionState.Closed Then conn.Close() End If ClearFields() Appendix A - Relational Databases: Some Basic Concepts

StatusBar.Text = "Thank you for Job Posting" Applied ADO.NET: Building Data-Driven Solutions End Sub by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

This text provides extensive coverage of ADO.NET technology ADO.NET internals, namespaces, classes, and in Listing 17-6. The Reset Fieldsincluding button simply clears the TextBox controls, as shown interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Listing 17-6: TheADO.NET. Reset Fields Click Event Handler

Private Sub ClearFields() CompanyTxtBox.Text = "" AppliedContactsTxtBox.Text ADO.NET—Building Data-Driven Solutions = "" Introduction ReqTxtBox.Text = "" ChapterDesTxtBox.Text 1 - ADO.NET Basics= "" ChapterDetailsTxtBox.Text 2 - Data Components in Visual = "" Studio .NET Chapter - ADO.NET in Disconnected Environments End3 Sub Chapter Private 4 - ADO.NET Sub ResetBtn_Click(ByVal in Connected Environments sender As System.Object, _ ByVal As System.EventArgs) Handles ResetBtn.Click Chapter 5 -eHandling ADO.NET Events ChapterClearFields() 6 - Integrating XML with ADO.NET End Sub Chapter 7 - Data Binding and Windows Forms Data-Bound Controls

Table of Contents

Chapter 8


Chapter 9



The Done button click event handler redirects the browser to the Login.aspx, as shown in Listing 17-7.


Chapter - Oracle, SQLXML, and Other Data Providers Listing12 17-7: The Done Button Click.NET Event Handler Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Private Sub DoneBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles DoneBtn.Click Chapter 16 - ASP.NET Server Controls and Data Binding Response.Redirect("Login.aspx") Chapter 17 - Building Real-World Web Applications End Sub Chapter 15 - Using ADO.NET in Xml Web Services

Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

Creating the PostResume.aspx Page

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix - Relational Databases: SomeisBasic Concepts The nextApage you add to the project the PostResume.aspx page. This page allows candidates to Appendix B Commonly Used SQL Statements post their resumes to the Job board. This page looks like Figure 17-10. As you can see from this page, Appendix ADO.NET Frequently Questions you haveC a- TextBox control forAsked the name, email address, resume title, address, and detailed projects Index handled of a candidate. The Education and Work Status combo boxes list the options for candidate's List of Figures education and work status. The Willing to Relocate radio buttons allow the candidate to set the option of List of Tables whether he is willing to relocate. List of Listings List of Sidebars


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Figure 17-10: ThePostResume.aspx page

Chapter Now let's 6 look - Integrating at the code. XMLYou withadd ADO.NET the options to the Education and Work Status combo boxes. Listing

17-8 shows the code. Asand youWindows can see,Forms the FillListBoxes methods add options to the combo boxes. Chapter 7 - Data Binding Data-Bound Controls Chapter 8


Listing 17-8: Adding Options to Post Resume Page - ADO.NET Exception Handling

Chapter 9


Private Page_Load(ByVal Chapter 11 -Sub Stored Procedures and Viewssender As System.Object, _ ByVal As System.EventArgs) MyBase.Load Chapter 12 -eOracle, SQLXML, and Other .NETHandles Data Providers user code to initialize Chapter'Put 13 - Developing a Custom Data Provider the page here ChapterFillListBoxes() 14 - Developing Database Web Applications using ASP.NET

End Sub


Private Sub FillListBoxes() ' This method adds selection data to list boxes Chapter 18 - Object-Relational Mapping in .NET EduList.Items.Add("Master's Degree") Chapter 19 - Mapped Objects: Performance Considerations and Data Binding EduList.Items.Add("Bachelor's Degree") ChapterEduList.Items.Add("Some 20 - COM Interoperability and ADO.NET College") ChapterEduList.Items.Add("2 21 - Messaging Yrs Diploma") ChapterStatusList.Items.Add("US 22 - SQL Server and ADO.NET: Notes on Performance Citizen") Appendix A Relational Databases: Some Basic Concepts StatusList.Items.Add("Green Card or Authorized to work") Appendix B - Commonly Used SQL Statements StatusList.Items.Add("H1 Visa") Appendix StatusList.Items.Add("Need C - ADO.NET Frequently Asked Questions Sponsorship") End Sub Index Chapter 17 - Building Real-World Web Applications

List of Figures List of Tables List of Listings

The Post Resume button click adds the contents of the page to the Resumes table of the database. Listing 17-9 shows the code for this button click event handler. As you can see, you again create a SqlCommand with an INSERT..INTO SQL query, sets its parameters by reading their values from the fields filled by the user, and execute the query. This option adds a new record to the Resumes table.

List of Sidebars

Listing 17-9: The Post Resume Button Click Event Handler Private Sub PostResumeBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles PostResumeBtn.Click conn = New SqlConnection() conn.ConnectionString = connectionString ' Construct an INSERT query with parameters sql = "INSERT INTO Resumes(Name, Email, Address, Resume, " & _

"Title, PostingDate, Education, Status, Relocate) " & _ Applied ADO.NET: Building Data-Driven Solutions "VALUES (@nam, @mail, @add, @res, @tit, @post, @edu, @stat, @rel)" ISBN:1590590732 by Mahesh Chand and David Talbot cmd = New SqlCommand(sql, conn) Apress © 2003 pages) cmd.CommandType = (928 CommandType.Text This text provides of ADO.NET technology ' Add parameters withextensive valuescoverage from text boxes including ADO.NET internals, namespaces, classes, cmd.Parameters.Add("@nam", NameTxtBox.Text) and interfaces, and takes a comprehensive look at XML cmd.Parameters.Add("@mail", namespaces and classes, andEmailTxtBox.Text) how to integrate both with cmd.Parameters.Add("@add", AddTxtBox.Text) ADO.NET. cmd.Parameters.Add("@res", ResumeTxtBox.Text) cmd.Parameters.Add("@tit", TitleTxtBox.Text) Table ofcmd.Parameters.Add("@post", Contents _ AppliedSqlDbType.DateTime).Value ADO.NET—Building Data-Driven Solutions = DateTime.Today.ToString() Introduction cmd.Parameters.Add("@edu", EduList.SelectedItem.Text.ToString) Chaptercmd.Parameters.Add("@stat", 1 - ADO.NET Basics StatusList.SelectedItem.Text.ToString) Chapter 2


Chapter 3

- ADO.NET in Disconnected Environments = 1) Then ChapterIf 4 (RadioButtonList1.SelectedIndex - ADO.NET in Connected Environments

"Yes") Chapter 5 cmd.Parameters.Add("@rel", - Handling ADO.NET Events ChapterElse 6 - Integrating XML with ADO.NET

"No") Chapter 7 cmd.Parameters.Add("@rel", - Data Binding and Windows Forms Data-Bound Controls End -If Constraints and Data Relations ' Open connection Chapter 9 - ADO.NET Exception Handling If conn.State ConnectionState.Open Then Chapter 10 - Working with the ODBC .NET Data Provider conn.Open() Chapter 11 - Stored Procedures and Views End If Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers ' Execute the query Chapter 8

Chapter 13 - Developing a Custom Data Provider ChapterTry 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services cmd.ExecuteNonQuery() ChapterCatch 16 - ASP.NET Server Controls and Data Binding exp As Exception Chapter 17 - Building Real-World Applications StatusBar.Text = Web exp.Message.ToString() ChapterEnd 18 -Try Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Close Chapter'20 - COM connection Interoperability and ADO.NET ConnectionState.Closed Then ChapterIf 21 conn.State - Messaging conn.Close() Chapter 22 - SQL Server and ADO.NET: Notes on Performance End Appendix A -If Relational Databases: Some Basic Concepts ClearFields() StatusBar.Text = "Thank you for posting your resume." Appendix C - ADO.NET Frequently Asked Questions End Sub Appendix B - Commonly Used SQL Statements Index

List of Figures List of Tables List of Done Listings The button click event handler simply redirects the browser to the Login.aspx page, as shown in List of Sidebars Listing 17-10.

Listing 17-10: The Done Button Click Event Handler Private Sub DoneBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles DoneBtn.Click Response.Redirect("Login.aspx") End Sub

Creating the DisplayData.aspx and Resumes.aspx Pages Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

The next two pages we'll discuss display the available resumes and jobs. Add two Web pages to the Apress © 2003 (928 pages) project called DisplayData.aspx and Resumes.aspx. The DisplayData.aspx page displays the This provides extensive coverage ADO.NET technology available jobs, and thetext Resumes.aspx page displaysofthe available resumes. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

To display the data, you'll use the DataList control. (We discussed the DataList control and data namespaces and classes, and how to integrate both with binding in Chapter 16.) The final DisplayData.aspx page looks like Figure 17-11. On this page, the ADO.NET. data is loaded when the page is loaded. The First Job, Previous Job, Next Job, and Last Job buttons move to the first, previous, next, and last jobs, respectively. The Home Page button redirects the browser to the Table of Contents Login.aspx page. Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Figure 17-11: TheDisplayData.aspx page


Listing 18 17-11 shows the complete code for the DisplayData.aspx page. As you can see from this Chapter - Object-Relational Mapping in .NET code, you templates to format and bind data to the template items. The tag Chapter 19 -use Mapped Objects: Performance Considerations and Data Binding displays20the data.Interoperability (See Chapter and 16 for more details about the DataList control and templates.) Chapter - COM ADO.NET Chapter 21 - Messaging

Listing 17-11: DisplayData.aspx HTML View


Listings .NET Jobs Listing DataList Control footer

Appliedface="verdana" ADO.NET: Building size="2"> Data-Driven Solutions Chapter 7 - Data Chapter 20 -= TotalRecords) Then Table of Contents CurrentIndex = TotalRecords - PageSize AppliedEnd ADO.NET—Building Data-Driven Solutions If Introduction FillPartialData(CurrentIndex) Chapter - ADO.NET Basics End1 Sub Chapter Private 2 - Data Sub Components LastBtn_Click(ByVal in Visual Studio .NET sender As System.Object, _ ByVal As System.EventArgs) Handles LastBtn.Click Chapter 3 -eADO.NET in Disconnected Environments TotalRecords - PageSize ChapterCurrentIndex 4 - ADO.NET in = Connected Environments ChapterFillPartialData(CurrentIndex) 5 - Handling ADO.NET Events End Sub Chapter 6 - Integrating XML with ADO.NET Chapter 7


Chapter 8


Chapter 9


TheResumes.aspx page displays available resumes. You again use a DataList control to display the resumes. The final Resumes.aspx page looks like Figure 17-12. On this page, the data is loaded when Chapter 11 - Stored Procedures and Views the page is loaded. The First Resume, Previous Resume, Next Resume, and Last Resume buttons move Chapter 12 -previous, Oracle, SQLXML, and Other .NET Data Providers to the first, next, and last resume, respectively. Chapter 10 - Working with the ODBC .NET Data Provider

Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions IndexFigure 17-12: TheResumes.aspx page List of Figures List of Tables Listing 17-15 shows the complete code for the Resumes.aspx page. As you can see from this code, you List Listings to format and bind data to the template items. The tag displays the useoftemplates List of Sidebars data. (See Chapter 16 for more details about the DataList control and templates.)

Listing 17-15: Resumes.aspx HTML View Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Candidate ADO.NET. Name: Table of Contents Title: Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1 -Email: ADO.NET Basics Chapter 2 - Chapter 3 - ADO.NET in Disconnected Environments Chapter 4


Chapter 5

-Address: Handling ADO.NET Events

Chapter 6

DataBinder.Eval(Container.DataItem, "Address")%> - Chapter 20 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures Chapter 8



The code for filling data from the Resumes table to the DataList control and navigating through the Table of Contents resumes is the same as the code you saw on the DisplayData.aspx page for displaying a job. You just Applied Data-Driven Solutions need toADO.NET—Building change the database table name from Job to Resumes in the FillDataGrid method. The rest Introduction is the same. For more details, download the source code from the Apress Web site (www.apress.com). Chapter 1 - ADO.NET Basics Chapter 2

- Data Components in Visual Studio .NET Creating the dnjHeader.aspx Page

Chapter 3


Chapter 4 one - ADO.NET in Connected There is more thing left to do. Environments To make the application a little more interactive, you'll design one more page called dnjHeader.aspx. This page has an image and two HyperLink controls: Home Page and Chapter 5 - Handling ADO.NET Events

Contact6 Us. The HomeXML Page linkADO.NET simply redirects the browser to the Login.aspx page, and the Contact Chapter - Integrating with Us link 7redirects browser to the Contacts.aspx page. This page works as a header of he job board. Chapter - Data the Binding and Windows Forms Data-Bound Controls That means every pageand of the job board application includes this page. Figure 17-13 shows the Chapter 8 - Constraints Data Relations dnjHeader.aspx Chapter 9 - ADO.NETpage. Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - 17-13: SQL Server and ADO.NET: Notespage on Performance Figure ThednjHeader.aspx Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

To include the dnjHeader.aspx page, you use the INCLUDE keyword. The third line in the following code includes the page to other pages. You want to make sure you change the path of the page to your Index application's path: Appendix C - ADO.NET Frequently Asked Questions List of Figures List of Tables

List of Listings Resumes

List of Sidebars

Running the Application Now you're ready to run the application. When you run the application, the Login.aspx page will be the first page, which looks like Figure 17-14.


ISBN:1590590732


Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Figure 17-14: The job board Chapter 1 - ADO.NET Basics Chapter 2


Once you register and log in to the site, you'll see job and resume options. You can test the application by - ADO.NET in Disconnected Environments posting a few resumes and jobs. After posting a few jobs and resumes, you can view the jobs and Chapter 4 - ADO.NET in Connected Environments resumes by using the View Jobs and View Available Resumes buttons. The View Jobs page looks like Chapter 5 - Handling ADO.NET Events Figure 17-15. You can use the buttons to move to the next, previous, first, and last job available in the Chapter 6 - Integrating XML with ADO.NET database. Chapter 3

Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions IndexFigure 17-15: View Jobs page List of Figures List of View Tables The Resumes page looks like Figure 17-16. You can use the buttons to move to the next, previous, List Listings firstofand last job available in the database. List of Sidebars


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7 - 17-16: Data Binding and Windows Figure The View ResumesForms pageData-Bound Controls Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions Improving and Modifying the Application by Mahesh Chand and David Talbot

ISBN:1590590732

To keep in mind the size© of this book and the chapter, we tried to limit the functionality of the Job Board Apress 2003 (928 pages) application. However, you can modify the existing application to build a Job Board application with some This text provides extensive coverage of ADO.NET technology more user-friendly features. Some of the possible improvements to the including ADO.NET internals, namespaces, classes, and application could be the following: interfaces, and takes a comprehensive look at XML namespaces andonclasses, and page how to integrate both with Adding the latest job listing the home ADO.NET.

Adding the latest resume listing on the home page Table of Contents Adding a search feature that can search jobs and resumes based on keywords Applied ADO.NET—Building Data-Driven Solutions

Adding features such as a resume builder, search saves, personal pages, and other resources that Introduction can1 help candidates to build their resume online Chapter - ADO.NET Basics Chapter 2

- Data Components in Visual Studio .NET Categorizing jobs based on the state or country (if there is enough traffic on your site)

Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Summary


ISBN:1590590732

In this chapter, you learned how build a real-world job application where employers can post their jobs Apress © 2003 (928topages) and candidates can post their resumes. Object databases are quite useful in many situations, and as a This text provides extensive coverage of ADO.NET technology developer there are quite a few situations when you need to deal with including ADO.NET internals, namespaces, classes, and object databases as well as interfaces, and takes a comprehensive look at XML relational databases. namespaces and classes, and how to integrate both with ADO.NET. In the following chapter, we cover object and relational database mappings. You'll learn the basics of the

object-mapped data model and how to create a simple video store application that allows users to load, create, and alter videos in the library as well as check in and out videos. You'll learn how to create Table of Contents mapped objects as well as workarounds for common pitfalls and quirks found in ADO.NET that can Applied ADO.NET—Building Data-Driven Solutions adversely affect your data model. Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 18: Object-Relational Mapping in .NET ISBN:1590590732 by Mahesh Chand and David Talbot

Overview


This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Relational databases interfaces, treat data and takes in terms a comprehensive of rows and columns, look at XML and objects treat things in terms of arrays namespaces and mapping classes, and to integrate boththese with two worlds so your code can look and properties. Object-relational (ORhow mapping) bridges ADO.NET.

like object code and still store itself in a relational database.

In this chapter, you'll create a simple object data model for a video store application. You'll learn how to create mapped objects as well as workarounds for common pitfalls and quirks found in ADO.NET that can Applied ADO.NET—Building Data-Driven Solutions adversely affect your data model. Let's start by discussing why you may need to worry about OR mapping.


Chapter 1 - ADO.NET OR mapping providesBasics three main benefits: Chapter 2 - Data Components in Visual Studio .NET Chapter 3


Encapsulation: This is one of the primary pillars of object-oriented design, and OR mapping extends - ADO.NET in Connected Environments this concept to the database.

Chapter 4 Chapter 5


Chapter 6

- Integrating XML with ADO.NET Identity: A mapped object has anForms identity. In concrete terms it has a unique identifier. Most objects Chapter 7 - Data Binding and Windows Data-Bound Controls

that are not mapped to a database lack a real identity independent of the data presented to the end - Constraints and Data Relations user. Although it's possible to create an identity for the objects using hashcodes or a similar Chapter 9 - ADO.NET Exception Handling methodology, mapped objects take this to the next logical level. Chapter 8


Behavior: DataSQLXML, in a database does notData haveProviders behavior. By fusing the world of databases to software Chapter 12 - Oracle, and Other .NET code, have theaunique to define how your data should interact with your system in a Chapter 13 -you Developing Customopportunity Data Provider clean reusableDatabase way. Chapter 14 -and Developing Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Visual Basic .NET (VB .NET) takes the partial support for object-oriented programming found in VB 6 to the next level. By leveraging this expanded capability in VB .NET, you're presented with an opportunity to Chapter 17 - Building Real-World create powerful object systemsWeb withApplications persistence into a medium that allows for easy integration with other Chapter 18and - Object-Relational in on .NET systems a simple way ofMapping reporting that data. Chapter 16 - ASP.NET Server Controls and Data Binding


Applied ADO.NET: Building Data-Driven Solutions Why Not Just Use a DataSet? by Mahesh Chand and David Talbot

ISBN:1590590732

ADO.NET supplies you © with a (928 number Apress 2003 pages)of powerful objects including DataSet objects to provide a means of accessing andThis presenting data, these coverage objects fall in situations where you need to provide a text provides but extensive of short ADO.NET technology clear contract between the data and your object system. They also fall short in situations when you require including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look atmediums, XML complex validation, portability between multiple persistence or abstraction of data operation. namespaces and classes, and how to integrate both with So, when does a ADO.NET. programming problem require a clear contract to be defined between the data and the

code? A good example is a situation where the data provides a means of recording history that then requires business logic to be applied to it before presenting it to the user or making a decision. For Table of Contents example, an order entry system requires that logic be applied to a user's entries before being stored into a Applied ADO.NET—Building Data-Driven Solutions database to determine if the user can purchase the selected items. This is a prime candidate for objectIntroduction relational mapping. Chapter 1

- ADO.NET Basics

Chapter - Data Components in Visualcan Studio .NET Another2 situation when OR mapping really help is when you have the need to enforce complicated Chapter 3 - ADO.NET in Disconnected Environments data validation. Databases support enforcing relations and null vs. non-null values, but they do not (in Chapter general) 4 have - ADO.NET good support in Connected for complex Environments validation. For example, if you need to make sure the user has

provided oneADO.NET method of contact (such as a phone or email address), you can easily enforce this Chapter 5 at - least Handling Events with a mapped object. XML with ADO.NET Chapter 6 - Integrating Chapter 7


Many packaged applications need to be able to store the application data in multiple database systems Chapter 8 - Constraints and Data Relations and even be able to support situations where the user purchasing the software has no database at all Chapter 9 - ADO.NET Exception Handling (such as a flat text file). By keeping your application logic and data model in your objects, support for each Chapter 10 - Working with the ODBC .NET Data Provider persistence medium is as simple as adding handling in the data access components. If you use direct SQL Chapter 11 procedure - Stored Procedures and Views or stored calls throughout your code, you'll find portability a major problem. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

The classic view of ORamapping involves abstracting a complex data model. A classic example is if you Chapter 13 - Developing Custom Data Provider have the to track Database employees, salespeople, An employee is clearly the "base class" Chapter 14need - Developing Web Applications and usingaccountants. ASP.NET for the 15 other typesADO.NET of employees. For example, Chapter - Using in Xml Web Services all employees have name information, but only sales people16 have a sales Server territoryControls code, and have a CPA certification flag. You would put the Chapter - ASP.NET and only Dataaccountants Binding common in theReal-World EmployeeWeb object (and related table in the database) and the task-specific information Chapter 17 parts - Building Applications in a related object (and related table in the database).


Chapter Mapped Objects: Performance and Data Binding an easily manageable system. In all of19 the- previous cases, you'll find ORConsiderations mapping beneficial in creating Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

AppliedObject ADO.NET:Databases Building Data-Driven Solutions Understanding by Mahesh Chand and David Talbot

ISBN:1590590732

Object databasesApress such as Objectivity/DB, Poet, and Matisse started appearing in the 1980s as a proposed © 2003 (928 pages) alternative to transaction-oriented relational management systems. The idea was to treat data This text provides extensive database coverage of ADO.NET technology more intuitively asincluding objects ADO.NET (Customer and Invoice objects, for example) internals, namespaces, classes, and instead of as a series of flat rows interfaces, and and takesrelated a comprehensive XMLa good overview of object databases, see that have to be stored in tables via foreign look keys.at(For and classes, and how to integrate both with Doug Barry's sitenamespaces at www.odbmsfacts.com/articles/object-oriented_databases.html.) ADO.NET.

A simple way of thinking about object databases is looking at how you would create a simple program that shows a list of all the users in your database. Table of Contents Applied Using ADO.NET—Building SQL to get this dataData-Driven from your Solutions relational database, you would use the following statement: Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


SELECT * FROM Users

Chapter 4 - then ADO.NET Environments You would havein toConnected take the data returned from the query, transform it into objects in your code, Chapter iterate through 5 - Handling a list of ADO.NET users, and Events display the results. This is a hard-nosed look at the problem; technically

you can6 just pipe the results directly out from the database, but in doing so you give up the encapsulation Chapter - Integrating XML with ADO.NET promised object-oriented Chapter 7 by - Data Binding and programming. Windows Forms Data-Bound Controls Chapter 8


Chapter 9


Using an object database, your code would look similar to the following statement:


Dim users As Users() users = open('users').Load()

Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 -allDeveloping Web Applications using of ASP.NET For listing users, theDatabase object database wins in terms simplicity. The data is acquired, and it's already Chapter 15 Using ADO.NET in Xml Web Services an object with no need for a transformation to work with it. All you would need to do then is loop through Chapter 16 - ASP.NET Server Controls and Data Binding the collection of users objects. Chapter 17 - Building Real-World Web Applications

It gets a18lot- more complicatedMapping when you want to perform a "reporting" type of function on the database Chapter Object-Relational in .NET such as19getting the total amount of ordersConsiderations to be shippedand on aData future date. Chapter - Mapped Objects: Performance Binding Chapter 20 - COM Interoperability and ADO.NET

In SQL you can use the following syntax:



SELECT sum(Amount) FROM OrderedItems WHERE ShipDate > GetDate()


Appendix - ADO.NET Frequently Asked Questions With an C object database you would have to actually loop through all of the items in the OrderedItems Index collection and add each amount to the total. There are other options that different object database List vendors of Figures support for summarizing data, but the options overall are not as simple and consistent as they are

withofSQL tables. List Tables List of Listings

Ultimately, object databases never caught on for a variety of reasons. Some people feel strongly about to say that object databases are inferior to relational databases, but in the end the marketplace has spoken and the number of object databases in actual use in production systems is tiny.

List of Sidebars

So, although it's unlikely you'll ever run into a project that uses an object database, you can still work with objects in your code that store their properties in a database transparently, which allows you to focus on developing new functionality instead of worrying about breaking old code.

ADO.NET:Mapping? Building Data-Driven Solutions Why ObjectApplied Relational by Mahesh Chand and David Talbot

ISBN:1590590732

OR mapping keeps the © code your application encapsulated and clean, and it makes it easy to manage Apress 2003 in (928 pages) changes in the database. By building an OR coverage mappingofcomponent, your database logic will be This text provides extensive ADO.NET technology encapsulated andincluding hidden ADO.NET away frominternals, the rest namespaces, of your system. Because classes, and the logic of loading and saving your interfaces, andmapping takes a comprehensive at in XML object rests entirely in the OR subsystem, thelook code the rest of your program uses only clean namespaces and classes, and how to integrate bothtowith object-oriented code. It also makes it far easier to make changes the database later without having to ADO.NET. alter every place you reference the data. The core issue is short-term vs. long-term laziness. Using short-term laziness would probably put SQL queries directly in your Web pages and just use SqlDataReader objects to work with your data. Past the Applied ADO.NET—Building Data-Driven Solutions initial implementation, this method makes your code hard to maintain. If you add a column to the Introduction database, you'll have to find every reference to that table in your application and update it. Also, as the Chapter 1 - ADO.NET Basics need to use the same table on multiple pages arises, you'll find yourself copying and pasting large Chapter 2 - Data Components in Visual Studio .NET sections of code to get the same functionality on these new pages as well.

Table of Contents

Chapter 3


Chapter Long-term 4 -laziness ADO.NETmeans in Connected taking the Environments upfront time costs associated with building out the object relational

mapping your table. It will definitely Chapter 5 for - Handling ADO.NET Events take you longer to initially produce these objects, but in the long term it will much XML less with work. Chapter 6 -mean Integrating ADO.NET Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Creating the Basic Design of the VideoSolutions Store Application by Mahesh Chand and David Talbot

ISBN:1590590732

The OR mappingApress technique in this chapter was inspired by a demo application from Microsoft intended to © 2003used (928 pages) show best practices in .NET called Duwamish7. Downloading Duwamish7, This text provides extensive coverage of ADO.NET technologyreading through the source code, and truly understanding how it works can really help you become a much including ADO.NET internals, namespaces, classes, and better .NET programmer. It covers topics interfaces, and takes logical a comprehensive look at XML and more. Download it from MSDN such as statelessness, OR mapping, three-tier structures, namespaces and classes, and how for to integrate both with (http://msdn.microsoft.com) by searching Duwamish7. ADO.NET.

Understanding the Basic Architecture

Table of Contents

Applied Solutions Three ADO.NET—Building objects make up aData-Driven mapped object. These are the data object, the mapped object, and the Data Access Introduction Component (DAC). The DAC creates and fills the data object with data, then passes a single row of that data to

create an of Basics the mapped object. Chapter 1 instance - ADO.NET Chapter 2


The data object is simply an in-code representation of the database table you plan on using for an object. In .NET - ADO.NET in Disconnected Environments specifically, it's a subclassed DataTable or DataSet where you have defined what the columns names are as Chapter 4 - ADO.NET in Connected Environments well as the data types. The application outside of the mapping never uses this object directly. Chapter 3 Chapter 5


Chapter 6 - Integrating XML with ADO.NET The mapped object uses your data object to point to a particular row of the DataTable found in the data object Chapter 7 Data Binding and Windows Data-Bound Controls property names. The mapped object is the and maps the column names from theForms data object to easy-to-use Chapter primary8interface - Constraints between andthe Data rest Relations of your application and your data. Chapter 9


The DAC is the glue that holds the data object and the mapped object together and persists the changes to the database. The DAC defines what stored procedures or database queries are necessary to load, insert, update, or Chapter 11 - Stored Procedures and Views delete your object's data from the database. Figure 18-1 shows the basic concept of OR mapping. Chapter 10 - Working with the ODBC .NET Data Provider


Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Figure 18-1: Basic concept of OR mapping


Creating the Database Design of the Video Store

Index

List of example Figures for this chapter builds all of the data objects required for a simple video store application. It's The List of Tables probably too much to consider it a complete video store because you're not actually tracking money and late fees, List Listings butofit'll do quite well to help you track your own video collection. It'll also come in handy if you have friends who List of Sidebars borrow videos from you and you need to remember whom you let borrow what.

The design of the video store database is simple. At the core of this application is the VideoTape table, as shown in Table 18-1. The VideoTape table tracks only the title and description of the title in question. You could have quite a bit more information about a particular title and even expand the application to track DVDs as well as video tapes, but for this application, let's keep it simple. You can always expand this later to create a complete application. Table 18-1: The VideoTape Table

COLUMN NAME Applied SQL SERVERBuilding DATA TYPE ADO.NET: Data-Driven Solutions VideoTapeID Title Description

by Mahesh Chand and David Talbot Numeric Apress © 2003 (928 pages)

.NET DATA TYPE

ISBN:1590590732

Decimal

This text Char provides (50) extensive coverage of ADO.NET technologyString including ADO.NET internals, namespaces, classes, and Text and takes a comprehensive look at XML String interfaces, namespaces and classes, and how to integrate both with ADO.NET.

The VideoTape table relates to the VideoCheckIn table (shown in Table 18-2) and the VideoCheckOut table (shown in Table 18-3) to model what is checked in and out. It also relates to the Users table to track who participated in the transaction. The information tracked in each table is the VideoTapeID, the date it was checked Table of Contents in or out on, the user whoData-Driven performed Solutions the check in or out, and the user to whom it was checked in or out. Applied ADO.NET—Building Introduction

Table 18-2: The VideoCheckIn Table - ADO.NET Basics

Chapter 1

Chapter 2 - NAME Data ComponentsSQL in Visual StudioDATA .NET TYPE COLUMN SERVER Chapter 3 - ADO.NET in Disconnected Environments

.NET DATA TYPE

VideoTapeID Numeric Chapter 4 - ADO.NET in Connected Environments

Decimal

Chapter 5 - Handling ADO.NET Events CheckedInOn Smalldatetime

DateTime

Chapter 6


CheckedInByUserID Numeric - Data Binding and Windows Forms Data-Bound Controls Chapter 8 - Constraints and Data Relations CheckedInFromUserID Numeric Chapter 7 Chapter 9


VideoCheckOutID

Numeric


Decimal Decimal Decimal


Table 18-3: The VideoCheckOut Table

Chapter 13 - Developing a Custom Data Provider Chapter COLUMN 14 - NAME Developing Database SQL Web SERVER Applications DATA using TYPEASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

VideoCheckOutID

Numeric

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications VideoTapeID Numeric Chapter 18 - Object-Relational Mapping in .NET

CheckedOutOn

Smalldatetime

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter CheckedOutByUserID 20 - COM Interoperability Numeric and ADO.NET Chapter 21 - Messaging

CheckedOutToUserID

Numeric


.NET DATA TYPE Decimal Decimal DateTime Decimal Decimal

Appendix A - Relational Databases: Some Basic Concepts Appendix B -table Commonly SQL Statements The Users tracksUsed the people involved with the system (see Table 18-4). In a real-world situation, you would Appendix C - ADO.NET Frequently Asked Questions also provide a Login table so that the people involved with the system can log in and an access control system Index controls which users can actually check things in and out. Of course, to run a video store with this application,

you'd also have to handle accounting and more, so don't get any ideas that this is a full-fledged application! List of Figures List of Tables

Table 18-4: The Users Table List of Listings List of Sidebars

COLUMN NAME

SQL SERVER DATA TYPE

.NET DATA TYPE

UserID

Numeric

Decimal

FirstName

Char (20)

String

LastName

Char (20)

String

We selected this particular application because it provides the opportunity to touch on many of the real-world issues you'll run in to when attempting to create a scalable Web application using .NET. Some of the topics ahead cover how to handle potentially large sets of data among dependant tables, how to manage the disconnects between the database's handling of null values, and how .NET handles null values. Additionally, you'll see some practical considerations to keep in mind when designing a scalable system with .NET.

Applied Creating the DataADO.NET: ObjectBuilding Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

The data object represents what table structure in the database is in your code. The data object is necessary Apress © 2003 (928the pages) for type safety and to text provide a "bucket" for your data.ofYou'll havetechnology to create a data object for each object in your This provides extensive coverage ADO.NET database. You'll start by examining the VideoTapeData object, shown in Listing 18-1. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML and classes, and how to integrate both with Listing 18-1: Thenamespaces VideoTapeData Object ADO.NET.

Public Class VideoTapeData Table ofInherits Contents DataTable Applied ADO.NET—Building Data-Driven Solutions Introduction Public Sub New() Chapter 1

-MyBase.New("VideoTape") ADO.NET Basics

Chapter 2

Type.GetType("System.Decimal")) -Me.Columns.Add("VideoTapeID", Data Components in Visual Studio .NET

Chapter 3

Type.GetType("System.String")) -Me.Columns.Add("Title", ADO.NET in Disconnected Environments

Chapter 4

Type.GetType("System.String")) -Me.Columns.Add("Description", ADO.NET in Connected Environments

Chapter 5


End -Sub Integrating XML with ADO.NET End Class

Chapter 6 Chapter 7


Chapter 8


Chapter 9


Chapter 10 -isWorking with the .NETthe Data Provider This code fairly simple. YouODBC declare VideoTapeData object as inheriting from the DataTable object. Chapter 11 Stored Procedures and Views Basically what you're doing is taking the functionality of the existing DataTable object and turning it into a custom Chapter 12 -Inside Oracle, and Other .NET Data Providers data type. theSQLXML, constructor, you call the base class by calling MyBase.New to call the constructor of the Chapter 13 - Developing a Custom Datafor Provider DataTable object. The constructor the DataTable object you're using in this example sets the table's name. Chapter 14 - Developing Database Web Applications using ASP.NET

The rest constructor sets the names of each column as in the database and provides the .NET data types of Chapter 15of- the Using ADO.NET in Xml Web Services each column. For example, the SQL Server data type Numeric is the Decimal object in .NET. The char and text fields both map to the same .NET type, String.


Chapter 18 - Object-Relational Mapping in create .NET a "typed" DataTable instead of using a regular untyped table is to The reason for taking this extra step to Chapter 19extra - Mapped Performance Considerations and Data Binding add one layer Objects: of data integrity. If a stored procedure returns more fields than this data object can handle, an Chapter 20be - COM Interoperability ADO.NET that you've altered the data returned by a stored procedure without error will thrown immediately,and highlighting Chapter - Messaging putting 21 proper handling for it in your code. Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Creating the Mapped Object


Appendix C - ADO.NET Asked Questions The mapped object isFrequently the front-end object that your application will use to interact with the database. The purpose Index of this object is to translate the data fields from the data object into easily managed fields in your object. This List object of Figures is where you encapsulate the core logic of your object and what it's supposed to do. List of Tables

Wherever possible, you should make your stored procedures as, well, "dumb" as possible. If a stored procedure has more logic than to save or get data, then there's likely a problem with your system design.

List of Listings

List of Sidebars

That said, sometimes it does make sense to put logic in your database where absolutely required for performance reasons. A common example is in the security management of your system. There are some situations where the security management part of your system needs to query across a large table and return only the results that the logged-in user has the access to see. In this case it may make sense to put a subset of your security system's logic in a subquery of your Select statement. Part of good design is knowing when to throw out an otherwise beautiful design for performance reasons. Any time you do this, always take a careful look at your design and try to come to a decision as to whether your design is flawed or this is just a sacrifice that has to be made for performance within the context of the situation (see Listing 18-2). Listing 18-2: The VideoTape Object

Public Class VideoTape Building Data-Driven Solutions ProtectedApplied data ADO.NET: As DataTable ISBN:1590590732 by Mahesh Chand and David Talbot Protected index As Integer Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology Protected Friend ReadOnly Property MyData() As DataRow() including ADO.NET internals, namespaces, classes, and Get interfaces, and takes a comprehensive look at XML Dim myRow() Asand DataRow = {Me.data.Rows(index)} namespaces and classes, how to integrate both with Return myRow ADO.NET.

End Get Table Contents End ofProperty Applied ADO.NET—Building Data-Driven Solutions Introduction Public Sub New(ByRef data As VideoTapeData, ByVal index As Integer) Chapter 1 -Me.data ADO.NET Basics = data Chapter 2

-Me.index Data Components = index in Visual Studio .NET

Chapter 3

Sub in Disconnected Environments -End ADO.NET

Chapter 4


Chapter 5

GetColumn(ByRef ColumnName As String) As Object -Public Handling Function ADO.NET Events

Chapter 6

Return - Integrating XMLdata.Rows(index)(ColumnName) with ADO.NET

Chapter 7

-End Data Function Binding and Windows Forms Data-Bound Controls

Chapter 8


Public Function SetColumn(ByRef ColumnName _ - ADO.NET Exception Handling As String, ByRef ColumnValue As Object) Chapter 10 - Working with the ODBC .NET Data Provider data.Rows(index)(ColumnName) = ColumnValue Chapter 11 - Stored Procedures and Views End Function Chapter 9


Chapter 13 -Public Developing a Custom Data Provider Property VideoTapeID() As Decimal Chapter 14 - Developing Database Web Applications using ASP.NET Get Chapter 15 - Using ADO.NET in Xml Web Services If (GetColumn("VideoTapeID").GetType() Is _ Chapter 16 ASP.NET Server Controls and Data Binding Type.GetType("System.DBNull")) Then Chapter 17 - Building Real-World Web Applications Return -1 Chapter 18 - Object-Relational End If Mapping in .NET

Return CType(GetColumn("VideoTapeID"), Decimal) Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Get Chapter 20 - COM End Interoperability and ADO.NET Set(ByVal Value As Decimal) Chapter 21 - Messaging Value) Chapter 22 - SQL ServerSetColumn("VideoTapeID", and ADO.NET: Notes on Performance End Databases: Set Appendix A - Relational Some Basic Concepts End Property

Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of List of List of List of

Public Property Title() As String Get Figures Return "" + GetColumn("Title") Tables End Get Listings Set(ByVal Value As String) Sidebars SetColumn("Title", Value) End Set End Property Public Property Description() As String Get Return "" + GetColumn("Description") End Get Set(ByVal Value As String) SetColumn("Description", Value) End Set End Property

End Class


ISBN:1590590732


The constructor of the VideoTape object takes a VideoTapeData object and an integer as its arguments. The including ADO.NET internals, namespaces, classes, and VideoTapeDatainterfaces, object actually holds the data, and the and takes a comprehensive lookinteger at XMLindex passed-in tells this object the row in the VideoTapeDatanamespaces DataTable andfor classes, whichand thishow instance to integrate of the VideoTape both with object is mapping. ADO.NET.

MyData is a read-only property that returns the DataRow that this object represents. The data access component uses MyData to get a reference to the VideoTapeobject's data. It was declared as a protected friend so that Table of Contents only other objects in this namespace can use it. The purpose of this is to hide this property from the rest of your Applied ADO.NET—Building Solutions program and remove theData-Driven temptation other programmers might feel in trying to use the your object's data directly. Introduction

Each of1 the object's properties being mapped need the ability to get and set the values of the database field that Chapter - ADO.NET Basics corresponds withComponents their values.inTo helpStudio with this task, we've included two functions, GetColumn and SetColumn, Chapter 2 - Data Visual .NET that allow rest of the object's properties to avoid having to use the complete ADO.NET syntax for referencing a Chapter 3 the - ADO.NET in Disconnected Environments particular and column. It's helpful to just think of the columns involved. By saving what row is being Chapter 4 row - ADO.NET in Connected Environments manipulated as plumbing that Events specifies the particular row of interest in this object, you can greatly simplify your Chapter 5 - Handling ADO.NET code.

Chapter 6


Chapter 7 - Data Binding and Windows Controls In the VideoTapeID property, do youForms noticeData-Bound the check to see if the value of the column is System.DBNull? Chapter Constraints and Data Relations This is 8an -interesting disconnect between the database's view of values and .NET's. Because .NET's primitive Chapter 9 - as ADO.NET Exception Handling types such Integers, Decimals, Strings,DateTimes, and Guids are value types, they do not have a null Chapter state. 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

You can an example of .NET's lack.NET of null for certain types with the DateTime object. If you declare a Chapter 12see - Oracle, SQLXML, and Other Datavalues Providers variable such as a DateTime and never initialize it with any given value, it's still given a value by .NET. The following statement prints 01/01/0001 even though myDate was never initialized:



Dim myDate As DateTime Chapter 16 - ASP.NET Server Controls and Data Binding Console.WriteLine(myDate.ToShortDateString()) Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped object, Objects: Performance Considerations Bindingthat a null pointer exception doesn't occur. In the VideoTape take a look at the checking it and doesData to ensure Chapter 20 COM Interoperability and ADO.NET In the getter of the property, a check is made to see if the type of the column is System.DBNull. If it is, then it Chapter returns21 -1 -toMessaging indicate that the value is not initialized to your .NET program. Otherwise, it casts the type of the Chapter 22 Server and ADO.NET: Notes to onthe Performance column to -aSQL decimal and returns the result calling program: Appendix A - Relational Databases: Some Basic Concepts Appendix B -Public Commonly Used SQL Statements Property VideoTapeID() As Decimal Appendix C - ADO.NET Frequently Asked Questions Get Index

If (GetColumn("VideoTapeID").GetType() Is _

List of Figures Type.GetType("System.DBNull")) Then List of Tables Return -1 List of Listings

End If Return CType(GetColumn("VideoTapeID"), Decimal) End Get Set(ByVal Value As Decimal) SetColumn("VideoTapeID", Value) End Set End Property

List of Sidebars

The database meanwhile treats data that hasn't been given a value as null. This becomes a problem when you try to move the content from the database into .NET because .NET needs to be able to represent the database's null value to the rest of your application in a way that lets your application know that a column has not been initialized. This includes things such as using -1 as a value for integers and decimals, an empty string for strings, and so on.

The trip back to the database compounds this problem. When the data is stored, if you have written a value to your ADO.NET:DateTime, Building Data-Driven data object such Applied as an uninitialized an error willSolutions occur. By handing these problems in the mapped ISBN:1590590732 by Mahesh Chand and David Talbot object, you'll make the rest of your program more reliable by preventing value checks throughout your code. Apress © 2003 (928 pages)

The two string fields mappedextensive in this object are easier to handle. If the database has a character field, such Thisbeing text provides coverage of ADO.NET technology including internals, namespaces, classes, andThe handling on the .NET side is easier than as a Char or Text, that's ADO.NET null, it'll return a System.DBNull object. interfaces, and takes a comprehensive look at XML with other value types. namespaces and classes, and how to integrate both with ADO.NET.

The following statement returns the value if there is one: Table of Contents Return "" + GetColumn("Description") Applied ADO.NET—Building Data-Driven Solutions Introduction

If the column is null in the database, it returns an empty string because ""+calls the ToString method on the - ADO.NET Basics System.DBNull object. Either way, an acceptable .NET value is returned to the calling program.

Chapter 1 Chapter 2


Chapter 3


Creating the Data Access Component - ADO.NET in Connected Environments

Chapter 4 Chapter 5


The DAC's- responsibility is to fill your data objects with data from the database and create instances of your Integrating XML with ADO.NET mapped object. It does this by defining what stored procedures should be used to load and save your data and Chapter 7 - Data Binding and Windows Forms Data-Bound Controls makes them accessible to simple front-end methods. Once the DAC is done, the rest of your program will be able Chapter 8 - Constraints and Data Relations to get and set your mapped objects just as easy as calling a simple method (see Listing 18-3). Chapter 6

Chapter 9


Chapter - Working with the ODBC .NET Data Provider Listing10 18-3: The VideoTapeDataAccess Object Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Public Class VideoTapeDataAccess

Chapter 13 - Developing a Custom Data Provider ChapterPublic 14 - Developing Database Web Applications using ASP.NET connectionString As String Chapter 15 -Protected Using ADO.NET in Xml Web adapter AsServices SqlDataAdapter Chapter 16 -Protected ASP.NET Server Controls and Binding loadAll As Data SqlDataAdapter Chapter 17 - Building Real-World Web Applications Chapter 18 -Public Object-Relational Mapping in .NET Sub New() Chapter 19 - Mapped connectionString Objects: Performance="Your Considerations Connection and Data Binding String" Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

adapter = New SqlDataAdapter() Chapter 22 - SQL Server and ADO.NET: Notes on Performance adapter.SelectCommand = New SqlCommand("ap_VideoTapeLoadByID", _ Appendix A - Relational Databases: Some Basic Concepts New SqlConnection(connectionString)) Appendix B - Commonly Used SQL Statements adapter.SelectCommand.CommandType = CommandType.StoredProcedure adapter.SelectCommand.CommandType = CommandType.StoredProcedure Index adapter.SelectCommand.Parameters.Add _ List of Figures ("@VideoTapeID", SqlDbType.Decimal, 0, "VideoTapeID") List of Tables adapter.InsertCommand = New SqlCommand("ap_VideoTapeInsert", _ List of Listings New SqlConnection(connectionString)) List of Sidebars adapter.InsertCommand.CommandType = CommandType.StoredProcedure adapter.InsertCommand.Parameters.Add("@VideoTapeID", _ SqlDbType.Decimal, 0, "VideoTapeID") adapter.InsertCommand.Parameters("@VideoTapeID").Direction = _ ParameterDirection.Output adapter.InsertCommand.Parameters.Add("@Title", _ SqlDbType.Char, 50, "Title") adapter.InsertCommand.Parameters.Add("@Description", _ SqlDbType.Text, 0, "Description") Appendix C - ADO.NET Frequently Asked Questions

adapter.UpdateCommand = New SqlCommand("ap_VideoTapeUpdate", _ New SqlConnection(connectionString))

adapter.UpdateCommand.CommandType = CommandType.StoredProcedure Applied ADO.NET: Building Data-Driven Solutions adapter.UpdateCommand.Parameters.Add _ ISBN:1590590732 by Mahesh Chand and David Talbot ("@VideoTapeID", SqlDbType.Decimal, 0, "VideoTapeID") Apress © 2003 (928 pages) adapter.UpdateCommand.Parameters.Add _ This text provides extensive coverage of ADO.NET technology ("@Title", SqlDbType.Char, 50, "Title") including ADO.NET internals, namespaces, classes, and adapter.UpdateCommand.Parameters.Add _ interfaces, and takes a comprehensive look at XML ("@Description", 0, "Description") namespaces and classes,SqlDbType.Text, and how to integrate both with ADO.NET.

adapter.DeleteCommand = New SqlCommand("ap_VideoTapeDelete", _ New SqlConnection(connectionString)) Table of Contents adapter.SelectCommand.CommandType = CommandType.StoredProcedure Applied ADO.NET—Building Data-Driven Solutions adapter.DeleteCommand.Parameters.Add("@VideoTapeID", _ Introduction SqlDbType.Decimal, 0, "VideoTapeID") Chapter 1

- ADO.NET Basics

Chapter 2

- Data loadAll Components = inNew Visual SqlDataAdapter() Studio .NET

Chapter 3

loadAll.SelectCommand = New SqlCommand("ap_VideoTapeLoadAll", _ - ADO.NET in Disconnected Environments

New SqlConnection(connectionString)) Chapter 4 - ADO.NET in Connected Environments Chapter 5

loadAll.SelectCommand.CommandType = _ - Handling ADO.NET Events

CommandType.StoredProcedure Chapter 6 - Integrating XML with ADO.NET Chapter 7


Chapter 8


Chapter 9


End Sub

Public Function GetVideoTapeByID(ByVal vtID As Decimal) As VideoTape


Dim data As New VideoTapeData() adapter.SelectCommand.Parameters("@VideoTapeID").Value = vtID - Developing a Custom Data Provider adapter.Fill(data) - Developing Database Web Applications ASP.NET If (data.Rows.Count < 1)using Then - Using ADO.NET in Xml Web Services Return Nothing - ASP.NET EndServer If Controls and Data Binding - Building Web Applications DimReal-World vt As New VideoTape(data, 0) - Object-Relational Return vtMapping in .NET Function -End Mapped Objects: Performance Considerations and Data Binding

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 Chapter 14 Chapter 15 Chapter 16 Chapter 17 Chapter 18 Chapter 19

Chapter 20 - COM Interoperability and ADO.NET Chapter 21 -Public MessagingFunction GetAllVideoTapes() As VideoTape()

Dim data As NewNotes VideoTapeData() Chapter 22 - SQL Server and ADO.NET: on Performance loadAll.Fill(data) Appendix A - Relational Databases: Some Basic Concepts Return GetVideoTapeArrayFromData(data) End Function



Public Shared Function GetVideoTapeArrayFromData(ByRef data As VideoTapeData) _ As VideoTape() List of Tables Dim vArray(data.Rows.Count - 1) As VideoTape List of Listings Dim i As Integer List of Sidebars For i = 0 To (data.Rows.Count - 1) vArray(i) = New VideoTape(data, i) Next i Return vArray End Function List of Figures

Public Function SetVideoTape(ByRef vTape As VideoTape) adapter.Update(vTape.MyData) End Function Public Function RemoveVideoTape(ByRef vTape As VideoTape) adapter.DeleteCommand.Parameters("@VideoTapeID").Value = _

vTape.VideoTapeID Applied ADO.NET: Building Data-Driven Solutions adapter.DeleteCommand.Connection.Open() ISBN:1590590732 by Mahesh Chand and David Talbot adapter.DeleteCommand.ExecuteNonQuery() Apress © 2003 (928 pages) adapter.DeleteCommand.Connection.Close() This text provides extensive coverage of ADO.NET technology End Function including ADO.NET internals, namespaces, classes, and End Class interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

The constructor of the VideoTapeDataAccess object initializes the SqlDataAdaptersto use the stored Table of Contents procedures that handle the actual database access. The constructor initializes the Select,Insert,Update, Applied ADO.NET—Building Data-Driven andDelete stored procedures on theSolutions instance called adapter, but only the Select statement on the loadAll Introduction instance. Chapter 1

- ADO.NET Basics

The reason for this is there are ways.NET you want to choose what data to get, but in the end there's only one Chapter 2 - Data Components in multiple Visual Studio way to update it in that database. Both adapters could have been fully initialized, but that would produce a large Chapter 3 - ADO.NET in Disconnected Environments amount of redundant code. By only initializing one adapter for updates, inserts, and deletes, you're avoiding Chapter 4 - ADO.NET in Connected Environments additional code that would needlessly slow down your program. Chapter 5


Chapter 6 - Integrating XMLmethod with ADO.NET TheGetVideoTapeByID gets one VideoTape object out of the database. It sets the @VideoTapeID Chapter 7 Data Binding and Windows Data-Bound Controls parameter on the stored procedure toForms the value passed in and fills the VideoTapeData object with data. If the Chapter database 8 didn't - Constraints find anyand records Data Relations with the VideoTapeID passed in, then it returns Nothing, a null value. If there's

at least9one record returned, it creates Chapter - ADO.NET Exception Handlingan instance of the VideoTape object and initializes it with the data it loaded into the10 VideoTapeData object sets theProvider index to 0 so that the first record retuned is used by the mapped Chapter - Working with the ODBCand .NET Data object. 11 Because the Video-TapeID column is a unique identity column in the database, this stored procedure Chapter - Stored Procedures and Views should 12 never returnSQLXML, more than row. Chapter - Oracle, andone Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

TheGetAllVideoTapes method is much simpler. It creates an instance of the VideoTapeData object and then uses the loadAll SqlDataAdapter to fill it. It then calls the GetVideoTapeArrayFromData method to Chapter - Using ADO.NET Xml Web Services turn the15DataTable into aninarray of VideoTape objects. Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 16 - ASP.NET Server Controls and Data Binding

TheGetVideoTapeArrayFromData method creates an array of VideoTape objects the length of the number Chapter 17 - Building Real-World Web Applications of results from the database loops through the results, creating an instance of the VideoTape Chapter 18 returned - Object-Relational Mapping inand .NET object for row.Objects: As it goes through, it Considerations sets the index and of each object to a different row in the same Chapter 19 each - Mapped Performance DataVideoTape Binding result set. the end it provides the of VideoTape objects to the calling program. Chapter 20 -InCOM Interoperability andarray ADO.NET Chapter 21 - Messaging

The purpose of making the GetVideoTapeArrayFromData a separate method instead of simply putting this code inline with the GetAllVideoTapes method is to provide this method to other objects that may be Appendix A - to Relational Databases: Basic Concepts attempting create instances of Some VideoTape objects. You'll see this put to work later in the Appendix B - Commonly Used SQL Statements VideoCheckInCheckOut object. Chapter 22 - SQL Server and ADO.NET: Notes on Performance


If there are no video tapes in the database, it returns an array with no elements in it, not a null. This is, in general, Index good behavior for a DAC to have when it's expected to return an array of objects. In most situations the calling List of Figures program will want to loop through however many elements are in the array, even if there are no elements. If the List of Tables calling program wants to know if a null was returned, it can always check the length of the array to see if it's zero. List of Listings In the end, returning a zerolength array should simplify your application's code. List of Sidebars TheSetVideoTape object is amazingly short. It simply calls to update the row of the VideoTape object to the database. It automatically selects which stored procedure to call and then executes it with the corresponding data. If it was an insert call, the identity column will be automatically updated in the instance of the VideoTape object. This comes in handy when writing the front-end code of the application. There are many cases where the user will define the data for several related tables on one page, and you'll need a way to know the IDs of the related columns in order to allow the user to edit the data properly. The one-line update call really highlights one of the core ideas of .NET: Hide as much complexity as possible. Your object builds on this principle to hide the rest of the database access functionality in your OR mapped component.

TheRemoveVideoTape method actually uses the Delete command of the adapter directly. You could just ADO.NET: Data-Driven Solutions remove the row inApplied question from the Building VideoTapeData object and then call Update, but doing so could lose the ISBN:1590590732 by Mahesh Chand and David Talbot isolation of the task to be performed. You would have to update the entire VideoTapeData set, which may 2003 (928 pages) include changes Apress that the© calling program doesn't want updated. This ensures that encapsulation is enforced and provides extensive coverage of ADO.NET technology only the row you This wanttext to delete is deleted. including ADO.NET internals, namespaces, classes, and

and a comprehensive lookthe at XML In most cases, it'sinterfaces, a bad idea to takes actually delete rows from database to remove an item from your application. namespaces and classes, and how to integrate both with What you would normally do is have a deleted field on the table that's flagged so you don't have to worry about ADO.NET. maintaining your database's referential integrity or actually losing data. You would also modify your stored procedures that load data into your adapters to not return rows that are flagged as deleted unless it's referred to Table of Contents directly by its primary key. Applied ADO.NET—Building Data-Driven Solutions Introduction

Building the VideoTape Test Case

Chapter 1

- ADO.NET Basics

Chapter 2 - Data Components in Visual It's important to build a test case for anStudio object.NET relationally mapped system. A test case ensures that your Chapter component 3 - ADO.NET does what init's Disconnected supposed to Environments do and ensures that none of your changes have broken existing code. Each

step of 4your test caseinshould say what the expected output is and then show the output so that it's well marked in Chapter - ADO.NET Connected Environments terms of it's supposed to Events do in order to compare the output. It's even possible to build automated test cases Chapter 5 what - Handling ADO.NET that compare these types things automatically, but that's not required for this particular system. Chapter 6 - Integrating XMLofwith ADO.NET Chapter 7


Chapter 8


TheVideoTapeTestCase object will do the following:

1. Load a VideoTape object from the database and display what its data is - ADO.NET Exception Handling

Chapter 9


2. Change the title and description

Chapter 11 - Stored Procedures and Views Chapter 3. Store 12 - Oracle, the object SQLXML, in theand database Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

4. Reload the object and display what its data is

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using Xml Web Services 5. Restore theADO.NET original in VideoTape data and store it Chapter 16 - ASP.NET Server Controls and Data Binding

6. Load all of the VideoTape from the database and show what each one is Chapter 17 - Building Real-World Webobjects Applications Chapter 18 - Object-Relational Mapping in .NET

Listing 18-4 shows the code for the test case.

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter - COM Interoperability and Listing20 18-4: The Test Case for theADO.NET VideoTape Component Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Imports VideoStoreDataModel.EnterpriseVB.VideoStore.Data


Module VideoTapeTestCase

Appendix C - ADO.NET Frequently Asked Questions Index Sub Main() List of Figures Dim vDAC As New VideoTapeDataAccess() List of TablesDim tVTape As VideoTape List of Listings Console.WriteLine("Loading VideoTape") List of Sidebars tVTape` = vDAC.GetVideoTapeByID(1)

Console.WriteLine("VideoTape Loaded:" + tVTape.GetType().ToString()) DisplayVideoTape(tVTape) Dim origTitle = tVTape.Title Dim origDescription = tVTape.Description tVTape.Title = "TestTitle" tVTape.Description = "TestDescription" vDAC.SetVideoTape(tVTape)

tVTape = vDAC.GetVideoTapeByID(1) Applied ADO.NET: _Building Data-Driven Solutions Console.WriteLine ISBN:1590590732 by Mahesh Title=TestTitle Chand and David TalbotDescription=TestDescription") ("After alteration. Apress © 2003 (928 pages) DisplayVideoTape(tVTape) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and tVTape.Title = origTitle interfaces, and takes a comprehensive look at XML tVTape.Description = origDescription namespaces and classes, and how to integrate both with vDAC.SetVideoTape(tVTape) ADO.NET.

tVTape = vDAC.GetVideoTapeByID(1) Console.WriteLine _ Table of Contents ("Restored to origional, should look like the first displayed VideoTape.") Applied ADO.NET—Building Data-Driven Solutions DisplayVideoTape(tVTape) Introduction Chapter 1 Chapter 2

-Console.WriteLine("List ADO.NET Basics all VideoTapes") - Data Components in Visual Studio .NET

Chapter 3

tVideos() As VideoTape -Dim ADO.NET in Disconnected Environments

Chapter 4

vDAC.GetAllVideoTapes() -tVideos ADO.NET in=Connected Environments

Chapter 5


Chapter 6

i As XML Integer -Dim Integrating with ADO.NET

Chapter 7

= 0 and To Windows tVideos.Length - 1 Controls -For Data i Binding Forms Data-Bound

DisplayVideoTape(tVideos(i)) Next Chapter 9 - ADO.NET Exception Handling Console.WriteLine("Press Any Key To Quit...") Chapter 10 - Working with the ODBC .NET Data Provider Console.ReadLine() Chapter 11 - Stored Procedures and Views End Sub Chapter 8



ChapterSub 13 -DisplayVideoTape(ByRef Developing a Custom Data Provider tVTape As VideoTape) Chapter 14 -Console.WriteLine("---------------------------") Developing Database Web Applications using ASP.NET Chapter 15 -Console.WriteLine("VideoTapeID:" Using ADO.NET in Xml Web Services + tVTape.VideoTapeID.ToString()) Chapter 16 -Console.WriteLine("Title:" ASP.NET Server Controls and Data Binding + tVTape.Title) Chapter 17 -Console.WriteLine("Description:" Building Real-World Web Applications + tVTape.Description) ChapterEnd 18 -Sub Object-Relational Mapping in .NET

End Module Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Figure 18-2 shows the VideoTape test case output.


Figure 18-2: TheVideoTape test case output

Using the User AppliedComponent ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

TheUser component and the VideoTape component are virtually identical from the design point of view. The Apress © 2003 (928 pages) core requirements are the same-you want to be able to load one user record or all of them-and the basic data textisprovides extensive coverage technology is to model the people involved with structure of both This objects the same. The purpose of of theADO.NET User component including ADO.NET internals, namespaces, classes, and the application. The User isand thetakes one who can check inlook and at out videos (see Listing 18-5). interfaces, a comprehensive XML namespaces and classes, and how to integrate both with

Listing 18-5: TheADO.NET. User Object in the User Component Imports System Table of Contents Imports System.Data Imports System.Data.SqlClient Introduction Imports System.Data.Common

Applied ADO.NET—Building Data-Driven Solutions Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Namespace EnterpriseVB.VideoStore.Data

ChapterPublic 5 - Handling ADO.NET Class User Events Chapter 6


Chapter 7

-Protected Data Binding and Windows Forms Data-Bound Controls data As DataTable

Chapter 8

-Protected Constraints and Data Relations index As Integer

Chapter 9

- ADO.NET Exception Handling Property MyData() As DataRow() Chapter 10 -Protected Working with Friend the ODBC ReadOnly .NET Data Provider

Get Chapter 11 - Stored Procedures and Views Dim myRow() As DataRow = {Me.data.Rows(index)} Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - DevelopingReturn a CustommyRow Data Provider

End Get Chapter 14 - Developing Database Web Applications using ASP.NET End Property


Public Sub New(ByRef data As UserData, ByVal index As Integer) Me.data = data Chapter 18 - Object-Relational Mapping in .NET Me.index = index Chapter 19 - Mapped Objects: Performance Considerations and Data Binding End Sub Chapter 17 - Building Real-World Web Applications

Chapter 20 - COM Interoperability and ADO.NET Chapter 21 -Public MessagingFunction GetColumn(ByRef ColumnName As String) As Object Chapter 22 - SQL Server anddata.Rows(index)(ColumnName) ADO.NET: Notes on Performance Return Appendix A -End Relational Databases: Some Basic Concepts Function Appendix B - Commonly Used SQL Statements Appendix C -Public ADO.NET Function Frequently Asked SetColumn(ByRef Questions ColumnName As String, _

ByRef ColumnValue As Object) Index List of Figures

data.Rows(index)(ColumnName) = ColumnValue

List of TablesEnd Function List of Listings

Public Property UserID() As Decimal List of Sidebars Get If (GetColumn("UserID").GetType() Is _ Type.GetType("System.DBNull")) Then Return -1 End If Return CType(GetColumn("UserID"), Decimal) End Get Set(ByVal Value As Decimal) SetColumn("UserID", Value) End Set End Property

Public Property FirstName() As String Get Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh"" Chand and David Talbot Return + GetColumn("FirstName") Apress © 2003 (928 pages) End Get This textValue providesAs extensive coverage of ADO.NET technology Set(ByVal String) including ADO.NET internals, namespaces, SetColumn("FirstName", Value) classes, and interfaces, and takes a comprehensive look at XML End Set namespaces and classes, and how to integrate both with End Property ADO.NET. Public Property LastName() As String Table of Contents Get Applied ADO.NET—Building Solutions Return Data-Driven "" + GetColumn("LastName") Introduction End Get Chapter 1 -Set(ByVal ADO.NET Basics Value As String) Chapter 2 - Data SetColumn("LastName", Components in Visual Studio .NET Value) Chapter 3

Set in Disconnected Environments -End ADO.NET

ChapterEnd 4 -Property ADO.NET in Connected Environments Chapter 5


End Class Chapter 6 - Integrating XML with ADO.NET Chapter 7


Chapter 8


Chapter 9


The User object is specifically designed to have as little logic as possible in it. As such, it has simple handling for null values and the ability to use values from the data object.


Chapter 12 - types Oracle, and Other .NET Data in Providers The "verb" ofSQLXML, actions concerning the user relation to the rest of the system belong in the business objects, which you'll see later in the VideoCheckInCheckOut component. Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Listing 18-6 shows the UserData object in the User component.


Chapter - ASP.NET Server Controls Binding Listing16 18-6: The UserData Objectand in Data the User Component Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Public Class UserData Inherits DataTable


Public Sub New() MyBase.New("Users") Appendix A -Me.Columns.Add("UserID", Relational Databases: Some Basic Concepts Type.GetType("System.Decimal")) Appendix B -Me.Columns.Add("FirstName", Commonly Used SQL Statements Type.GetType("System.String")) Appendix C -Me.Columns.Add("LastName", ADO.NET Frequently Asked Questions Type.GetType("System.String")) Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Index List of Figures End Sub List End of Tables Class List of Listings List of Sidebars

TheUserData object defines only three fields in the DataTable: UserID, FirstName, and LastName. Although much more data could be tracked on a user such as addresses and telephone numbers, let's keep it simple. If you want to add this additional functionality, make sure you model it in separate tables. A common mistake beginners make is modeling all of a user's data in one giant table. Some systems go so far as having the person's name, address, phone numbers, credit card information, company, title, and more all in one table. This is bad both from a clean design sense and a performance sense. If a table has too many columns, SQL server handles it slowly. Listing 18-7 shows the UserDataAccess object.

Listing 18-7: The UserDataAccess Object in the User Component Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

Public Class Apress UserDataAccess © 2003 (928 pages) Public connectionString As String This text provides extensive coverage of ADO.NET technology Protected As SqlDataAdapter includingadapter ADO.NET internals, namespaces, classes, and Protected loadAll SqlDataAdapter interfaces, and takesAs a comprehensive look at XML namespaces and classes, and how to integrate both with Public Sub New() ADO.NET. connectionString = "Password=1deadrat;User ID=sa;" + _ "Initial Catalog=VideoStore;Data Source=grimsaado2k;" + _ ID=GRIMSAADO2K;" Table of"Workstation Contents adapter = New SqlDataAdapter() Applied ADO.NET—Building Data-Driven Solutions adapter.SelectCommand = New _ Introduction SqlCommand("ap_UsersLoadByID", New SqlConnection(connectionString)) Chapter 1 - ADO.NET Basics adapter.SelectCommand.CommandType = _ Chapter 2 - Data Components in Visual Studio .NET CommandType.StoredProcedure Chapter 3 - ADO.NET in Disconnected Environments adapter.SelectCommand.CommandType = _ Chapter 4 - ADO.NET in Connected Environments CommandType.StoredProcedure Chapter 5 - Handling ADO.NET Events adapter.SelectCommand.Parameters.Add _ Chapter 6 - Integrating XML with ADO.NET ("@UserID", SqlDbType.Decimal, 0, "UserID") Chapter 7


Chapter 8

- Constraints and Data Relations adapter.InsertCommand = New SqlCommand("ap_UsersInsert", _

Chapter New SqlConnection(connectionString)) 9 - ADO.NET Exception Handling

adapter.InsertCommand.CommandType = _ Chapter 10 - Working with the ODBC .NET Data Provider CommandType.StoredProcedure Chapter 11 - Stored Procedures and Views adapter.InsertCommand.Parameters.Add("@UserID", _ Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers SqlDbType.Decimal, 0, "UserID") Chapter 13 - Developing a Custom Data Provider adapter.InsertCommand.Parameters("@UserID").Direction = _ Chapter 14 - Developing Database Web Applications using ASP.NET ParameterDirection.Output adapter.InsertCommand.Parameters.Add("@FirstName", _ Chapter 16 - ASP.NET Server Controls and Data Binding SqlDbType.Char, 50, "FirstName") Chapter 17 - Building Real-World Web Applications adapter.InsertCommand.Parameters.Add("@LastName", _ Chapter 18 - Object-Relational Mapping in .NET SqlDbType.Text, 0, "LastName") Chapter 19 - Mapped Objects: Performance Considerations and Data Binding adapter.UpdateCommand = New SqlCommand("ap_UsersUpdate", _ Chapter 20 - COM Interoperability and ADO.NET New SqlConnection(connectionString)) Chapter 21 - Messaging adapter.UpdateCommand.CommandType = CommandType.StoredProcedure Chapter 22 - SQL Server and ADO.NET: Notes on Performance adapter.UpdateCommand.Parameters.Add("@UserID", _ Appendix A Relational Databases: Some Basic Concepts SqlDbType.Decimal, 0, "UserID") Appendix B - Commonly Used SQL Statements adapter.UpdateCommand.Parameters.Add("@FirstName", _ Appendix SqlDbType.Char, C - ADO.NET Frequently 50, "FirstName") Asked Questions adapter.UpdateCommand.Parameters.Add("@LastName", _ Index SqlDbType.Text, 0, "LastName") List of Figures Chapter 15 - Using ADO.NET in Xml Web Services

List of Tables

adapter.DeleteCommand = New SqlCommand("ap_UsersDelete", _ New SqlConnection(connectionString)) List of Sidebars List of Listings

adapter.SelectCommand.CommandType = CommandType.StoredProcedure adapter.DeleteCommand.Parameters.Add("@UserID", _ SqlDbType.Decimal, 0, "UserID") loadAll = New SqlDataAdapter() loadAll.SelectCommand = New SqlCommand("ap_UsersLoadAll", _ New SqlConnection(connectionString)) loadAll.SelectCommand.CommandType = _ CommandType.StoredProcedure End Sub

Applied ADO.NET: Building Data-DrivenuserID Solutions Public Function GetUserByID(ByVal As Decimal) As User by Mahesh Chand and David Talbot

ISBN:1590590732

Apress © 2003As (928New pages)UserData() Dim data adapter.SelectCommand.Parameters("@UserID").Value This text provides extensive coverage of ADO.NET technology = userID including ADO.NET internals, namespaces, classes, and adapter.Fill(data) interfaces, and takes a comprehensive look at XML If (data.Rows.Count < 1) Then namespaces and classes, and how to integrate both with Return Nothing ADO.NET. End If Dim vt As New User(data, 0) Table of Contents Return vt Applied ADO.NET—Building Data-Driven Solutions End Function Introduction Chapter 1

GetAllUsers() As User() -Public ADO.NET Function Basics

Chapter 2

data As New Studio UserData() - Data Dim Components in Visual .NET

Chapter 3

loadAll.Fill(data) - ADO.NET in Disconnected Environments

Chapter 4

Dim inuArray(data.Rows.Count) As User - ADO.NET Connected Environments

Chapter 5

DimADO.NET i As Integer - Handling Events

Chapter 6


Chapter 7


Chapter 9


For i = 0 To data.Rows.Count uArray(i) = New User(data, i) Chapter 8 - Constraints and Data Relations Next i Chapter 10 - Working with the ODBC .NET Data Provider

Return uArray

Chapter 11 -End Stored Procedures and Views Function Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 -Public Developing a Custom Data Provider Function SetUser(ByRef user As User) Chapter 14 - Developing Database Web Applications using ASP.NET adapter.Update(user.MyData) Chapter 15 -End UsingFunction ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

FunctionWeb RemoveUser(ByRef user As User) Chapter 17 -Public Building Real-World Applications adapter.DeleteCommand.Parameters("@UserID").Value = user.UserID Chapter 18 - Object-Relational Mapping in .NET adapter.DeleteCommand.Connection.Open() Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM adapter.DeleteCommand.ExecuteNonQuery() Interoperability and ADO.NET

adapter.DeleteCommand.Connection.Close() Chapter 21 - Messaging End Function End Class


End Namespace

Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of DAC Tables The for the User component allows the calling program to look up a single user, list all of the users, update List of Listings or insert a user, or delete a user. Once again the stored procedures are kept simple and the DAC itself is simple. List of Sidebars

Creating the User Test Case TheUser test case will verify that the User component works as expected. It will test your User component by doing the following: 1. Load a user from the database and display what its data is 2. Change the first name and last name 3. Store the object in the database 4. Reload the object and display what its data is 5. 6.

3. 4. 5. Restore the original user data and store it


Mahesh anddatabase David Talbot 6. Load all ofbythe users Chand from the and show whatISBN:1590590732 each one is Apress © 2003 (928 pages)

Listing 18-8 shows the code for the UserTestCase object. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

Listing 18-8: Theinterfaces, UserTestCase Object and takes a comprehensive look at XML


Imports VideoStoreDataModel.EnterpriseVB.VideoStore.Data Table Module of Contents UserTestCase Applied ADO.NET—Building Data-Driven Solutions

Sub Main() Introduction Chapter 1

uDACBasics As New UserDataAccess() -Dim ADO.NET

Chapter 2

As User -Dim Data tUser Components in Visual Studio .NET

Chapter 3

User") -Console.WriteLine("Loading ADO.NET in Disconnected Environments

tUser = uDAC.GetUserByID(1) Console.WriteLine("User Loaded:" + tUser.GetType().ToString()) Chapter 5 - Handling ADO.NET Events DisplayUser(tUser) Chapter 6 - Integrating XML with ADO.NET Dim origFirstName = tUser.FirstName Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Dim origLastName = tUser.LastName Chapter 4


Chapter 8


Chapter 9

-tUser.FirstName ADO.NET Exception Handling = "TestFirst"

Chapter 10 -tUser.LastName Working with the ODBC .NET Data Provider = "TestLast" Chapter 11 - Stored Procedures and Views Chapter 12 -uDAC.SetUser(tUser) Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 -tUser Developing = uDAC.GetUserByID(1) Database Web Applications using ASP.NET

_ Services Chapter 15 -Console.WriteLine Using ADO.NET in Xml Web ("After FirstName=TestFirst LastName=TestLast") Chapter 16 -alteration. ASP.NET Server Controls and Data Binding Chapter 17 -DisplayUser(tUser) Building Real-World Web Applications Chapter 18 -Console.WriteLine Object-Relational Mapping_in .NET

("Restored to origional, should look likeand the Chapter 19 - Mapped Objects: Performance Considerations Datafirst Bindingdisplayed user.") tUser.FirstName = origFirstName tUser.LastName = origLastName Chapter 21 - Messaging uDAC.SetUser(tUser) Chapter 22 - SQL Server and ADO.NET: Notes on Performance tUser = uDAC.GetUserByID(1) Appendix A - Relational Databases: Some Basic Concepts DisplayUser(tUser) Chapter 20 - COM Interoperability and ADO.NET


Appendix C -Console.WriteLine("List ADO.NET Frequently Asked Questions all users") Index List of Figures Dim tUsers() As User List of TablestUsers = uDAC.GetAllUsers() List of Listings List of Sidebars Dim i As Integer

For i = 0 To tUsers.Length - 1 DisplayUser(tUsers(i)) Next Console.WriteLine("Press Any Key To Quit...") Console.ReadLine() End Sub Sub DisplayUser(ByRef tUser As User) Console.WriteLine("UserID:" + tUser.UserID.ToString()) Console.WriteLine("FirstName" + tUser.FirstName) Console.WriteLine("LastName:" + tUser.LastName)

End Sub End Module Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including internals, namespaces, classes, This program ensures thatADO.NET the component works as expected. Youand should run this test case any time you've made interfaces, and takes a comprehensive look at XML changes to the User component to make sure that it still works as expected. Figure 18-3 shows the output of the namespaces and classes, and how to integrate both with UserTestCaseprogram. ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8 - 18-3: Constraints and Data Relations Figure The output of the UserTestCase program Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

Managing Dependencies


Although User component similar to the VideoTape component, it's important to talk about what isn't in the Chapter 13 the - Developing a CustomisData Provider User object. Components that are atApplications the center of yourASP.NET system and relate to a number of other tables should Chapter 14 - Developing Database Web using wherever avoid referencing other components. The other components can reference your core Chapter 15 possible - Using ADO.NET in Xml Web Services

component, but by avoiding the core component referencing narrowly scoped entities such as Check In/Check Out, you can keep your code portable to be used in other projects that don't use Check In Check Out.


Chapter - Object-Relational Mapping in .NETthe video store application. Figure 18 18-4 shows the dependencies within Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List ofFigure Tables 18-4: The dependencies in the video store application List of Listings List of Sidebars

In the design of this application, the Check In/Check Out component has all of the dependencies. You could easily move the VideoTape or User components to their own DLL and use them in other projects with or without each other, and nothing would be broken. The Check In/Check Out component, on the other hand, requires both the User component and VideoTape component. When you're designing your next project, do some careful thinking about what components you plan on being able to use in other projects and think about what you need to do to make sure that core component is as independent as possible. Paranoid Programming In a perfect world, software has a specification that doesn't change, programmers produce the software, and

it's done; there's no need for a second version. In reality, specifications change, goals change, and revisions ADO.NET: Building Data-Driven Solutions happen fasterApplied than you intend. The only way to really manage this risk is what we like to call paranoid ISBN:1590590732 by Mahesh Chand and David Talbot programming. Apress © 2003 (928 pages)

When designing system, imagine usersofmight ask for next and try to anticipate it in your design and This your text provides extensivewhat coverage ADO.NET technology including ADO.NET internals, namespaces, classes, code. If the specification says that each user in the system hasand only one address, design the table schema and and takes a comprehensive look at XML data objects interfaces, to allow a one-to-many relationship because when users change their minds-and they will-it will namespaces and classes, and how to integrate both with be painful to ADO.NET. make an alteration of this type if you did not allow for it in your original design. The hardest part of being a professional programmer is managing expectations and exceeding them. A good will help you manage the S.A.L.E.S. (Say Anything Let Engineering Sweat) part of the equation. Making Table design of Contents sure your core components can easily be added to new projects will help this immensely. Applied ADO.NET—Building Data-Driven Solutions Introduction

To find out what specification for the next version of your product is, check the marketing brochures your sales - ADO.NET Basics team is showing to customers; this should give you a good idea of where the product is headed.

Chapter 1 Chapter 2


Chapter 3


Chapter 4


Chapter 5

- Handling ADO.NET Events Creating the Check In/Check Out Component - Integrating XML with ADO.NET

Chapter 6

Chapter 7 - Data Binding and Forms Data-Bound Controls TheCheck In/Check OutWindows component allows the calling program to do the following: Chapter 8 - Constraints and Data Relations

1. List all of the video tapes currently checked out

Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider 2. Check out a video Chapter 11 - Stored Procedures and Views

3. Check in a video Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

4. Discover the status of a single video


This object at the core ofinyour functionality. The User and VideoTape components hold no real logic, Chapter 15 - is Using ADO.NET Xmlsystem's Web Services but the16 Check In/Check Out component enough to make up the rest of it. Although technically the Chapter - ASP.NET Server Controls and Datahas Binding VideoTape and User objects Web are business objects in that they hold some of the system's logic, the Chapter 17 - Building Real-World Applications CheckInCheckOut object isMapping where the vast majority of the job happens. Chapter 18 - Object-Relational in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Death to N-Tier

Chapter 21 - Messaging Traditional thought is the only way to create a scalable system on the Web is the three-tier model (what Chapter 22 - SQL call Server ADO.NET: on Performance academics the and four-tier modelNotes because they count the browser as a tier). The three-tier model is made up Appendix A Relational Databases: Some Basic Concepts of a Web server, an application server, and a database server. The thinking goes that the code on your Web Appendix B - Commonly Used SQL Hypertext StatementsMarkup Language (HTML) generation and an interface back to the servers should only provide Appendix C - ADO.NET Frequently Asked Questions application server, which is actually running the code with the business logic in it. Of course, behind that is the Indexdatabase server, which should be treated as a dumb repository of data with no logic in it whatsoever

on the server you purchased, this may be a more truthful statement than with others). List of(depending Figures List of Tables

The three-tier model has a number of problems, though. Every layer you add increases the likelihood of down time. If your application server cluster goes down, then your whole application will cease to function. Also, List of Sidebars every incoming request goes from the Web server to the database server and on to the database server-and of course back again. The extra layer increases latency and adds to the complexity of your application. Complexity is inherently evil and must be destroyed; therefore, the physical two-tier model and logical threetier model were born. List of Listings

Under the 2/3 model, the database stays a dumb place where your data is stored, but the business logic objects live on the Web server. We're not saying your business logic should go in your code behind-far from it. What we're saying is that the data objects and logic objects you're creating in this chapter should live in nice, neat, compiled DLLs that your ASPX pages access. This reduces latency as network usage goes down, this reduces complexity because you've cut a layer out of your application, and this significantly reduces the total cost of deploying your application.


ISBN:1590590732

TheCheckInCheckOut looks Apress © object 2003 (928 pages)quite a bit like a function library and less like a real object. The reason is simple; this component defines the actions you're taking on the video tapes and users. By isolating the types of This text provides extensive coverage of ADO.NET technology actions that can be taken with users and video tapes inside this object, including ADO.NET internals, namespaces, classes, and the .aspx pages that use this business a comprehensive at XML object layer haveinterfaces, the ability and to dotakes amazing things in justlook a few lines of code: namespaces and classes, and how to integrate both with ADO.NET.

VideosCheckedOutDataGrid.DataSource = (New _ VideoCheckInCheckOut(conn)). _ Table of Contents GetVideoTapesCheckedOutToUser(user) Applied ADO.NET—Building Data-Driven Solutions Introduction

This example shows how the VideoCheckInCheckOut component allows everything that's currently checked Chapter 1 - ADO.NET Basics

out to a single person to be listed in an .aspx page in one line of code. This truly comes in handy when you've got - Data Components in Visual Studio .NET 20 different pages listing the videos checked out to a single user and the need arises to alter the actual logic Chapter 3 - ADO.NET in Disconnected Environments behind it. One scenario where this might happen is if the checkout process allowed the user to choose how many Chapter 4 - ADO.NET in Connected Environments days they wanted to pay for when they checked out the video. This would involve altering the data model and the Chapter 5 - Handling ADO.NET Events logic concerning the data model, especially if a "list overdue" videos feature was added that would include even Chapter 6 - Integrating XML with ADO.NET more dependant logic than just a simple check in/check out. Chapter 2

Chapter 7


Chapter 8 -embedded Constraintsthe and Data Relations If you had call to a stored procedure directly into your page as you probably would have under the Chapter ASP model, 9 - ADO.NET you would Exception have quite Handling a task ahead of you! You would have to go to each page and add the handling

for the 10 new- Working field nowwith being from theProvider stored procedure and take proper action on it to handle it. Obviously, Chapter thereturned ODBC .NET Data this is a11 situation toProcedures avoid. Chapter - Stored and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

In the VideoCheckInCheckOut object, you'll notice a few things that are poorly coded in terms of good objectoriented principles, so be prepared. There's a conflict between good and fast under this model. You can have your Chapter 14 - Developing Database Web Applications using ASP.NET code 90 percent well designed and easy to maintain, but sometimes you just have to break it a little to get the kind Chapter 15 - Using ADO.NET in Xml Web Services of performance you need. Chapter 13 - Developing a Custom Data Provider


Seeing How It Works

Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and fairly Data simple. Binding The design goal of this component is to TheVideoCheckInCheckOut component's workings are Chapter 20 COM Interoperability and ADO.NET provide the ability to check out a video tape to a user, check it back in, and be able to determine the state of this Chapter 21 - Messaging information in a few ways. Chapter 22 - SQL Server and ADO.NET: Notes on Performance

When a Arow is inserted into the VideoCheckOut table, a new VideoCheckOutIDis "automagically" generated Appendix - Relational Databases: Some Basic Concepts by SQL B Server. The VideoCheckIn table has a VideoCheckOutID that references this ID. Anytime there's a Appendix - Commonly Used SQL Statements VideoCheckOutID in the VideoCheckOut table that's not in the VideoCheckIn table, a video is currently Appendix C - ADO.NET Frequently Asked Questions checked out. Index List of Figures

You can apply a few strategies on this data to determine if a video tape is checked out; you'll learn about this in the

List of section, Tables which is about the design of the Check In/Check Out components. next List of Listings List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions Making Design Tradeoffs by Mahesh Chand and David Talbot

ISBN:1590590732

There are three main tradeoffs to pages) look at between good and fast design. Depending on the requirements for Apress © 2003 (928 your application you'll have to make decisions on eachofofADO.NET these items and evaluate the kinds of risks doing This text provides extensive coverage technology it the fast way pose to the design of your system. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces classes, andhas howato integrate with The seemingly innocent codeand in Listing 18-9 number of both implications you must be aware of when ADO.NET. working with OR mapping in a system such as the video store application.

Listing 18-9: SelectVideosCheckedOutToUser

Table of Contents


CREATE PROCEDURE dbo.SelectVideosCheckedOutToUser Introduction @UserID -decimal ADO.NET Basics AS Chapter 2 - Data Components in Visual Studio .NET BEGIN Chapter 3 - ADO.NET in Disconnected Environments SELECT VideoTapeID, Title, Description FROM VideoTape WHERE Chapter 4 - ADO.NET in Connected Environments VideoTapeID IN Chapter 5 - Handling ADO.NET Events ( Chapter 6 VideoTapeID - Integrating XMLFROM with ADO.NET SELECT VideoCheckOut as vco WHERE Chapter 7 Data Binding and Windows AND FormsVideoTapeID Data-Bound Controls CheckedOutToUserID=@UserID NOT IN Chapter 8 -VideoTapeID Constraints and Data (SELECT FromRelations VideoCheckIn as vci WHERE Chapter 9 - ADO.NET Exception Handling vco.VideoCheckOutID=vci.VideoCheckOutID) Chapter 10 - Working with the ODBC .NET Data Provider ) Chapter END 11 - Stored Procedures and Views Chapter 1

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Understanding Logic in Stored Procedures


Chapter 17possible - Building Real-World Web anything Applications The first tradeoff is having resembling logic in your stored procedures. In the SelectVideosCheckedOutToUser Chapter 18 - Object-Relational Mapping in stored .NET procedure, a nested subquery finds out what VideoCheckOut

entries 19 don't have VideoCheckIn entries. An alternateand approach to this is to load all VideoCheckOut Chapter - Mapped Objects: Performance Considerations Data Binding entries 20 andall VideoCheckIn using simple stored procedures, then make this comparison in your Chapter COM Interoperability entries and ADO.NET VB .NET Chapter 21code. - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

The advantage of using the stored procedure in Listing 18-9 is a much faster response time with only a small amount of data traveling over your network. Because the results are being filtered by the database Appendix B - Commonly Used SQL Statements server, only the small chunk of data you're looking for will be returned. Appendix A - Relational Databases: Some Basic Concepts Appendix C - ADO.NET Frequently Asked Questions

Index The disadvantage of placing this type of logic in a stored procedure is the maintainability of your code and

theofcost/scalability of your database server. When another programmer comes along and wants to alter the List Figures behavior of what the definition of CheckedOut is within your system, they'll have to trace your objects all List of Tables theofway back to the stored procedures to find out how you did this. List Listings List of Sidebars

Another disadvantage is that your database is a finite resource. Running Microsoft SQL Server 2000 on .NET Server, you can cluster a maximum of eight machines together at an unbelievable hardware/software cost. Every bit of logic you have your stored procedures apply takes more resources from these machines. On the other hand, you can add Web servers almost indefinitely using a number of solutions available in the marketplace for a minimal cost (in comparison to expanding the database). The other point of balance is large chunks of data. If the data to be returned is potentially large, it could be more of a burden on your database servers overall than having just sorted through it on its own. It'll take some time and thinking as to whether it's more database intensive one way or another. In the video store application, for example, most people in the system of an average video store have checked out more than 100 tapes but only have two checked out at a time. Some people have checked out more than 1,000, and returning all 2,000 (1,000 from the VideoCheckIn table and 1,000 from the VideoCheckOut table) could

cause serious stress on the database server and the network.


Understanding Component Isolation Apress © 2003 (928 pages)

ISBN:1590590732


The next problemincluding with the ADO.NET stored procedure in Listing 18-9 is the co-mingling of components. Notice how internals, namespaces, classes, and the stored procedure returns not only the VideoTapeID, the Title and Description as well? This interfaces, and takes a comprehensive look but at XML means that if an alteration is made to the and VideoTape component's data model, the namespaces and classes, how to integrate both with ADO.NET. object will require reworking. VideoCheckInCheckOut The only advantage of returning the data in line is speed. If only the was returned, then the calling program

Table of likely Contents would make a separate call to the VideoTapeDataAccess object's GetVideoTapeByID, each in turn Applied ADO.NET—Building Data-Driven calling a stored procedure on its own Solutions to get the VideoTape referenced by the returned ID. By returning the Introduction data inline you're removing the need for the calling program to make separate round trips to the database. Chapter 1 - ADO.NET Basics

The disadvantage of returninginthe dataStudio in line.NET is that changes in your VideoTape component will likely Chapter 2 - Data Components Visual break the component. If you add a field to the VideoTape object such as Chapter 3 VideoCheckInCheckOut - ADO.NET in Disconnected Environments

YearReleased, you must alter the VideoCheckInCheckOut object and stored procedure as well. If - ADO.NET in Connected Environments these types of interdependencies are not well documented, you're well on your way to creating an Chapter 5 - Handling ADO.NET Events unmaintainable system. Chapter 4 Chapter 6


Chapter 7 -design Data Binding anditWindows Forms Data-Bound Controls The good way to do is to have the stored procedure only return VideoTapeIDs and then leave the Chapter 8 - Constraints Relations job of turning these IDsand intoData objects in the VideoTape component's court. Chapter 9

- ADO.NET Exception Handling If you employ a technique likeODBC this in your system, make sure that it's well documented within the Chapter 10 - Working with the .NET Data Provider

VideoTape and the VideoCheckInCheckOut components. Both sides that are engaging in naughty Chapter 11 - Stored Procedures and Views behavior to have a lineand drawn between them not only to let future programmers that come after you Chapter 12need - Oracle, SQLXML, Other .NET Data Providers know what you've done, but also to help you keep track of what you've done.



Creating a Workaround on Part of the Problem



The component isolation part of the speed vs. design problem has a partial solution. You can take the specifics of turning the results of your VideoCheckInCheckOut stored procedure from data into objects Chapter 18 - Object-Relational Mapping in .NET and place it squarely on the shoulders of your VideoTape component. By designing the VideoTape Chapter 19 - Mapped Objects: Performance Considerations and Data Binding component to include public methods for transforming VideoTapeData objects into VideoTape objects, Chapter 20 - COM Interoperability and ADO.NET you can bank on ADO.NET's SqlDataAdapter's ability to map the results of a stored procedure to fields Chapter 21 - Messaging in an ADO.NET DataSet.Listing 18-10 shows the VideoCheckInCheckOut object, found in Chapter 22 - SQL Server and ADO.NET: Notes on Performance ObjectRelationalMappingVB/VideoStoreDataModel/VideoCheckInCheckOut.vb. Chapter 17 - Building Real-World Web Applications


Listing 18-10: The VideoCheckInCheckOut Object Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index

Public Function GetVideoTapesCheckedOutToUser(ByRef usr As User) _

List Figures AsofVideoTape() List of Tables

Dim cmd As New SqlDataAdapter("ap_SelectVideosCheckedOutToUser", _

List of Listings New SqlConnection(connectionString)) List of Sidebars

cmd.SelectCommand.CommandType = CommandType.StoredProcedure cmd.SelectCommand.Parameters.Add("@UserID", _ SqlDbType.Decimal) cmd.SelectCommand.Parameters("@UserID").Value = usr.UserID Dim data As VideoTapeData cmd.Fill(data) Return VideoTapeDataAccess.GetVideoTapeArrayFromData(data) End Function

In the GetVideoTapesCheckedOutToUser method, you use the VideoTapeData object to fill the

result set and use the GetVideoTapeArrayFromData method on the VideoTapeDataAccess object Applied ADO.NET: Buildingobjects. Data-Driven Solutions to turn this data into an array of VideoTape This means that any alterations made to the structure ISBN:1590590732 by Mahesh Chand and David Talbot of the VideoTape table in the database will require fixing only the VideoTape component's code, not the Apress © 2003 (928 pages) VideoCheckInCheckOut component's code. The stored procedure that the VideoCheckInCheckOut This text provides coverage of ADO.NET technology component is using will still have toextensive be altered to ensure it includes the new fields, but if you're careful in including ADO.NET internals, namespaces, classes, and documenting your dependencies this should make it manageable (see Listing 18-11). interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Listing 18-11: The VideoCheckInCheckOut Object ADO.NET.

Public Class VideoCheckInCheckOut Private connectionString As String

Table of Contents


Public Sub New(ByVal connStr As String)

Chapter 2

- ADO.NET Basics Me.connectionString = connStr -End Data Sub Components in Visual Studio .NET

Chapter 3


Chapter 4

-Public ADO.NET Function in ConnectedGetVideoTapesCheckedOutToUser(ByRef Environments usr As User) _

Chapter 5 - Handling ADO.NET Events As VideoTape() Chapter 6

- Integrating Dim cmd XML with As New ADO.NET SqlDataAdapter("ap_SelectVideosCheckedOutToUser", _

New SqlConnection(connectionString)) Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Chapter 8

cmd.SelectCommand.CommandType = CommandType.StoredProcedure - Constraints and Data Relations

cmd.SelectCommand.Parameters.Add("@UserID", _ - ADO.NET Exception Handling SqlDbType.Decimal) Chapter 10 - Working with the ODBC .NET Data Provider cmd.SelectCommand.Parameters("@UserID").Value = _ Chapter 11 - Stored Procedures and Views usr.UserID Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Dim data As New VideoTapeData() Chapter 13 - Developing a Custom Data Provider cmd.Fill(data) Chapter 14 - Developing Database Web Applications using ASP.NET Return VideoTapeDataAccess.GetVideoTapeArrayFromData(data) Chapter 15 - Using ADO.NET in Xml Web Services End Function Chapter 9


Chapter 17 -Public Building Real-World Applications FunctionWeb GetVideoTapesCheckedIn() As VideoTape() Chapter 18 - Object-Relational Mapping .NET Dim cmd As New in SqlDataAdapter("ap_SelectVideosCheckedIn", _ Chapter 19 - Mapped Objects: Performance Considerations and Data Binding New SqlConnection(connectionString)) Chapter 20 - COM cmd.SelectCommand.CommandType Interoperability and ADO.NET = CommandType.StoredProcedure Chapter 21 - Messaging Dim data As New VideoTapeData() Chapter 22 - SQL Server cmd.Fill(data) and ADO.NET: Notes on Performance

Return VideoTapeDataAccess.GetVideoTapeArrayFromData(data) Appendix A - Relational Databases: Some Basic Concepts Function Appendix B -End Commonly Used SQL Statements CheckOutVideoToUser(ByRef usr As User, _ Appendix C -Public ADO.NET Function Frequently Asked Questions ByRef toUsr As User, ByRef vt As VideoTape) Index If (Me.IsVideoCheckedOut(vt)) Then Throw New Exception("Video is already checked out to another user.") List of Tables End If List of Listings Dim cmd As New SqlCommand("ap_CheckOutVideo", _ List of Sidebars New SqlConnection(connectionString cmd.CommandType = CommandType.StoredProcedure cmd.Parameters.Add("@CheckedOutByUserID", _ SqlDbType.Decimal) cmd.Parameters.Add("@CheckedOutToUserID", _ SqlDbType.Decimal) cmd.Parameters.Add("@VideoTapeID", _ SqlDbType.Decimal) cmd.Parameters("@CheckedOutToUserID").Value = _ usr.UserID cmd.Parameters("@CheckedOutByUserID").Value = _ toUsr.UserID List of Figures

cmd.Parameters("@VideoTapeID").Value = _ Applied ADO.NET: Building Data-Driven Solutions vt.VideoTapeID ISBN:1590590732 by Mahesh Chand and David Talbot cmd.Connection.Open() Apress © 2003 (928 pages) cmd.ExecuteNonQuery() This text provides extensive coverage of ADO.NET technology cmd.Connection.Close() including ADO.NET internals, namespaces, classes, and End Function

interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Public Function CheckInVideoFromUser(ByRef usr As User, _ ADO.NET.

ByRef vt As VideoTape) Dim cmd As New SqlCommand("ap_CheckInVideo", _ Table Contents New ofSqlConnection(connectionString)) Applied ADO.NET—Building Data-Driven Solutions cmd.CommandType = CommandType.StoredProcedure Introduction cmd.Parameters.Add("@UserID", _ Chapter 1 - ADO.NET Basics SqlDbType.Decimal) Chapter 2 - Data cmd.Parameters.Add("@VideoTapeID", Components in Visual Studio .NET _ SqlDbType.Decimal) Chapter 3 - ADO.NET in Disconnected Environments cmd.Parameters("@UserID").Value = usr.UserID Chapter 4 - ADO.NET in Connected Environments cmd.Parameters("@VideoTapeID").Value = _ Chapter 5 - Handling ADO.NET Events vt.VideoTapeID Chapter 6 - Integrating XML with ADO.NET Chapter 7 - Data cmd.Connection.Open() Binding and Windows Forms Data-Bound Controls cmd.ExecuteNonQuery() Chapter 8 - Constraints and Data Relations cmd.Connection.Close() Chapter 9 - ADO.NET Exception Handling End Function Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

Public Function IsVideoCheckedOut(ByRef vt As VideoTape) As Boolean Dim cmd As New SqlCommand("ap_IsVideoCheckedOut", _ Chapter 13 - Developing a Custom Data Provider New SqlConnection(connectionString)) Chapter 14 - Developing Database Web Applications using ASP.NET cmd.CommandType = CommandType.StoredProcedure Chapter 15 - Usingcmd.Parameters.Add("@VideoTapeID", ADO.NET in Xml Web Services _ Chapter 16 - ASP.NET Server Controls and Data Binding SqlDbType.Decimal) Chapter 17 - Building Real-World Web Applications cmd.Parameters("@VideoTapeID").Value = _ Chapter vt.VideoTapeID 18 - Object-Relational Mapping in .NET cmd.Connection.Open() Chapter 19 - Mapped Objects: Performance Considerations and Data Binding isCheckedOut As Boolean Chapter 20 - COM Dim Interoperability and ADO.NET isCheckedOut = cmd.ExecuteScalar() Chapter 21 - Messaging cmd.Connection.Close() Chapter 22 - SQL Server and ADO.NET: Notes on Performance Return isCheckedOut Appendix A - Relational Databases: Some Basic Concepts End Function Appendix B - Commonly Used SQL Statements End Class Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Appendix C - ADO.NET Frequently Asked Questions Index List of Figures

List of Tables In the VideoCheckInCheckOut object you're modeling all of your "verbs." Each method of this object List of Listings actually performs an action or describes a state as opposed to just returning data. List of Sidebars

The two workhorses of this object are CheckInVideoFromUser and CheckOutVideoToUser. Each is a thin wrapper around calling a stored procedure but provides an important spot where future business logic can be added. If, for example, you chose to add accounting functionality to the system, it would be a simple matter of adding calls that code at this location. Under that scenario, you would not need to change any of your front-end code to work with these enhancements to your system.

Creating the VideoCheckInCheckOut Test Case To properly test the VideoCheckInCheckOut component, you'll need to do the following: 1. 2.

1. Check a video to see if it's checked out


Mahesh Chand and David Talbot 2. Check outby a video

ISBN:1590590732


3. Check theThis video's text status provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

4. List all checked out videos for the user interfaces, and takes a comprehensive look at XML


5. List all theADO.NET. videos that are not checked out to anyone 6. Check in the video Table of Contents

7. ADO.NET—Building Check the status of the video Solutions Applied Data-Driven Introduction

8. List all the videos checked out to the user

Chapter 1

- ADO.NET Basics

Chapter 2 -all Data in Visual Studio .NET 9. List theComponents videos that are not checked out to anyone Chapter 3 - ADO.NET in Disconnected Environments

As you 4can- ADO.NET see, this test case is quite a bit more complicated than the test case for the User and Chapter in Connected Environments

VideoTape components! It's not enough to just test each method once; you have to verify that the listing - Handling ADO.NET Events methods actually get the right data when the video's state is displayed. Listing 18-12 shows the test case for Chapter 6 - Integrating XML with ADO.NET theVideoCheckInCheckOut component. Chapter 5 Chapter 7


Chapter - Constraints and Datafor Relations Listing818-12: The Test Case the VideoCheckInCheckOut Component Chapter 9






Module VideoCheckInCheckOutTestCase

Chapter 13 - Developing a Custom Data Provider ChapterSub 14 -Main() Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 -Dim ASP.NET Server and Data Binding vDAC As Controls New VideoTapeDataAccess() Chapter 17 -Dim Building Real-World Web Applications uDAC As New UserDataAccess() Chapter 18 -Dim Object-Relational vciDAC AsMapping New VideoCheckInCheckOut(vDac.connectionString) in .NET

tTape As Performance VideoTapeConsiderations and Data Binding Chapter 19 -Dim Mapped Objects: = vDAC.GetVideoTapeByID(1) Chapter 20 -tTape COM Interoperability and ADO.NET Tape Checked Out:" + _ Chapter 21 -Console.WriteLine("Is Messaging vciDAC.IsVideoCheckedOut(tTape).ToString()) Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Dim tUser As User tUser = uDAC.GetUserByID(1) Appendix C - ADO.NET Frequently Asked Questions Console.WriteLine("Checking out video.") Index vciDAC.CheckOutVideoToUser(tUser, tUser, tTape) List of Figures Console.WriteLine("Is Tape Checked Out:" + _ List of Tables vciDAC.IsVideoCheckedOut(tTape).ToString()) Appendix B - Commonly Used SQL Statements

List of Listings List of Sidebars Dim tapes() As VideoTape

tapes = vciDAC.GetVideoTapesCheckedOutToUser(tUser) Console.WriteLine("Tapes Currently Checked Out To User:") DisplayTapeArray(tapes) Console.WriteLine("Tapes Not Currently Checked Out To Anyone") tapes = vciDAC.GetVideoTapesCheckedIn() DisplayTapeArray(tapes) vciDAC.CheckInVideoFromUser(tUser, tTape) Console.WriteLine("Video Checked In") Console.WriteLine("Is Tape Checked Out:" + _

vciDAC.IsVideoCheckedOut(tTape).ToString()) Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Chand and David Talbot tapesby =Mahesh vciDAC.GetVideoTapesCheckedOutToUser(tUser)

Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology Console.WriteLine("Tapes Currently Checked Out To User:") including ADO.NET internals, namespaces, classes, and DisplayTapeArray(tapes) interfaces, and takes a comprehensive look at XML Console.WriteLine("Tapes Not toCurrently Checked Out To Anyone") namespaces and classes, and how integrate both with tapesADO.NET. = vciDAC.GetVideoTapesCheckedIn() DisplayTapeArray(tapes) Table of Contents Console.WriteLine("Press Any Key To Quit...") Applied ADO.NET—Building Data-Driven Solutions Console.ReadLine() Introduction End Sub ChapterSub 1 -DisplayTapeArray(ByRef ADO.NET Basics tapes() As VideoTape) Chapter 2 -Dim Data i Components As Integer in Visual Studio .NET Chapter 3

i = in0Disconnected To tapes.Length - 1 -For ADO.NET Environments

Chapter 4

Console.WriteLine("TAPE:" + tapes(i).Title) - ADO.NET in Connected Environments

Chapter 5

-Next Handling ADO.NET Events

ChapterEnd 6 -Sub Integrating XML with ADO.NET

End Module Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Chapter 8


Chapter 9



The test case correctly exercises each of the methods provided by the VideoCheckInCheckOut

Chapter 11 - Stored Procedures and Views component. There's a caveat here, though; if the video (VideoTapeID 1) is already checked out, an Chapter 12 Oracle, SQLXML, and Othershows .NET Data Providers exception will be thrown. Figure 18-5 the output of CheckInCheckOut test case. Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - 18-5: ADO.NET Asked Questions Figure TheFrequently output of the CheckInCheckOut test case Index List of Figures List of Tables List of Listings List of Sidebars

Summary


ISBN:1590590732

OR mapping affords the©ability to hide Apress 2003 (928 pages)data access completely from your application and greatly simplify the front-end code you write for your application. It allows you to write all of your data access logic once This text provides extensive coverage of ADO.NET technology and allows significantly increased flexibility in your system. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces classes, andthese how to integrate both with In the next chapter, you'll lookand at how to use mapped objects with ASP.NET widgets such as ADO.NET. DataGrids. You'll also look at some additions to the performance end of your data model and implement a high-performance caching mechanism. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 19: Mapped Objects: Performance ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) Considerations and Data Binding This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with In the last chapterADO.NET. you learned the basics of turning the data in your database into objects. Although basic

Overview

Object-Relational (OR) mapping is simple, a number of issues become apparent when it comes time to actually put it to work. Table of Contents Applied In this ADO.NET—Building chapter you'll learnData-Driven how to put Solutions your objects to work in ASP.NET using data binding and how to solve Introduction the problems posed in relationships by working with master-detail relationships and building a tree Chapter 1 for - ADO.NET Basics structure performance. Chapter 2 - Data Components in Visual Studio .NET

The chapter also covers how to implement a simple, near-zero-impact caching scheme for your objects Chapter 3 - ADO.NET in Disconnected Environments and how business objects to further abstract your mapped objects. Chapter 4 to- create ADO.NET in Connected Environments Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


These topics should help you solve common problems encountered when using OR mapping.


ADO.NET: Data-Driven Solutions Using DataApplied Binding andBuilding Mapped Objects by Mahesh Chand and David Talbot

ISBN:1590590732

To get real use out of your mapped objects, you have to know how to leverage them with .NET's many server-side Apress © 2003 (928 pages) ASP.NET controls. The overall methodology of using of data bindingtechnology with mapped objects is similar to the technique This text provides extensive coverage ADO.NET you can use on aincluding DataSet or DataTable yet it affords much greater ADO.NET internals, namespaces, classes, and flexibility. interfaces, and takes a comprehensive look at XML

You can bind all of namespaces the .NET controls and classes, that and allow how data to integrate binding toboth anywith object that implements IEnumerable. Don't ADO.NET. panic, you don't have to actually implement IEnumerable and create custom collections for each group of mapped objects. Instead, Microsoft was kind enough to do that for you by implementing IEnumerable in all of their collections from ArrayList to Hashtable.

Table of Contents

Applied ADO.NET—Building Data-Driven Solutions The ability to bind to virtually any .NET collection is liberating when you think about it. For example, if you store a Introduction number of objects in a Hashtable, you can actually bind it to a DataGrid control, work with the data, and then Chapter - ADO.NET Basics writing very little code. The advantage this affords you is the ability to enforce store it 1back in the database Chapter 2 logic - Data Visual Studio .NET business in Components your objects in while providing the ease of use of .NET data binding. Chapter 3


Chapter 4

Using Connection Strings - ADO.NET in Connected Environments

Chapter 5


The examples in the previous chapter and in this one use hard-coded database connection strings. This is - Integrating XML with ADO.NET something you should never do in a real application because you would have to recompile your program every Chapter 7 - Data Binding and Windows Forms Data-Bound Controls time your application runs in a place where the database is different. Chapter 6 Chapter 8


Chapter - ADO.NET Exception Handling In a9 practical application this is generally the difference between your development environment and Chapter 10 - Working with the ODBC .NETit's Data Provider production environment. Granted, easy for you to change the connection string and then recompile and Chapter copy 11 your - Stored files Procedures over if you're andworking Views in a small company. The problem is that your application will slowly start

gaining more deployment-specific data Data in theProviders code over time, and it will become difficult to maintain to say the Chapter 12 - Oracle, SQLXML, and Other .NET least-not to mention you'll likely forget to change it every time you get ready to deploy. So, it's generally a Chapter 13 - Developing a that Custom Data Provider good to get it right the first and put what gives you to use with the web.config file. Chapter 14 idea - Developing Database Webtime Applications using.NET ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Web Applications The code-behind fileReal-World of the TestDataGrid program highlights one of the advantages of OR mapping (see Listing Chapter 18 - amount Object-Relational Mapping in .NET 19-1). The of code you actually have to write is limited to just a few lines that list the contents of the Chapter 19 - database. Mapped Objects: Performance Considerations and Data Binding VideoTape Chapter 20 - COM Interoperability and ADO.NET

Listing21 19-1: The Code-Behind File of the TestDataGrid Program Chapter - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A -VideoStoreDataModel.EnterpriseVB.VideoStore.Data Relational Databases: Some Basic Concepts Imports Appendix B - Commonly Used SQL Statements Appendix PublicC Class - ADO.NET WebForm1 Frequently Asked Questions Index Inherits System.Web.UI.Page

Protected WithEvents VideoTapesGrid As System.Web.UI.WebControls.DataGrid List of Figures List of Tables

Private Sub Page_Load(ByVal sender As System.Object, _ List of Listings ByVal e As System.EventArgs) _ List of Sidebars Handles MyBase.Load Dim dac As New VideoTapeDataAccess() VideoTapesGrid.DataSource = dac.GetAllVideoTapes() If (Not IsPostBack) Then VideoTapesGrid.DataBind() End If End Sub End Class

In the Page_Load method, first you create an instance of the VideoTapeDataAccess Data Access Component ADO.NET: Building Data-Driven Solutions (DAC). Next, youApplied set the DataSource of the VideoTapesGrid to the array of VideoTape objects returned ISBN:1590590732 DAC. Finally, if the page request being by Mahesh Chand and David Talbot from the GetAllVideoTapes() method of the VideoTapeDataAccess Apress © 2003 (928 pages) served is not a postback, you call the DataBind method to update the User Interface (UI) of the This text provides VideoTapesGrid DataGrid. extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML as simple as the code-behind file using the The Hypertext Markup Language (HTML) side of this page is just namespaces and classes, and how to integrate both with syntax identical toADO.NET. the way you would bind to a DataSet or DataTable (see Listing 19-2).

Listing 19-2: The HTML Side of the TestDataGrid Page Table of Contents Applied ADO.NET—Building Data-Driven Solutions Chapter 1 - ADO.NET Basics Chapter 2


Chapter 3

- ADO.NET in Disconnected Environments Chapter 4 - ADO.NET in Connected Environments

name="GENERATOR" Chapter name="CODE_LANGUAGE" content="Visual Basic 7.0"> Chapter Chapter deepest) Then Chapter 21 - Messaging = tDepth Chapter 22 - SQL Serverdeepest and ADO.NET: Notes on Performance End Databases: If Appendix A - Relational Some Basic Concepts Next Return deepest Appendix C - ADO.NET Frequently Asked Questions End Function Index End Class Appendix B - Commonly Used SQL Statements


List of Listings List of can Sidebars You break the code-behind object of the LazyLoading page into two primary functional parts: the tree

rendering portion and the VideoTape listing. TheDisplayCategoryTree() method delegates the task of building the table to RenderTree() and GetDepth() methods after loading the data from the database. The GetDepth() method is needed so you know how deep the deepest element is in the tree to determine what the ColSpan needs to be for each category to achieve a nice tabbed look for the tree. As the tree is being rendered, it checks each VideoCategory to see if it matches the SelectedCategoryID property. If it does, it highlights that category. At the end of the DisplayCategoryTree() method, it checks to see if SelectedCategoryID has a value provided. If it does, the program makes a call to the FindCategoryByID() method of the VideoCategory object to get the category that the user has selected. It then sets the DataSource of the VideoTapesGrid to the Videos array of the VideoCategory object and calls DataBind() to update the display.

As the Videos array is accessed forBuilding the first time, behind the scenes the VideoCategory object loads the array Applied ADO.NET: Data-Driven Solutions ofVideoTapes from the database and returns it. Subsequent attempts to the Videos collection of the ISBN:1590590732 by Mahesh Chand and David Talbot VideoCategoryApress object© will use the version already in memory without having to make another round trip to the 2003 (928 pages) database.Figure This 19-8text shows the LazyLoading page in action. provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - 19-8: Working with the ODBC Data Provider Figure The output of the.NET LazyLoading page Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Implementing an Incremental Lazy Loading Scheme



Lazy loading as described section works for most purposes, but if you're in a situation where the Chapter 15 - Using ADO.NET in in the Xmlprevious Web Services detail set potentially hundreds or thousands of records, then it becomes necessary to implement an incremental Chapter 16 is - ASP.NET Server Controls and Data Binding lazy loading technique. Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

In a nutshell, when the information is first requested from the detail set, a small number of records will be retrieved along with the count of the total number of records. If a request is made for one of the records that's out of range Chapter - COM Interoperability andrecords ADO.NET of what20 was loaded, the rest of the will be loaded. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 21 - Messaging

An example of where useful on a "summary page" that displays the first 10 records on the front Chapter 22 - SQL Serverthis andtechnique ADO.NET:isNotes onisPerformance page and the user to click Some for more information. Appendix A allows - Relational Databases: Basic Concepts Most of the time the user will not click the link to see the additional so itUsed doesn't any sense to load them and incur the network overhead between your Web Appendix B -records, Commonly SQLmake Statements server and to fetch theAsked entireQuestions result set if it's not necessary. Appendix C - database ADO.NET Frequently Index

To implement the incremental lazy loading scheme, you must modify both the stored procedure and the

List of Figures VideoCategory component. The VideoCategory object needs to get the first 10 records from the database, List of and itTables also needs to know how many records there are total in the database, so the VideoCategory object will List of Listings know if and when an additional round trip to the database is necessary. Listing 19-12 shows the List of Sidebars VideoTapeLoadByCategoryIncrID stored procedure, which loads the first 10 video tapes for a given

category. Listing 19-12: The Incremental Lazy Loading Stored Procedure CREATE PROCEDURE dbo.VideoTapeLoadByCategoryIncrID @CategoryID int, @TotalRows int out AS BEGIN SELECT @TotalRows = (SELECT count(*) FROM VideoTape WHERE CategoryID=@CategoryID) SELECT TOP 10 VideoTapeID, CategoryID, Title, Description FROM

VideoTape WHERE CategoryID=@CategoryID Applied ADO.NET: Building Data-Driven Solutions END by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, stored namespaces, classes, TheVideoTapeLoadByCategoryIncrID procedure firstand gets the total number of records that are in the interfaces, and takes a comprehensive look at XML result set and stores it in an output variable. The second Select statement actually loads the first 10 rows from namespaces and classes, and how to integrate both with the database. ADO.NET.

To put this stored procedure to work, you need a custom indexer smart enough to transparently know when it needs return to the database to get the remaining records. Listing 19-13 shows the VideoCategoryIndexer. Table of to Contents Applied ADO.NET—Building Data-Driven Solutions

Listing 19-13: VideoCategoryIndexer


- ADO.NET Basics

Class VideoCategoryIndexer ChapterPublic 2 - Data Components in Visual Studio .NET Chapter 3


Chapter 4

As ArrayList -Private ADO.NET invids Connected Environments

Chapter 5

cnt AsEvents Integer -Private Handling ADO.NET

Chapter 6


Chapter 7


Public Sub New(ByVal catID As Integer, ByRef conn As SqlConnection) vids = New ArrayList() Chapter 8 - Constraints and Data Relations Dim sda As New SqlDataAdapter() Chapter 9 - ADO.NET Exception Handling sda.SelectCommand = New SqlCommand(_ Chapter 10 - Working with the ODBC .NET Data Provider "VideoTapeLoadByCategoryIncrID", conn) Chapter 11 - Stored Procedures and Views sda.SelectCommand.CommandType = _ Chapter 12 Oracle, SQLXML, and Other .NET Data Providers CommandType.StoredProcedure Chapter 13 - Developing a Custom Data Provider sda.SelectCommand.Parameters.Add(_ Chapter 14 - Developing Database Web Applications using ASP.NET "@CategoryID", SqlDbType.Int, 0, "CategoryID") Chapter 15 - Usingsda.SelectCommand.Parameters.Add(_ ADO.NET in Xml Web Services Chapter "@TotalRows", 16 - ASP.NETSqlDbType.Int) Server Controls and Data Binding sda.SelectCommand.Parameters("@TotalRows").Direction = _ Chapter 17 - Building Real-World Web Applications ParameterDirection.Output Chapter 18 - Object-Relational Mapping in .NET sda.SelectCommand.Parameters("@CategoryID").Value = catID Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Dim data As New VideoTapeData() Chapter 20 - COM Interoperability and ADO.NET sda.Fill(data) Chapter 21 - Messaging cnt = Convert.ToInt32(sda.SelectCommand.Parameters("@TotalRows").Value) Chapter 22 - SQL Server and ADO.NET: Notes on Performance vids.AddRange(VideoTapeDataAccess.GetVideoTapeArrayFromData(data)) Appendix A - Relational Databases: Some Basic Concepts End Sub Appendix B - Commonly Used SQL Statements


Public Function Count() As Integer Return cnt List of Figures End Function Index

List of Tables List of Listings Public Property Videos(ByVal index As Integer) As VideoTape List of Sidebars Get

If (index >= vids.Count) Then FullLoad() End If Return CType(vids(index), VideoTape) End Get Set(ByVal Value As VideoTape) vids(index) = Value End Set End Property Public ReadOnly Property LoadedCount() As Integer

Get Applied ADO.NET: Building Data-Driven Solutions Return vids.Count by Mahesh End Get Chand and David Talbot Apress © 2003 (928 pages) End Property

ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NETFullLoad() internals, namespaces, classes, and Private Function interfaces, and takes a comprehensive look at XML Dim dac As VideoTapeDataAccess() namespaces andNew classes, and how to integrate both with vids.Clear() ADO.NET.

vids.AddRange(dac.GetAllVideoTapes()) End Function Table of Contents End Class Applied ADO.NET—Building Data-Driven Solutions Introduction End Namespace Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3

- ADO.NET in Disconnected Environments VideoCategoryIndexer immediately loads the first 10 records in the constructor using an inline call to the Chapter 4 - ADO.NET in Connected Environments

VideoTapeLoadByCategoryIncrID stored procedure. The stored procedure also returns a count of the Chapter 5 - Handling ADO.NET Events number of-records that existed in the database in the @TotalRows output variable, which Integrating XML with ADO.NET VideoCategoryIndexer then stores in the member variable cnt.

Chapter 6 Chapter 7


Chapter 8 - Constraints Data Relations TheVideos() indexedand property accesses the internal ArrayList to get the requested VideoTape object. If the Chapter - ADO.NET Exception calling 9program requests one ofHandling the VideoTapes within the rage that's loaded, it returns it immediately. If the Chapter - Working with the Data Provider calling 10 program requests oneODBC of the.NET VideoTape objects that has not been loaded yet, it transparently loads the Chapter 11 Stored Procedures and Views entire collection. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

VideoCategoryIndexer would notProvider normally include a public LoadedCount property simply because the point Chapter 13 - Developing a Custom Data of an object such as this is to make incremental lazy loading transparent to the calling program. It's only Chapter 14 - Developing Database Webthe Applications using ASP.NET

included in this example to provide "proof" to the test case that it's indeed working. Listing 19-14 shows the test case for VideoCategoryIndexer.



Chapter - Building Real-World Web ApplicationsTest Case Listing17 19-14: The VideoCategoryIndexer Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding



Module IncLoadTestCase

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A -Main() Relational Databases: Some Basic Concepts Sub Appendix B - Commonly Used SQL Statements Appendix C -Console.WriteLine("Starting ADO.NET Frequently Asked Questions IncLoadTestCase") Index Dim iLoadCat As New VideoCategoryIndexer(3, _ List of Figures New SqlClient.SqlConnection(VideoCategoryDataAccess.connectionString)) List of TablesConsole.WriteLine("Loaded " + iLoadCat.LoadedCount.ToString() _

+ of " Listings out of " + iLoadCat.Count().ToString() + ".") List List of Sidebars

Console.WriteLine("Displaying First 10") Dim i As Integer For i = 0 To iLoadCat.LoadedCount - 1 Console.WriteLine("Item:" + iLoadCat.Videos(i).Title) Next Console.WriteLine("Displaying All") For i = 0 To iLoadCat.Count() - 1 Console.WriteLine("Item:" + iLoadCat.Videos(i).Title) Next

Console.WriteLine("Test Complete.") Applied ADO.NET: Building enter Data-Driven Console.WriteLine("Press key Solutions to quit.") ISBN:1590590732 by Mahesh Chand and David Talbot Console.ReadLine() Apress © 2003 (928 pages)

End Sub This text provides extensive coverage of ADO.NET technology End Module


Table Contents lazy loading test case first creates an instance of VideoCategoryIndexer. Second, it displays The of incremental Applied ADO.NET—Building Data-Driven Solutions the number of items loaded as well as the total count of items to be found in the database. Next, it displays all of Introduction theVideoTape objects currently loaded. Finally, it displays all of the items in the collection. As it does this final

step, it 1reaches out into the database and loads the remaining VideoTape objects as soon as the requested index Chapter - ADO.NET Basics is outside the loaded range.inFigure 19-9 shows Chapter 2 of - Data Components Visual Studio .NET the output of the incremental lazy loading test case that tests the LazyLoading component. Chapter 3 - ADO.NET in Disconnected Environments Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List ofFigure Tables 19-9: The incremental lazy loading test case output List of Listings List of amazing Sidebars thing about this test case is that the object's lazy loading functionality is completely transparent. That The

said, you can do certain things to enhance the functionality of this system. If you were to implement IEnumerable, this collection would be capable of being data bound to any of .NET's many controls. You would also be able to use it transparently as you would any other array. Another thing you can do to enhance the functionality of VideoCategoryIndexer is to integrate it into the VideoCategory object to use it as its internal means of loading the VideoTape objects that belong in the category. This, combined with implementing the IEnumerable interface, would allow you to use incremental lazy loading without modifying any code you may have written for the VideoCategory object. You'll want to consider your own problem carefully before using lazy loading. If parts of your application will always need the whole table, you need to keep VideoCategoryIndexer as a separate object only to be used when

you truly intend to do incremental lazy loading; otherwise you'll have code that calls two stored procedures instead Applied ADO.NET: Building Data-Driven Solutions of one. by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

Loading theThisDetail When the Master Is Loaded text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

The third main tool at your disposal working withlook potentially interfaces, and takeswhen a comprehensive at XML large master-detail relationships is loading the detail table whennamespaces the master table and classes, is loaded. andThe howadvantages to integrate of both doing withthis are minimizing the round trips required to the database toADO.NET. load and work with your objects. The situation where this strategy is beneficial is when you need to be able to display the master as well as most, or

Table ofthe Contents all, of detail. A good example is a page that displays 10 orders per page, and each order has 1 to 20 line items. Applied ADO.NET—Building Data-Driven Solutions The master table Order will always display the detail table Selection every time the master is displayed throughout Introduction the application. Chapter 1

- ADO.NET Basics

The solution is toComponents implement ainGetOrdersByDay() method (or whatever method of choosing the orders you Chapter 2 - Data Visual Studio .NET need to provide) that automatically calls the stored procedures to load the Orders and the Selections for that Chapter 3 - ADO.NET in Disconnected Environments day and then assemble them into your mapped objects in memory. Chapter 4 - ADO.NET in Connected Environments Chapter 5

- Handling ADO.NET Events Loading the detail automatically in situations where it's not needed increases the round trips to the database and

Chapter 6 -application Integratinglatency. XML with ADO.NET increases Always make sure that this is what your users will be doing most of the time when Chapter 7 Data Binding and Windows Forms Data-Bound Controls using this technique. Chapter 8

- Constraints and Data Relations In situations where you're loading more detail records than you'll be displaying, but you know that the user will be Chapter 9 - ADO.NET Exception Handling

asking 10 to see them fairly quickly, makes this technique Chapter - Working with the ODBC .NET Data Provider a good fit if you have a simple high-performance caching mechanism. Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Applied ADO.NET: Building Data-Driven Solutions Using a Near-Zero-Impact Caching Mechanism by Mahesh Chand and David Talbot

ISBN:1590590732

When working with mapped a number of places and situations call for a fast but not necessarily Apress © 2003objects, (928 pages) reliable caching mechanism. Although .NETcoverage is built toofbeADO.NET a highlytechnology scalable stateless model, it doesn't hurt This text provides extensive to use a little caching at the Web server as long as it doesn't consume including ADO.NET internals, namespaces, classes, and unnecessary resources. interfaces, and takes a comprehensive look at XML classes,isand how something to integrate such both as with A good example namespaces of where thisand is helpful loading an object for the currently logged-in ADO.NET. user. For each page view you get a cookie from the user that's their user ID, query the database, load it into the mapped object, and then display their first and last name in the header of the page. Using a simple caching mechanism eliminates many of these round trips and thus boosts scalability and reducing Table of Contents latency. Applied ADO.NET—Building Data-Driven Solutions

Introduction The problem with using a traditional cache that keeps items cached for a set amount of time is the amount Chapter 1 - consumed ADO.NET Basics of memory by the server increases for each user. The entire point of a stateless model is to Chapter 2 - Datawhere Components in usage Visual Studio .NETfor all of the incoming connections to the Web server. avoid situations memory increases Chapter 3 - ADO.NET in Disconnected Environments

In most4situations youincan use what Microsoft gives you by putting the Cache object to work. In situations Chapter - ADO.NET Connected Environments where you a layer of abstraction Chapter 5 -have Handling ADO.NET Events between what you're caching and ASP.NET, this simply isn't

possible without explicitly passing a reference to the Cache object to your data access components. Using - Integrating XML with ADO.NET good OR mapping practices such as abstracting your objects from the presentation layer make the Cache Chapter 7 - Data Binding and Windows Forms Data-Bound Controls object unusable in a mapped application. This unfortunately means that if you need a caching mechanism Chapter 8 - Constraints and Data Relations available in any situation where your code isn't executing on a Web server, you'll need to buy or write your Chapter 9 - ADO.NET Exception Handling own caching object. Because you can't use the Cache object in your data access components, the Chapter 10 - Working with the ODBC .NET Data Provider solution to implementing a caching system in the stateless model is to use weak references to your Chapter Stored Procedures objects.11A -weak reference is aand wayViews of referring to an object that tells the .NET runtime that if it needs the Chapter 12 Oracle, SQLXML, and .NET Data Providers memory for something else to goOther ahead and overwrite the space where your object is in memory. If you Chapter Developing Custom Data Provider attempt13to -access your aweak referenced object after its memory has been consumed by another process, Chapter 14 - Developing Database Applications using ASP.NET it will return the Visual Basic null Web constant Nothing. Listing 19-15 shows the WeakCache object, a cache Chapter 15 -consume Using ADO.NET in Xml Web Services that won't resources needed by other parts of the application. Chapter 6


Listing17 19-15: The WeakCache Object Chapter - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter Imports 19 -System Mapped Objects: Performance Considerations and Data Binding

Imports Chapter 20 -System.Collections COM Interoperability and ADO.NET Chapter 21 - Messaging

Namespace EnterpriseVB.VideoStore.Data Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Public Class Used WeakCache Appendix B - Commonly SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index

Private hash As Hashtable Private lastCleared As DateTime


Public Sub New() hash = New Hashtable() List of Sidebars lastCleared = DateTime.Now End Sub List of Listings

Public Property Items(ByVal key As String) As Object Get Dim ref As WeakReference If (hash(key) Is Nothing) Then Return Nothing End If If (lastCleared.Ticks + 1000000 < DateTime.Now.Ticks) Then Dim temp As Object lastCleared = DateTime.Now

temp = CType(hash(key), WeakReference).Target Applied ADO.NET: Building Data-Driven Solutions hash.Clear() ISBN:1590590732 by Mahesh lastCleared Chand and David = Talbot DateTime.Now Apress © 2003 (928 pages) Return temp

This text extensive coverage of ADO.NET technology Endprovides If including ADO.NET internals, namespaces, classes, and Return CType(hash(key), WeakReference).Target interfaces, and takes a comprehensive look at XML End Get and classes, and how to integrate both with namespaces Set(ByVal Value As Object) ADO.NET.

hash(key) = New WeakReference(Value) End Set Table of Contents End Property Applied ADO.NET—Building Data-Driven Solutions Introduction End Class Chapter 1

- ADO.NET Basics

Chapter End Namespace 2 - Data Components in Visual Studio .NET Chapter 3


Chapter 4


Chapter 5


TheWeakCache object creates an instance of a Hashtable and sets the lastCleared property to the - Integrating XML with ADO.NET current time. When the calling program sets a value in the Items indexed property, the WeakCache Chapter 7 - Data Binding and Windows Forms Data-Bound Controls object stores it as a WeakReference. Chapter 6 Chapter 8


Chapter 9 -calling ADO.NET Exception When the program triesHandling to get a value from the indexed property, a few things happen. As the Chapter 10is-accessed, Working with ODBC .NETobject Data Provider property thethe WeakCache checks to make sure the value being requested is not Chapter 11 -IfStored Procedures and Views Nothing. it's Nothing, it returns immediately to avoid a NullReferenceException. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Next, it 13 checks to see ifa1,000,000 ticks have passed since the lastAccessed time. If they have, the Chapter - Developing Custom Data Provider

WeakCache object clears the entire cache after updating the lastCleared time to the currentTime and returning the value for which the calling program has asked. You may be asking yourself the question, Chapter 15 - Using ADO.NET in Xml Web Services "If weak references don't hog memory, why ever clear the cache?" Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 16 - ASP.NET Server Controls and Data Binding

Chapter 17 -two Building Real-World There are primary reasons Web why Applications an occasional clearing of the cache is necessary. First, there has to be Chapter Object-Relational Mapping in .NET a check18to-make sure that cached objects have some kind of expiration date. It would be bad if a user Chapter - Mapped Performance Considerations and Data whose 19 account you Objects: locked out didn't expire until you rebooted theBinding server. The second reason is that Chapter although 20the - COM object Interoperability is weak referenced, and ADO.NET the key isn't. If you don't clear the Hashtable from time to time, Chapter these tiny 21 -little Messaging keys will pile up and consume a noticeable amount of memory toward a collision course

with the22greatest fear ofand all Web applications(Paging is when a machine runs out of available Chapter - SQL Server ADO.NET: Notes on paging. Performance RAM memory and hasDatabases: to start writing disk,Concepts which is substantially slower than RAM.) Appendix A - Relational SometoBasic Appendix B - Commonly Used SQL Statements

The final thing the getter method of the Items property indexer does is actually return the value. All of the checks prior to this step are necessary to guard against NullReferenceExceptions, keeping the data Index fresh and avoiding a memory leak. Appendix C - ADO.NET Frequently Asked Questions List of Figures

List of Tables Optimal areas to put a weak cache in your code are areas where large amounts of data, such as a detail List table, of Listings are loaded. Generally, in situations such as these, you want to cache the entire collection as a single

entry in the WeakCache object so if one of the objects in the detail collection gets overwritten, the whole List of Sidebars thing returns null. If you just cache the individual objects and scan through the collection to load the details, some records may have disappeared. You want an all-or-nothing situation.

Summary


ISBN:1590590732

In this chapter you learned how topages) use data binding with your mapped objects and how to overcome Apress © 2003 (928 common performance problems that arise when working with mapped objects. You can enhance the This text provides extensive coverage of ADO.NET technology performance of your application in a number of ways that are far easier including ADO.NET internals, namespaces, classes, and to implement if you put OR a comprehensive look at XML mapping to work interfaces, than if youand usetakes simple DataSet objects. namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 20: COM Interoperability and ADO.NET ISBN:1590590732 by Mahesh Chand and David Talbot

Overview


This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and The component object interfaces, Model and (COM) takes a has comprehensive been aroundlook for many at XMLyears and is used by many Windows namespaces and classes, to integrate both with applications. Eventually the .NET platformand willhow replace COM, but until then you may need to develop COM ADO.NET.

components from .NET and access them from unmanaged code, or you may want to use COM components in .NET applications. COM interoperability (also referred to as COM Interop) enables you to use existing COM components in .NET applications or use .NET components in unmanaged code. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Note In this chapter you'll see how to use ADO and other COM-based data access technologies through COM Interop in your .NET applications. However, COM interoperability is a wide area. If Chapter 1 you - ADO.NET want toBasics learn about COM interoperability in more detail, you may want to read COM and Chapter 2 .NET - DataInteroperability Components inby Visual Studio .NET (Apress, 2002). Andrew Troelsen Introduction

Chapter 3

- ADO.NET in Disconnected Environments The code for the .NET Framework is also referred to as managed code, and the code written for Chapter 4 written - ADO.NET in Connected Environments

traditional (previous to the .NET Framework) is called unmanaged code. Managed Chapter 5 -Windows Handling applications ADO.NET Events code contains metadataXML used byADO.NET the Common Language Runtime (CLR). Chapter 6 - Integrating with Chapter 7


In COM, type libraries stored metadata for a COM component and described the characteristics of a COM Chapter 8 - Constraints and Data Relations component. In .NET, an assembly is the primary building block of a .NET application. An assembly is a Chapter 9 of - ADO.NET Exception collection functionality that's Handling built, versioned, and deployed as a component. An assembly contains an Chapter 10 Working with the ODBC .NET Data Provider to a COM type library. The assembly manifest assembly manifest, which performs similar functions Chapter 11 Stored Procedures and Views includes information about an assembly such as the identity, version, culture, digital signature, compileChapter 12 - Oracle, SQLXML, Other Data Providers time dependencies, files thatand make up .NET the assembly implementation, and permissions required to run the Chapter 13 properly. - Developing a Custom Data Provider assembly Chapter 14 - Developing Database Web Applications using ASP.NET

In brief,15 COM understands language of type libraries, and the .NET Framework understands the Chapter - Using ADO.NET the in Xml Web Services

language of assembly manifests. So converting a type library into an assembly manifest provides accessibility to COM components from the managed code, and converting an assembly manifest to a Chapter 17 - Building Real-World Web Applications COM type library provides accessibility to .NET assemblies in unmanaged code. Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 18 - Object-Relational Mapping in .NET

Chapter - Mapped are Objects: and Data Binding Interop19 assemblies .NETPerformance assemblies Considerations that act as a bridge between managed and unmanaged code. Chapter - COM Interoperability and ADO.NET Interop20 assemblies provide mapping COM object members to equivalent .NET managed members. Chapter 21 - Messaging

The .NET a common set data types. All .NET programming languages use these Chapter 22 -Framework SQL Serverdefines and ADO.NET: Notes onofPerformance commonA data types. During the import process of a COM type library, there may be cases when the Appendix - Relational Databases: Some Basic Concepts

parameters and return values of COM objects use data types that do not correspond to .NET data types. The Interop marshaler handles these conversions for you. Interoperability marshaling is the process of Appendix C - ADO.NET Frequently Asked Questions packaging parameters and returning values into equivalent data types during conversion of a COM type Index library to an assembly manifest and an assembly manifest to a COM type library. Appendix B - Commonly Used SQL Statements

List of Figures

List ofTip Tables If you're looking for more COM-and Interop-related answers, you may want to look at the List of Listings System.Runtime.InteropServices namespace and its classes in the MSDN List of Sidebars documentation.

Applied ADO.NET: Building Data-Driven Solutions Exploring the .NET Interop Tools by Mahesh Chand and David Talbot

ISBN:1590590732

The .NET Framework many tools for runtime as well as Visual Studio .NET (VS .NET) users. Apressprovides © 2003 (928 pages) We'll use VS .NET for the applications in thiscoverage chapter,ofbut it doesn't hurt to take a look at these options. It's This text provides extensive ADO.NET technology easy to convert aincluding COM library into a .NET assembly using these tools. ADO.NET internals, namespaces, classes, and There are three different ways to do interfaces, and takes a comprehensive look at XML so. namespaces and classes, and how to integrate both with ADO.NET.

Using Visual Studio .NET

Table of Contents VS .NET provides a pretty simple way to import a type library in a managed application. The Project Ø Add Applied ADO.NET—Building Data-Driven Reference menu option allows you toSolutions access a COM library and add it to the project. This adds a Introduction namespace to the project, so you can access the library members through that namespace. Chapter 1

- ADO.NET Basics

- DataType Components in Visual Studio .NET and Exporter (Tlbimp.exe) Using the Library Importer

Chapter 2 Chapter 3

- ADO.NET in Disconnected Environments The Type Importer, known Environments as Tlbimp or Tlbimp.exe, is a command-line utility to convert a COM Chapter 4 Library - ADO.NET in Connected

type library a .NET assembly. Why a command-line utility? Well, this is an obvious question if you're Chapter 5 - into Handling ADO.NET Events using VS. can ignore this option if you use VS.NET for your development. This option is useful for Chapter 6 -You Integrating XML with ADO.NET developers have Chapter 7 - who Data don't Binding andVS.NET. Windows Forms Data-Bound Controls Chapter 8


Tlbimp.exe takes as a minimum one argument, the filename of the COM type library that you want to ADO.NET Exception Handling convert to -an equivalent .NET Runtime assembly. The output of Tlbimp.exe is a binary file that contains Chapter 10 - Working with the ODBC .NET Data Provider runtime metadata for the types defined in the original COM type library. Chapter 9


Chapter This is 12 the-syntax: Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 tlbFile - Developing Database Web Applications using ASP.NET tlbimp [options] Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

where tlbFile is the name of Web the COM type library. Chapter 17 - Building Real-World Applications Chapter 18 - Object-Relational Mapping in .NET

Table 20-1 describes some of the Tlbimp.exe options.

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Table 20-1: Tlbimp.exe Options Chapter 21 - Messaging

OPTION DESCRIPTION Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

/asmversion:versionNumber

Specifies the version of the assembly to produce


/helpC - ADO.NET Frequently Asked Questions Displays the available help commands Appendix Index /namespace List of Figures

Specifies the namespace in which to produce the assembly

List/out:filename of Tables

Specifies the name of output assembly

List/references:filename of Listings

Specifies the namespaces to use to resolve references to types defined outside the current type library

List of Sidebars

/?

Displays syntaxes and options for the tool

You can find Tlbimp.exe in the FrameworkSDK\Bin directory of your VS .NET or .NET Software Development Kit (SDK) installation.

Using the Type Library Exporter (Tlbexp.exe) The Type Library Exporter (Tlbexp.exe) does the reverse job of Tlbimp.exe. It generates an equivalent type library for a .NET assembly. This utility is useful when you need to use a managed code assembly in unmanaged code. Similar to Tlbimp, this utility also has options. The default command is as

follows:


tlbexp assemblyName

ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and where assemblyName is the name of the assembly for which you want to convert an equivalent type interfaces, and takes a comprehensive look at XML library. namespaces and classes, and how to integrate both with ADO.NET.

Table 20-2 describes some of the options. Table of 20-2: Contents Table Tlbexp.exe Options Applied ADO.NET—Building Data-Driven Solutions

OPTION

Introduction Chapter 1 /help Chapter 2

DESCRIPTION

- ADO.NET Basics Shows command syntax and options. - Data Components in Visual Studio .NET

/out:file Specifies the nameEnvironments of the type library to generate equivalent to an assembly. If - ADO.NET in Disconnected there are no options, the default name of the type library is the same as the Chapter 4 - ADO.NET in Connected Environments assembly. Chapter 3 Chapter 5


Chapter /? 6

- Integrating XML with ADO.NET Shows command syntax and options. - Data Binding and Windows Forms Data-Bound Controls

Chapter 7

You can Tlbexp.exe in theRelations FrameworkSDK\Bin directory of your VS .NET or .NET SDK Chapter 8 find - Constraints and Data installation. Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

Caution You can't use Tlbexp.exe to produce a type library from an assembly that was imported usingTlbimp.exe.




Applied ADO.NET: Building Data-Driven Solutions Using the ADO Recordset in ADO.NET by Mahesh Chand and David Talbot

ISBN:1590590732

In this example, you'll see how(928 to import Apress © 2003 pages) the ADO type library and use the ADO recordset to access a database. After that, you'll fill data to a DataSet fromofthe ADO recordset using a DataAdapter. This text provides extensive coverage ADO.NET technology including ADO.NET internals, namespaces, classes, and

Caution There's a cost and involved of performance when you use ADO in managed code because interfaces, takes in a terms comprehensive look at XML namespaces classes, how to integrate both with of COM Interop. and Using ADO and in managed code doesn't give you the same performance you can ADO.NET. get using and ADO.NET DataSet and DataReader. We use an ADO recordset only when we have no other option--for example, when you have a library that uses ADO and you need to use this library in managed applications. Table of Contents Applied Data-Driven Solutions To testADO.NET—Building this application, create a Windows application and drag a DataGrid control to the form from Toolbox. Introduction To add a reference to a COM type library, go to the Add Reference option from the Project menu and select Chapter 1 tab - ADO.NET Basics the COM in the Add Reference dialog box. As you can see from the Figure 20-1, we selected Microsoft Chapter - Data Components in Visual ActiveX2Data Objects 2.7 Library. ClickStudio Select.NET to add the selection to the Selected Components list. Now click Chapter OK. 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - 20-1: Messaging Figure Adding a reference to a COM library Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

This action adds the ADODB namespace to the project. You can see this namespace now listed in the project's namespaces (see Figure 20-2).




ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5

Handling ADO.NET Events Figure- 20-2: Namespace after adding ADODB namespace to the project

Chapter 6


Chapter 7 - Data Binding andreference Windows to Forms Data-Bound Controls After adding a namespace a project, its members are available for use in your project. You include this namespace in your application by calling Imports. You also should add a reference to the Chapter 8 - Constraints and Data Relations

System.Data.OleDb namespace because you'll use the OleDb DataAdapter to fill a DataSet. So, add Chapter 9 - ADO.NET Exception Handling these two to theData project with this: Chapter 10 -name-space Working withreferences the ODBC .NET Provider Chapter 11 - Stored Procedures and Views Chapter Imports 12 -ADODB Oracle, SQLXML, and Other .NET Data Providers

Imports Chapter 13 -System.Data.OleDb Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Now you can use the ADO recordset and connection to access a database. As you can see from Listing 20-1, you create a Connection object and set the connection mode and cursor location. After that, you call the Chapter 17 - Building Real-World Web Applications connection's Executemethod to execute a SQL statement that returns the _Recordset object. The Fill Chapter 18 - Object-Relational Mapping in .NET method of the DataAdapter reads data from a recordset and fills data to a DataSet. As you can see from Chapter 19 -you Mapped Performance Considerations and Data this code, createObjects: a DataSet and DataAdapter and call theBinding DataAdapter'sFill method. The Fill Chapter 20 COM Interoperability and ADO.NET method takes three parameters: a DataSet, a recordset, and a DataSet name. Finally, you bind the Chapter 21 -toMessaging DataSet a DataGrid to fill data from the DataSet to the DataGrid. Chapter 16 - ASP.NET Server Controls and Data Binding


Listing 20-1: Using an ADODB Some Namespace to Access a Database Appendix A - Relational Databases: Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C -Sub ADO.NET Frequently Asked Questions Private Form1_Load(ByVal sender As System.Object, _ Index ByVal e As System.EventArgs) Handles MyBase.Load List Figures SQL and Connection strings ' of Create List Dim of Tables ConnectionString As String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _

"Data Source=c:\\Northwind.mdb" List of Listings Dim sql As String = "SELECT CustomerId, CompanyName, ContactName From Customers" List of Sidebars ' Create a Connection object and open it Dim conn As Connection = New Connection() Dim connMode As Integer = CType(ConnectModeEnum.adModeUnknown, Integer) conn.CursorLocation = CursorLocationEnum.adUseServer conn.Open(ConnectionString, "", "", connMode) Dim recAffected As Object = Nothing Dim cmdType As Integer = CType(CommandTypeEnum.adCmdText, Integer) Dim rs As _Recordset = conn.Execute(sql, recAffected, cmdType) ' Create dataset and data adapter objects Dim ds As DataSet = New DataSet("Recordset") Dim da As OleDbDataAdapter = New OleDbDataAdapter()

' Call data adapter's Fill method to fill data from ADO Applied ' Recordset to the ADO.NET: dataset Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot da.Fill(ds, rs, "Customers") Apress © 2003 (928 pages) ' Now use dataset This text provides extensive coverage of ADO.NET technology DataGrid1.DataSource = ds.DefaultViewManager including ADO.NET internals, namespaces, classes, and End Sub interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

The output of Listing 20-1 looks like Figure 20-3. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure 20-3: Displaying data from an ADO recordset to a DataGrid



Once you access ADO in managed Chapter 20 -know COM to Interoperability and ADO.NETcode, you can do anything you want including adding, updating, and deleting data using an ADO recordset. Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Applied Building Data-Driven Solutions Using ADOX withADO.NET: ADO.NET by Mahesh Chand and David Talbot

ISBN:1590590732

Microsoft ActiveXApress Data Objects Extensions for Data Definition Language and Security (ADOX) is an © 2003 (928 pages) extension to ADOThis thattext provides an object model to manipulate data definition and security. provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

You can use ADOX in managed codeaincomprehensive a similar way look that you used an ADO recordset in the previous interfaces, and takes at XML classes, andlibrary how to integrate both with section. Just add namespaces a reference and to ADOX type using VS .NET's Add Reference option and use the ADO.NET. namespace and its members as you would in unmanaged code. To test this, create a new Windows application. After that, add a reference to the Microsoft ADO Ext. 2.7 for DLL and Security component to the project (see Figure 20-4).

Table of Contents


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure 20-4: Adding a reference to ADOX library


Chapter 18 - Object-Relational Mapping .NET After adding the reference, you'll see in that the ADOX namespace is listed in the available namespaces in Chapter your application 19 - Mapped (seeObjects: Figure Performance 20-5). Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 20-5: ADOX namespace listed in project references Now, the only thing you need to do is to use the namespace and its members. The ADOX classes should

be available in your application after adding Imports ADOX to the project. ADOX provides objects that Applied ADO.NET: Building Data-Driven you can use to create databases, tables, and columns. TheSolutions Catalog object represents a database and by Mahesh Chand and David Talbot itsCreate method creates a new database. The Table objectISBN:1590590732 represents a database table. You can add Apress © 2003 (928 pages) columns to a Table object using the Columns collection's Append method. Listing 20-2 creates a new text provides extensive coverage ADO.NET technology Microsoft AccessThis database called Test.mdb with theoftable MyTable and two columns, col1 and col2, in it. including ADO.NET internals, namespaces, classes, and

interfaces, and takes a comprehensive look at XML Listing 20-2: Using ADOX from Managed Code


Private Sub Form1_Load(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles MyBase.Load Table of Contents ' Create SQL and Connection strings Applied ADO.NET—Building Data-Driven Solutions Dim ConnectionString As String = _ Introduction "Provider=Microsoft.Jet.OLEDB.4.0; Data Source=c:\\Test.mdb" ChapterTry 1 - ADO.NET Basics Chapter 2 ' -Create Data Components in Visual Studio .NET a Catalog object Chapter 3 Dim - ADO.NET Disconnected Environments ct As inCatalog = New Catalog() Chapter 4 ct.Create(ConnectionString) - ADO.NET in Connected Environments Chapter 5 ' -Create Handling ADO.NET a tableEvents and two columns Chapter 6 Dim - Integrating dt As Table XML with = ADO.NET New Table() = "MyTable" Chapter 7 dt.Name - Data Binding and Windows Forms Data-Bound Controls DataTypeEnum.adInteger, 4) Chapter 8 dt.Columns.Append("col1", - Constraints and Data Relations dt.Columns.Append("col2", DataTypeEnum.adVarWChar, 255) Chapter 9 - ADO.NET Exception Handling ' Add table to the tables Chapter 10 - Working with the ODBC .NET Datacollection Provider ct.Tables.Append(CType(dt, Object)) Chapter 11 - Stored Procedures and Views Catch exp As Exception Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers MessageBox.Show(exp.Message.ToString()) Chapter 13 - Developing a Custom Data Provider End Try Chapter 14 - Developing Database Web Applications using ASP.NET End Sub Chapter 15 - Using ADO.NET in Xml Web Services


Solutions Accessing Applied OLAPADO.NET: ServerBuilding Data Data-Driven with ADO.NET by Mahesh Chand and David Talbot

ISBN:1590590732

On-Line Analytical Processing (OLAP) Apress © 2003 (928 pages) is a service that represents raw data in a variety of views of information that'sThis easily understandable by the users. of OLAP provides consistent and fast access to the data, text provides extensive coverage ADO.NET technology which can be represented in personalized views in the real world without considering the size and complexity including ADO.NET internals, namespaces, classes, and interfaces, andOLAP takes can a comprehensive look XML of the database. For example, represent data in at the form of three-dimensional cubes and cells. namespaces and classes, and how integrate both The server involved in this processing is called an to OLAP server. Thewith OLAP server is a high-capacity, ADO.NET. multiuser data manipulation engine specifically designed to work on multidimensional data structures. The ActiveX Data Objects Multi-Dimensional Library (ADOMD) provides access to OLAP server data. OLAP services extract, summarize, organize, and store data warehouses in multidimensional structures, also Table of Contents known as OLAP server cubes. Applied ADO.NET—Building Data-Driven Solutions Introduction

To test this OLAP sample, you'll use the FoodMart 2000 database that comes with Microsoft SQL Server - ADO.NET Basics Analysis Server. Before testing this sample, you must have SQL Server 2000 Analysis Server running. If you Chapter 2 - Data Components in Visual Studio .NET don't have SQL Server 2000 Analysis Server running, you can install it from Microsoft SQL Server CD by Chapter 3 SQL - ADO.NET Disconnected Environments selecting Serverin2000 Components Ø Install Analysis Services. This option installs SQL Server 2000 Chapter 4 ADO.NET in Connected Environments Analysis Server on your machine. Chapter 1

Chapter 5

- Handling ADO.NET Events Note Analysis Services may not install the FoodMart 2000 database. You may need to restore Chapter 6 Installing - Integrating XML with ADO.NET

database the C:\Program Files\Microsoft Analysis Services\Samples\ Chapter 7 the - Data Bindingfrom and Windows Forms Data-Bound Controls file. You can restore a database by using Analysis Manager Ø Meta Data Ø Chapter 8 foodmart - Constraints2000.cab and Data Relations option. Chapter 9 Restore - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

ADOMD functionality is defined in the msadomd.dll library. If this library is not listed in your COM components list, you can use the Browse button on the Add Reference dialog box to browse for it. The Chapter - Oracle, Other .NET Data Providers default 12 path for thisSQLXML, library isand C:\Program Files\Common Files\System\ADO (see Figure 20-6). Chapter 11 - Stored Procedures and Views

Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List ofFigure Tables 20-6: Browsing the msadomd.dll library List of Listings List of Sidebars

After adding a reference to the msadomd.dll, the Add Reference dialog box looks like Figure 20-7.


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Figure 20-7: Adding a reference to msadomd.dll library

Chapter 6

- Integrating XML with ADO.NET Now click OKBinding button and to add the reference. This actionControls adds the ADOMD namespace to the project (see Chapter 7 the - Data Windows Forms Data-Bound

Figure 820-8). Chapter - Constraints and Data Relations Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List ofFigure Tables 20-8: ADOMD namespace listed in the project namespaces List of Listings

Now you can use the Imports directive to include the ADOMD namespace in your project and use ADOMD classes.

List of Sidebars

To test the source code, create a Windows application and add two ListBox controls, two Button controls, aTextBox control, and a Label controls and set their properties (see Figure 20-9).


ISBN:1590590732



- ADO.NET Basics

Figure Windows form to testStudio ADOMD Chapter 2 - 20-9: Data Components in Visual .NET Chapter 3


Chapter 4 -references ADO.NET in Environments Next, add of Connected ADOMD and ADODB in the application as follows: Chapter 5 - Handling ADO.NET Events Chapter 6 -ADODB Integrating XML with ADO.NET Imports Chapter 7 -ADOMD Data Binding and Windows Forms Data-Bound Controls Imports Chapter 8


Chapter 9

- ADO.NET Exception Handling Also, add following in .NET the beginning of the form class: Chapter 10 the - Working withvariables the ODBC Data Provider Chapter 11 - Stored Procedures and Views

Private As String Chapter 12 -strConn Oracle, SQLXML, and Other .NET Data Providers Private Asa Custom Connection Chapter 13 -dbConn Developing Data Provider Private As Catalog Chapter 14 -dtCatalog Developing Database Web Applications using ASP.NET Private As CubeDefs Chapter 15 -cubes Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

After that, create Connection and Catalog objects on the form load and use CubeDefs of Catalog to

Chapter 18 -cubes. Object-Relational in Listing .NET 20-3, you then add all cubes to the ListBox and the number get all the As you canMapping see from Chapter 19to- the Mapped Objects: Performance Considerations and Data Binding of cubes TextBox. Chapter 20 - COM Interoperability and ADO.NET Chapter Listing21 20-3: - Messaging Getting All Available Cubes from the FoodMart 2000 Database Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A -Sub Relational Databases: Some Basic Concepts Private Form1_Load(ByVal sender As System.Object, _ Appendix B -eCommonly Used SQL StatementsHandles MyBase.Load ByVal As System.EventArgs) Appendix - ADO.NET Frequently Askedstring Questions ' C Construct connection Index strConn = "Provider=msolap; Data Source = MCB;" & _ List of Figures "Initial Catalog = FoodMart 2000; User ID =sa; Pwd="

' Create and open a connection List of Tables dbConn = New Connection() List of Listings dbConn.Open(strConn, "", "", _ List of Sidebars CType(ConnectModeEnum.adModeUnknown, Integer)) ' Create a Catalog object and set it's active connection ' as connection dtCatalog = New Catalog() dtCatalog.ActiveConnection = CType(dbConn, Object) ' Get all cubes cubes = dtCatalog.CubeDefs ' Set text box text as total number of cubes TextBox1.Text = cubes.Count.ToString() Dim cube As CubeDef For Each cube In cubes Dim str As String = ""

ListBox1.Items.Add(cube.Name.ToString()) AppliedName ADO.NET: Data-Driven Solutions str = "Cube :" +Building cube.Name.ToString() + ", " ISBN:1590590732 by Mahesh Chand and David Talbot str += "Description :" + cube.Description.ToString() + ", " © 2003 (928 pages) str += Apress "Dimensions :" + cube.Dimensions.Count.ToString() This text provides extensive coverage of ADO.NET technology Next including ADO.NET internals, ListBox1.SetSelected(0, True)namespaces, classes, and interfaces, and takes a comprehensive look at XML End Sub namespaces and classes, and how to integrate both with ADO.NET.

Table Contents If youofrun the application, the output looks like Figure 20-10. Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure All available in the FoodMart 2000 database Chapter 13 - 20-10: Developing a Customcubes Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

The Get Dimensions button gets the dimensions of the selected cube in the left box in Figure 20-10.Listing 20-4 returns the dimensions of a cube and adds it to the right box of Figure 20-10.


Chapter 16 - ASP.NET Server Controls and Data Binding Chapter - Building Real-World Web Applications Listing17 20-4: Getting All Dimensions of a Cube Chapter 18 - Object-Relational Mapping in .NET


Private Sub Button1_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles Button1.Click Chapter 21 - Messaging ' Get the selected cube Chapter 22 - SQL Server and ADO.NET: Notes on Performance Dim cube As CubeDef = cubes(ListBox1.SelectedItem.ToString()) Appendix - Relational Databases: Some Basic Concepts ' AGet all the dimensions of the selecte cube Appendix B -iCommonly Used SQL Statements Dim As Integer Appendix C -iADO.NET Asked Questions For = 0 ToFrequently cube.Dimensions.Count - 1 Step i + 1 Index Dim dimen As Dimension = cube.Dimensions(i) List of Figures ListBox2.Items.Add(dimen.Name.ToString()) List of Tables Next ListBox2.SetSelected(0, True) List of Listings End Sub List of Sidebars Chapter 20 - COM Interoperability and ADO.NET

The output of the Get Dimensions button fills the right box with the dimensions (see Figure 20-11).


ISBN:1590590732


Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1 - 20-11: ADO.NET Basicsdimensions of a cube Figure Getting Chapter 2 - Data Components in Visual Studio .NET

The Get button Environments returns the properties of a dimension such as name, hierarchies, Chapter 3 Dimension - ADO.NETMembers in Disconnected UniqueName, and Properties (seeEnvironments Listing 20-5). Chapter 4 - ADO.NET in Connected Chapter 5


Chapter 6


Chapter 7


Listing 20-5: Getting Dimension Members

Private Button2_Click(ByVal sender As System.Object, _ Chapter 8 -Sub Constraints and Data Relations ByVal e As System.EventArgs) Handles Button2.Click Chapter 9 - ADO.NET Exception Handling ' Get the selected cube Chapter 10 - Working with the ODBC .NET Data Provider Dim cube As CubeDef = cubes(ListBox1.SelectedItem.ToString()) Chapter 11 - Stored Procedures and Views ' Get the selected Dimension Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Dim dimen As Dimension = cube.Dimensions(ListBox2.SelectedItem.ToString()) Chapter 13 - Developing a Custom Data Provider

ChapterMessageBox.Show("Dimension 14 - Developing Database Web Applications using ASP.NET Properties :: Name=" + dimen.Name.ToString() & _ Chapter 15 ", - Using ADO.NET in Xml Web Services Description=" + dimen.Description.ToString() + ", Hierarchies=" & _ Chapter 16 dimen.UniqueName.ToString()) - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications End Sub Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

The output Listing 20-5 looks like Figure 20-12. Chapter 21 - of Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List ofFigure Figures20-12: Viewing dimension properties List of Tables List of Listings List of Sidebars

Summary


ISBN:1590590732

Even though the Apress .NET Framework uses a new approach to access data sources (through ADO.NET), it © 2003 (928 pages) provides COM interoperability services to access previous data access libraries. In this chapter, you This text provides extensive coverage of ADO.NET technology learned how to use ADO, ADOX, ADOMD, and OLAP services in managed applications using the COM including ADO.NET internals, namespaces, classes, and Interop services. interfaces, and takes a comprehensive look at XML

namespaces and classes, and how to integrate both with ADO.NET. Messaging service is one more popular topic these days. In the next chapter, you'll get a brief overview of

messaging services and learn how you can access them in the .NET Framework. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 21: Messaging ISBN:1590590732 by Mahesh Chand and David Talbot

Overview


This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Messaging services interfaces, are oneand of the takes most a comprehensive effective and popular look at XML mediums to communicate between two namespaces classes, and how to integrate both with machines. It doesn't matter if and you're a high-tech developer, a stockbroker, a high-school student, or a ADO.NET.

businessperson. In some way, you use messaging services. Some of the common messaging services are electronic mail (email), instant messenger services, text messaging via phones, or messaging used in complex distributed applications. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

We could easily write a book on messaging itself. In this chapter, we'll give you a brief overview of messaging services and how you can access them in the .NET Framework.


- ADO.NET Basics

Chapter The messaging 2 - Data functionality Componentsin inthe Visual .NET Studio Framework .NET Library is accessible through the

System.Messaging chapter starts by introducing you to the basics of messaging and Chapter 3 - ADO.NET innamespace. DisconnectedThis Environments theSystem.Messaging namespace. After that, we'll show you how to use messaging classes to write Chapter 4 - ADO.NET in Connected Environments real-world messaging applications. Chapter 5 -distributed Handling ADO.NET Events Chapter 6


So, what is messaging? A message is some data transferred between two machines. These machines can - Data Binding and Windows Forms Data-Bound Controls be two computers or other devices such as cell phones. These machines may be attached to each other Chapter 8 - Constraints and Data Relations via the Internet, a local area network, or a wireless network. A message can be a simple text message, a Chapter 9 - ADO.NET Exception Handling string, some streaming data, some live streaming data, or some complex objects. Messaging is the Chapter 10 Working with the ODBC .NET Data from Provider process of sending and receiving messages one machine to another. Chapter 7


Amessage a mediator two machines. When a sender sends a message, it goes to a Chapter 12 - queue Oracle,isSQLXML, and between Other .NET Data Providers queue that the message makes sure the receiver gets the message. A message queue also Chapter 13 - holds Developing a Customand Data Provider guarantees the deliveryDatabase of the message. One of the simplest examples of this is email exchange using Chapter 14 - Developing Web Applications using ASP.NET Microsoft If you have anyWeb message in your Outbox, Outlook will try to send it until it leaves. The Chapter 15 Outlook. - Using ADO.NET in Xml Services messaging service that handles message queues in Microsoft Windows is called Microsoft Message Queuing (MSMQ).



ADO.NET: Building Data-Driven Solutions IntroducingApplied Types of Queues by Mahesh Chand and David Talbot

ISBN:1590590732

You can divide queues two categories: user and system. The user queues are used by a group of Apressin © 2003 (928 pages) network users, and system queues are used by the system. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Using User Queues

You can further categorize the user queues into four categories: public, private, administration, and response queues. Table of Contents

The public queues are published on the network's shared areas, which are available to all the valid users Applied ADO.NET—Building Data-Driven Solutions of the network. In other words, all of the authorized users of the network can access these queues. Introduction Chapter 1

- ADO.NET Basics

Unlike public queues, the private queues are not published on the network. Instead, they are published Chapter 2 - Data Components in Visual Studio .NET and available only on the local machine that contains them. Only the workgroup users can access this Chapter - ADO.NET in Disconnected Environments type of 3queue. To access private queues, a user has to pass the path and label of the queue. A path of the Chapter 4 ADO.NET in Connected Environments queue is a folder where queues are stored. Chapter 5

- Handling ADO.NET Events The administration queues messages acknowledging the receipt of messages, and the response Chapter 6 - Integrating XML contain with ADO.NET

queues7contain received byForms the destination applications. Chapter - Datamessages Binding and Windows Data-Bound Controls Chapter 8


- ADO.NET Exception Handling Using System Queues

Chapter 9


You can divideProcedures the systemand queues Chapter 11also - Stored Views into four categories: journal, dead letter, report, and private system queues. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

The journal queues can store copies of messages that applications send by using a queue. They also store the messages removed from a queue. Each client machine maintains a journal queue for outgoing Chapter 15 - and Using ADO.NET in Xml Web Services messages, the server also maintains a journal queue for each individual queue. Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 16 - ASP.NET Server Controls and Data Binding

The dead queues stores undelivered and expired messages. This queue is maintained on the client Chapter 17 -letter Building Real-World Web Applications machine Chapter 18only. - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

The report queues contain messages that store the route of a message. These queues are also stored on the client machine, and the private system queues store administrative and notification messages.



Applied ADO.NET: Building Data-Driven Solutions Installing Message Queuing by Mahesh Chand and David Talbot

ISBN:1590590732

Before you start working you must ensure that you've installed MSMQ on the server. You can Apress ©with 2003 MSMQ, (928 pages) install MSMQ by This selecting Control Panel Ø Add/Remove Programs Ø Message Queuing Services. If you text provides extensive coverage of ADO.NET technology aren't running Windows 2000 or later versions, the installation may ask including ADO.NET internals, namespaces, classes, and you to insert your Windows CD. interfaces, and takes a comprehensive look at XML Windows 2000 (Professional and Server) installs MSMQ with the operating system by default. namespaces and classes, and how to integrate both with ADO.NET. To see if you have MSMQ installed your machine, you can select Control Panel Ø Administrative Tools Ø

Computer Management and then expand the Message Queuing node, as shown in Figure 21-1. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure 21-1: Viewing the Messaging Queuing node from Computer Management



Caution If you don't see the Message Queuing option here, you must install it.



Applied ADO.NET: Building Data-Driven Solutions Using the System.Messaging Namespace by Mahesh Chand and David Talbot

ISBN:1590590732

Before writing messaging applications, Apress © 2003 (928 pages) let's take a quick look at the key classes provided by the System.Messaging namespace. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

TheMessageQueue class isand thetakes mostaimportant class look in theatSystem.Messaging namespace. This interfaces, comprehensive XML namespaces and classes, and how to integrate both with class represents a messaging queue in a messaging queuing server. This class provides members to ADO.NET. send messages to and receive messages from MSMQ. The Create and Delete static methods of this class create and delete message queues, respectively. This class also provides methods to retrieve and filter private and public queues available on the server. Table of Contents Applied ADO.NET—Building Data-Driven Solutions TheMessage class is another important class of the System.Messaging namespace. The Message Introduction object represents a message in message queuing. This class provides access to messages of a message Chapter - ADO.NET Basics that you can use to read a message body, label, priority, posting time, queue.1It provides properties Chapter - Data Components Visual Studio .NET sender,2authentication mode, in and so on. Chapter 3

- ADO.NET in Disconnected Environments TheMessageEnumerator class represents an enumeration, which provides a forward-only cursor Chapter 4 - ADO.NET in Connected Environments

through5 messages a message queue, which you can use to navigate through from the first message to Chapter - HandlinginADO.NET Events

the last in -a Integrating message queue. An enumerator returns information about the message at the current cursor XML with ADO.NET position. It doesn't remove the message from the queue.

Chapter 6 Chapter 7


Chapter 8 - Constraints and Data Relations TheMessagePropertyFilter class controls and filters messages from a message queue. The Chapter 9 - ADO.NET Exception Handling MessageReadPropertyFilter property of MessageQueue uses the MessagePropertyFilter Chapter object. 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

TheMessageQueueEnumerator class provides a forward-only cursor that you can use to enumerate Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers (loop) through the messages in aData server. Chapter 13 - Developing a Custom Provider Chapter 14 - Developing Database Webclass Applications usingaASP.NET TheMessageQueueTransaction represents transaction in message queuing. A complete Chapter 15 Using ADO.NET in Xml Web Services messaging transaction contains a successful send and successful receive. The Chapter 16 - ASP.NET Server Controls Data or Binding MessageQueueTransaction canand commit roll back transactions. Messages sent to transactional Chapter 17 Building Real-World Web Applications queues are removed if a transaction is rolled back, and messages received from transactional queues are Chapter 18to- the Object-Relational Mapping in is .NET returned queue if the transaction rolled back. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

TheTrustee class represents aand user or a group account with a set of access rights that is trying to Chapter 20 - COM Interoperability ADO.NET

access a messaging item. The AccessControlEntry class allows, denies, or revokes access rights to a trustee. Chapter 22 - SQL Server and ADO.NET: Notes on Performance Chapter 21 - Messaging

Appendix A - Relational Databases: Basic Concepts TheAccessControlList classSome represents a loss of access control entries that specify access rights for Appendix - Commonly Used SQL Statements trustees.BIt's a collection of AccessControlEntry objects. Appendix C - ADO.NET Frequently Asked Questions

TheSystem.Messaging namespace also provides some formatting-related classes. These classes are Index ActiveXMessengerFormatter, BinaryMessageFormatter, and XmlMessageFormatter. List of Figures List of Tables

Messaging in .NET is compatible with previous versions of MSMQ. ActiveXMessengerFormatter provides interoperability functionality, so you can use MSMQ ActiveX controls in the .NET Framework.

List of Listings

List of Sidebars

TheBinaryMessageFormatter class serializes and deserializes objects to or from the body of a message in a binary format. XML is the default format used by MSMQ and messaging services. XmlMessageFormatter is responsible for serializing and deserializing objects to or from the body of a message in Extensible Markup Language (XML) format using XML Schema Definition (XSD). Finally, the System.Messaging namespace also provides one messaging-related exception handling class:MessageQueueException. This class represents the exception that is thrown if an MSMQ internal error occurs.

Applied ADO.NET: Queues Building Data-Driven Solutions Working with Message by Mahesh Chand and David Talbot

ISBN:1590590732

TheMessageQueue class is a(928 wrapper Apress © 2003 pages) around MessageQueuing, which defines functionality to access and manage a queue on an MSMQ server. This classofalso provides methods to create and delete queues, This text provides extensive coverage ADO.NET technology send and receiveincluding messages, and retrieve queues and messages. ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Using the MessageQueue Properties

It's always a good idea to know what functionality is provided by a class before using the class. Table 21-1 Table of Contents describes the MessageQueue class properties. Applied ADO.NET—Building Data-Driven Solutions Introduction Table 21-1: The MessageQueue Class Properties Chapter 1

- ADO.NET Basics

Chapter 2


PROPERTY

DESCRIPTION

Chapter 3 - ADO.NET in Disconnected Environments Authenticate This property represents whether a queue will accept only Chapter 4 - ADO.NET in Connected Environments authenticated messages. The queue will reject

nonauthenticated messages. Both get and set.

Chapter 5


Chapter 6


Chapter 7


BasePriority

Chapter 8

This property represents the base priority of messages. Both get and set.

- Constraints and Data Relations CanRead Chapter 9 - ADO.NET Exception Handling This property is true if a message queue can be read;

it's false. Both get and set. Chapter 10 - Working with the ODBC .NET otherwise, Data Provider Chapter 11 - Stored Procedures and Views This property is true if a message queue can be written to; CanWrite Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers otherwise, it's false. Both get and set. Chapter 13 - Developing a Custom Data Provider

Category This property Chapter 14 - Developing Database Web Applications usingrepresents ASP.NET the queue category. Both get and set.

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and This Dataproperty Binding gets the time and date the queue was CreateTime Chapter 17 - Building Real-World Web Applications created. Chapter 18 - Object-Relational Mapping in .NET

DefaultPropertyToSend

This represents the default message property when an application sends a message. Both get and set.


DenySharedRecieve Chapter 21 - Messaging

This property is true if the queue has exclusive access to

receive messages from the MSMQ queue; otherwise, it's Chapter 22 - SQL Server and ADO.NET: Notes on Performance false. Both get and set. Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements EnableConnectionCache When this property is true, a cache of connections will be Appendix C - ADO.NET Frequently Asked Questions maintained by the application; otherwise, they won't. Both Index List of Figures

EncryptionRequired

List of Tables

List of Listings ListFormatName of Sidebars

get and set. If this property is true, the queue accepts only nonprivate (nonencrypted) messages. Both get and set. This property represents the unique queue name generated by MSMQ when queue was created. Read only.

Formatter

This property represents the formatter used to serialize and deserialize. Both get and set.

Id

This property represents the unique queuing identifier. Read only.

Label

This property represents the queue description. Both get and set.

LastModifyTime

This property represents the last time the properties on a queue were modified. Read only.

MachineName Applied ADO.NET: Building This property represents the name of the computer where Data-Driven Solutions queue is located. Both read and write. ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) This property represents the maximum size of the journal MaximumJournalSize This text provides extensive coverage of ADO.NET queue. Both get and set. technology including ADO.NET internals, namespaces, classes, and

interfaces, and takes a comprehensive look at XMLthe maximum size of the queue. MaximumQueueSize This property represents namespaces and classes, andget howand to integrate both with Both set. ADO.NET.

MessageReadPropertyFilter Table of Contents

This is the property filter for receiving or peeking messages. Both get and set.

PathADO.NET—Building Data-Driven Solutions This property represents the queue path. Both get and set. Applied Introduction

QueueName

Chapter 1

- ADO.NET Basics

Chapter 2

This property represents the queue's user-friendly name. Both get and set.

- Data Components in Visual Studio .NET ReadHandle This property represents the native handle used to read Chapter 3 - ADO.NET in Disconnected Environments Chapter 4

messages from the queue. Read only. - ADO.NET in Connected Environments

Chapter 5 - Handling ADO.NET Events SynchronizingObject Chapter 6

This property represents the object that marshals the event

Chapter 7

- Integrating XML with ADO.NET handler calls resulting from a ReceiveCompletedor - Data Binding and Windows Forms Data-Bound Controls PeekCompleted event. Both get and set.

Chapter 8


Chapter 9


Transactional

When this property is true, the queue accepts only transactions.


UseJournalQueue Chapter 11 - Stored Procedures and Views If this property is true, received messages are copied to the journal queue. Both get and set. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

WriteHandle

This property represents the native handle used to send messages to the queue. Read only.



Managing Queues Using VS .NET



In Visual Studio .NET (VS .NET), the Server Explorer provides options to manage messaging queues in

Chapter 20 - COMserver. Interoperability and all ADO.NET the messaging You can see available queues by expanding the Chapter 21 Messaging Servers\MachineName\Message Queues node. The Message Queues node has three children-Private Chapter 22Public - SQL Queues, Server and ADO.NET: on Performance Queues, and System Notes Queues-that list private, public, and system queues, respectively. Appendix - Relational Databases:available Some Basic Concepts You canAsee the corresponding queues by expanding these nodes (see Figure 21-2). Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure 21-2: Managing message queues through the Server Explorer


The Server Explorer also allows you to create and delete queues. To create a queue, right-click the

Chapter - Mapped Objects: Performance Considerations and Data Binding Private19 Queues or Public Queues node and select the Create Queue option. Chapter 20 - COM Interoperability and ADO.NET

Note may not be able to view or create public queues if you're a member of a proper domain or Chapter 21 You - Messaging on a and WORKGROUP computer. Chapter 22 working - SQL Server ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Now if you expand an available queue, you'll see children: Journal Messages and Queue Messages. You can also delete messages from a queue by simply right-clicking and selecting the Clear Messages menu Appendix C - ADO.NET Frequently Asked Questions option. Appendix B - Commonly Used SQL Statements Index

List ofTip Figures After creating a message queue using the Server Explorer, you can easily add it to your List of Tables application by simply dragging the queue from the Server Explorer to a form. This action adds an

object of type MessageQueue to your project. List of Listings List of Sidebars

Retrieving Available Queues TheMessageQueue class provides six methods, which you can use to retrieve private and public queues. TheGetPrivateQueuesByMachine method retrieves private queues available on the server (see Listing 21-1). Listing 21-1: Retrieving Private Queues Dim queList As MessageQueue() = _ MessageQueue.GetPrivateQueuesByMachine(".")

Dim que As MessageQueue ADO.NET: Building Data-Driven Solutions For Each que Applied In queList ISBN:1590590732 by Mahesh Chand and David Talbot Console.WriteLine(que.Path) Apress © 2003 (928 pages) Next que This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with TheGetPublicQueues ADO.NET.method returns public queues on the server (see Listing 21-2).

Listing 21-2: Retrieving Public Queues Table of Contents Applied ADO.NET—Building Data-Driven Solutions Sub GetPublicQueuesMethod() Introduction Try Chapter 1 Dim - ADO.NET Basics queList As MessageQueue() = _ ChapterMessageQueue.GetPublicQueues() 2 - Data Components in Visual Studio .NET Chapter 3 Dim - ADO.NET Disconnected Environments que Asin MessageQueue Chapter 4 For - ADO.NET Each que in Connected In queList Environments Chapter 5

-Console.WriteLine(que.Path) Handling ADO.NET Events

que Chapter 6 Next - Integrating XML with ADO.NET exp As Exception ChapterCatch 7 - Data Binding and Windows Forms Data-Bound Controls Chapter 8 Console.WriteLine(exp.Message) - Constraints and Data Relations

End Try Chapter 9 - ADO.NET Exception Handling End Sub

Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider TheGetPublicQueuesByCategory method returns public queues that belong to the specified Chapter 14 This - Developing using category. method Database takes the Web ID ofApplications the queue as an ASP.NET argument, which can be retrieved by using the Id Chapter 15 Using ADO.NET in Xml Web Services property of MessageQueue. Chapter 16 - ASP.NET Server Controls and Data Binding

TheGetPublicQueuesByMachine method returns public queues that belong to the specified machine. Chapter 17 - Building Real-World Web Applications This method takes the machine nameinas an argument. Chapter 18 - Object-Relational Mapping .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

TheGetPublicQueuesByLabel method returns public queues that have the specified label.


Chapter 21 All - Messaging Note GetPublicXXX and GetPrivateQueuesByMachine methods are static methods. Hence, Chapter 22 they - SQLcan't Server and ADO.NET: Notes on Performance class instances. be used through the MesssageQueue Appendix A - Relational Databases: Some Basic Concepts

Listing 21-3 retrieves public queues based on the specified category, machine, and label. Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Listing 21-3: Filtering Queues Based on Category, Machine Name, and Label

Index

List of Figures

Sub GetQueuesByCategoryMethod() List of Tables Try List of Listings Dim queList As MessageQueue() = _ MessageQueue.GetPublicQueuesByCategory(New _ Guid("{00000000-0000-0000-0000-000000000001}")) Dim que As MessageQueue For Each que In queList Console.WriteLine(que.Path) Next que Catch exp As Exception Console.WriteLine(exp.Message) End Try End Sub

List of Sidebars

Public Sub GetQueuesByLabelMethod()

Try AppliedAs ADO.NET: Building Data-Driven Solutions Dim queList MessageQueue() = _ ISBN:1590590732 by Mahesh Chand and David Talbot MessageQueue.GetPublicQueuesByLabel("LabelName") Apress © 2003 (928 pages) Dim que As MessageQueue Thisque text provides extensive coverage of ADO.NET technology For Each In queList including ADO.NET internals, namespaces, classes, and Console.WriteLine(que.Path) interfaces, and takes a comprehensive look at XML Next que namespaces and classes, and how to integrate both with Catch expADO.NET. As Exception Console.WriteLine(exp.Message) End Try TableEnd of Contents Sub Applied ADO.NET—Building Data-Driven Solutions Introduction Public Sub GetQueuesByMachineMethod() ChapterTry 1 - ADO.NET Basics Chapter 2 Dim - Data queList Components As MessageQueue() in Visual Studio .NET = _ ChapterMessageQueue.GetPublicQueuesByMachine("MCB") 3 - ADO.NET in Disconnected Environments

que Asin MessageQueue Chapter 4 Dim - ADO.NET Connected Environments Each que In Events queList Chapter 5 For - Handling ADO.NET Chapter 6

-Console.WriteLine(que.Path) Integrating XML with ADO.NET

que Chapter 7 Next - Data Binding and Windows Forms Data-Bound Controls Catch exp As Exception - Constraints and Data Relations Console.WriteLine(exp.Message) Chapter 9 - ADO.NET Exception Handling End Try Chapter 10 - Working with the ODBC .NET Data Provider End Sub Chapter 8


Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Filtering Queues Using MessageQueueCriteria



You can even filter public queues by using GetPublicQueues. This method takes an argument of type MessageQueueCriteria. The MessageQueueCriteria class provides properties you can use to Chapter 18 - Object-Relational Mapping in .NET filter queue types (see Table 21-2). Chapter 17 - Building Real-World Web Applications

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Class Properties Table 21-2: The MessageQueueCriteria Chapter 21 - Messaging

PROPERTY DESCRIPTION Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Category

Filters queues based on this category (both get and set)


CreatedAfter Filters queues created after this time (both get and set) Appendix C - ADO.NET Frequently Asked Questions Index CreatedBefore List of Figures

Filters queues created before this time (both get and set)

ListLabel of Tables

Filters queues based on this label (both get and set)

ListMachineName of Listings

Filters queues based on this machine name (both get and set)

List of Sidebars

ModifiedAfter

Filters queues based on the queues modified after this time (both get and set)

ModifiedBefore

Filters queues based on the queues modified before this time (both get and set)

UsingMessageQueueCriteria, you can simply filter the queues. The following code filters queues based on a machine name and label: Dim filter As New MessageQueueCriteria() Filter.MachineName = "MCB"

filter.Label = "LabelName " Applied ADO.NET: Building Dim queList As MessageQueue() = _ Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot MessageQueue.GetPublicQueues(filter) Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, comprehensive look at XML class, call the RemoveAll method. Tip To remove all filtersand settakes by thea MessageQueueCriteria namespaces and classes, and how to integrate both with ADO.NET.

Creating and Deleting Message Queues Programmatically Table of Contents TheCreate method of MessageQueue creates a queue on the server. This method has two overloaded Applied Data-Driven Solutions of the path of the queue, and the second form takes a path forms.ADO.NET—Building The first form takes only one argument Introduction with a Boolean argument, which represents whether the queue will be created as a transactional queue. Chapter 1 - ADO.NET Basicsforms of the Create method: The following shows both Chapter 2


Chapter 3 - ADO.NET Disconnected Environments Overloads Publicin Shared Function Create(String) As MessageQueue Chapter 4 ADO.NET in Connected Environments Overloads Public Shared Function Create(String, Boolean) As MessageQueue Chapter 5


Chapter 6

- Integrating XML with ADO.NET TheCreate method returns an objectForms of type MessageQueue. Chapter 7 - Data Binding and Windows Data-Bound ControlsYou can create a public queue or a

private 8queue using theand Create method. The type of queue created depends on the path of the queue. Chapter - Constraints Data Relations For a public queue, the path syntax is MachineName\QueueName; for a private queue, the path syntax is Chapter 9 - ADO.NET Exception Handling MachineName\Private$\QueueName. Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

The following code creates one public and one private queue:


MessageQueue.Create(".\MyPubQ") MessageQueue.Create(@".\Private$\MyPrivatQ")


Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET TheDelete method of MessageQueue deletes a queue on the server. Similar to the Create method, Chapter 19 - Mapped Objects: Performance andpath DataofBinding the deletion of the public or private queueConsiderations depends on the the queue. The following code deletes a Chapter public and 20 -aCOM private Interoperability queue from and the ADO.NET server: Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance MessageQueue.Delete(".\MyPubQ") Appendix A - Relational Databases: Some Basic Concepts MessageQueue. Delete (@".\Private$\MyPrivatQ") Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

TheExists method checks whether a queue path is available.

Index

List of Figures

Note TheCreate,Delete, and Exists methods are static methods and hence can't be used through the MessageQueue class instances.

List of Tables

List of Listings

List of Sidebars

ADO.NET: Building Data-Driven Solutions Creating a Applied Sample Application by Mahesh Chand and David Talbot

ISBN:1590590732

Now let's create aApress sample application. © 2003 (928 pages)Create a Windows application and add controls to the form so that the final form looks like Figure 21-3. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - 21-3: Working with theQueue ODBC .NET Data form Provider Figure Message Manager Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

The Create Queue button reads the name from New Queue Name text box and creates a new queue on the server. Listing 21-4 shows a Create Queue button event handler, which reads the queue name from a Chapter 14 - Developing Database Web Applications using ASP.NET text box and creates a private queue. It also sets the priority of the queue based on the user's option Chapter 15on - Using ADO.NET in Xml Web Services selected the form. The Transactional check box is responsible for creating a transactional queue. Chapter 13 - Developing a Custom Data Provider

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter Listing17 21-4: - Building Creating Real-World a Queue Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 -Sub Mapped Objects: Performance Considerations and DataAs Binding Private CreateQueueBtn_Click(ByVal sender System.Object, _ Chapter 20 -eCOM and ADO.NET ByVal As Interoperability System.EventArgs) Handles CreateQueueBtn.Click ChapterDim 21 -str Messaging As String = String.Empty ChapterDim 22 -trn SQL Server and ADO.NET: Notes on Performance As Boolean = False Appendix ' AIf- Relational transactional Databases:type Some is Basic true Concepts

IfB CheckBox1.Checked Then Appendix - Commonly Used SQL Statements trn = TrueFrequently Asked Questions Appendix C - ADO.NET Index End If

' If queue is private List of Figures If RadioButton1.Checked Then List of Tables str = ".\Private$\" End If List of Sidebars str += TextBox1.Text If Not MessageQueue.Exists(str) Then currentQueue = MessageQueue.Create(str, trn) If currentQueue Is Nothing Then ' Set priority If RadioButton4.Checked Then currentQueue.BasePriority = _ Convert.ToInt16(MessagePriority.High) ElseIf RadioButton5.Checked Then currentQueue.BasePriority = _ Convert.ToInt16(MessagePriority.Low) Else List of Listings

currentQueue.BasePriority = 0 Applied ADO.NET: Building Data-Driven Solutions End If ISBN:1590590732 by Mahesh Chand and David Talbot ListBox1.Items.Add(TextBox1.Text) Apress © 2003 (928 pages) ListBox1.Update() End If This text provides extensive coverage of ADO.NET technology End If including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML End Sub namespaces and classes, and how to integrate both with ADO.NET.

Table Contents The of Delete Queue button deletes the queue from the server (see Listing 21-5). Applied ADO.NET—Building Data-Driven Solutions

Listing 21-5: Deleting a Queue Introduction Chapter 1

- ADO.NET Basics

Chapter 2 -Sub Data DeleteQueBtn_Click(ByVal Components in Visual Studio .NET sender As System.Object, _ Private Chapter 3 -eADO.NET in Disconnected Environments ByVal As System.EventArgs) Handles DeleteQueBtn.Click ChapterDim 4 -str ADO.NET As String in Connected = String.Empty Environments

queue is private Chapter'5 If- Handling ADO.NET Events Then ChapterIf 6 RadioButton1.Checked - Integrating XML with ADO.NET = ".\Private$\" Chapter 7 str - Data Binding and Windows Forms Data-Bound Controls ChapterEnd 8 -If Constraints and Data Relations

TextBox2.Text Chapterstr 9 -+= ADO.NET Exception Handling ' Create and connect to a public Message Queuing queue. If MessageQueue.Exists(str) Then Chapter 11 - Stored Procedures and Views MessageQueue.Delete(str) Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers End If Chapter 13 - Developing a Custom Data Provider End Sub Chapter 10 - Working with the ODBC .NET Data Provider


Chapter 17 - Building Real-World Web Applications The Queue Properties button simply returns the current queue properties (see Listing 21-6). Chapter 18 - Object-Relational Mapping in .NET

Listing19 21-6: Getting a Queue's Properties Chapter - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 -Sub Messaging Private QuePropsBtn_Click(ByVal sender As System.Object, _ Chapter ByVal 22 -eSQL AsServer System.EventArgs) and ADO.NET: NotesHandles on Performance QuePropsBtn.Click

Dim AsDatabases: String Some = "Format Name: " + currentQueue.FormatName Appendix A -props Relational Basic Concepts props += ", Base Priority:" Appendix B - Commonly Used SQL Statements + currentQueue.BasePriority.ToString() props += ", Frequently Create Time:" + currentQueue.CreateTime.ToString() Appendix C - ADO.NET Asked Questions Index props += ", ID:" + currentQueue.Id.ToString()

props += ", Path:" + currentQueue.Path.ToString() List of Figures props += ", Max Size:" + currentQueue.MaximumQueueSize.ToString() props += ", Transaction:" + currentQueue.Transactional.ToString() List of Listings MessageBox.Show(props) List of Sidebars End Sub List of Tables

Creating a MessageQueue Instance The simplest way to create a MessageQueue instance is just drag a queue from the Server Explorer to a form in the form designer. This action adds a MessageQueuecomponent to the form. But most of the time you'll be creating a MessageQueue instance programmatically. For that, you create a MessageQueue object and set its path. For example, the following code creates a MessageQueue instance programmatically:


Dim mq = new MessageQueue() by Mahesh Chand and David Talbot mq.Path = ".\mcbQueue"

ISBN:1590590732


This text provides extensive coverage of ADO.NET technology namespaces, classes,constructor and Alternatively, youincluding can alsoADO.NET pass the internals, path in the MessageQueue as follows: interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Dim mq = new ADO.NET. MessageQueue(".\mcbQueue")

Table of Contents

Setting a Queue's Path


You can create a MessageQueue instance from a path, from a format name, or from a label. Each of - ADO.NET Basics these methods has their advantages. For example, in XML Web services, the format name method gives Chapter 2 - Data Components in Visual Studio .NET you better performance than the path method. When a queue is disconnected, the path method won't Chapter 3 - ADO.NET in Disconnected Environments work. You have to use the format method. Chapter 1

Chapter 4


Chapter 5 of - Handling ADO.NET Events The path queue takes the form servername\queuename. Each type of queue has a unique path. Chapter 6 the - Integrating with ADO.NET Actually, path is theXML combination of machine name and queue name of a queue. You can use the

MachineName QueueName properties MessageQueue Chapter 7 - Dataand Binding and Windows Forms of Data-Bound Controlsand combine them to get the path of a queue.8 Chapter


Chapter 9


Table 21-3 describes the paths for different types of queues.


Table 21-3: Path for Different Types of Queues

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter QUEUE 13 TYPE - Developing a Custom Data Provider

PATH


Public queue

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16queue - ASP.NET Server Controls and Data Binding Private Chapter 17 - Building Real-World Web Applications

Journal queue


MachineName\QueueName MachineName\Private$\QueueName MachineName\QueueName\Journal$

MachineName\Journal$ Chapter Machine 19 -journal Mapped queue Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Machine dead-letter queue


MachineName\Deadletter$

Machine dead-letter queue Chapter 22 -transactional SQL Server and ADO.NET: Notes on PerformanceMachineName\XactDeadletter$ Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Tip The dot (.) represents the current machine in a path. For example, MessageQueue1.Path=".\mcbQueue" represents the mcbQueue queue on the current Index machine. Appendix C - ADO.NET Frequently Asked Questions List of Figures

List of following Tables The code uses the path of the queue: List of Listings List of Sidebars MessageQueue1.Path=".\mcbQueue"

You can use format names to indicate whether a queue is public or private. The FORMATNAME:PUBLIC=QueueGUID,FORMATNAME:PRIVATE=MachineGUID\QueueNumber, and FORMATNAME:PUBLIC=QueueGUID;JOURNAL names represent public, private, and journal queues, respectively. The following code sets the path of the queue as a public queue using format names: MessageQueue1.Path = "FORMATNAME:PUBLIC=queueGUID"

You can also use a label name to refer to a queue. The Label property of MessageQueue represents Applied ADO.NET: Building Data-Driven Solutions the label of a queue: by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

MessageQueue1.Path="LABEL:mcbQueue"


Sending and Receiving Messages

TheSend method of MessageQueue is responsible for sending a message to the queue. Using these forms, you can even specify the type of MSMQ transaction. The Send message takes the first argument of Table of Contents type Object, which can be a Message object, a text string, or any other message. The Send method Applied ADO.NET—Building Data-Driven Solutions has six overloaded forms: Introduction Chapter 1

- ADO.NET Basics

Overloads Public Sub Send(Object) Chapter 2 - Data Components in Visual Studio .NET Overloads Public Sub Send(Object, _ Chapter 3 - ADO.NET in Disconnected Environments MessageQueueTransaction) Chapter 4 - ADO.NET in Connected Environments Overloads Public Sub Send(Object, _ Chapter 5 - Handling ADO.NET Events MessageQueueTransactionType) Chapter 6 - Integrating XML with ADO.NET Overloads Public Sub Send(Object, String) Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Overloads Public Sub Send(Object, String, _ Chapter 8 - Constraints and Data Relations MessageQueueTransaction) Chapter 9 - ADO.NET Exception Handling Overloads Public Sub Send(Object, String, _ Chapter 10 - Working with the ODBC .NET Data Provider MessageQueueTransactionType) Chapter 11 - Stored Procedures and Views


TheReceive method receives first message using in theASP.NET queue and removes it from the queue. If there's Chapter 14 - Developing Databasethe Web Applications no message available in theinqueue, you can even specify a time span, and the method will wait for that Chapter 15 - Using ADO.NET Xml Web Services interval16 or -until the next message is available in the queue. The Receive method has six overloaded Chapter ASP.NET Server Controls and Data Binding forms: 17 - Building Real-World Web Applications Chapter Chapter 18 - Object-Relational Mapping in .NET

Public Function Receive() As Message Chapter 19 Overloads - Mapped Objects: Performance Considerations and Data Binding Overloads Public Function Chapter 20 - COM Interoperability and Receive ADO.NET _ (MessageQueueTransaction) As Message Chapter 21 - Messaging Overloads Public Function _ Chapter 22 - SQL Server and ADO.NET:Receive Notes on Performance (MessageQueueTransactionType) As Concepts Message Appendix A - Relational Databases: Some Basic Overloads Public Function Receive(TimeSpan) As Message Overloads Public Function Receive(TimeSpan, _ Appendix C - ADO.NET Frequently Asked Questions MessageQueueTransaction) As Message Index Overloads List of Figures Public Function Receive(TimeSpan, _ List of Tables MessageQueueTransactionType) As Message Appendix B - Commonly Used SQL Statements


Both the Send and Receive methods take an argument of type MessageQueueTransactionType enumeration, which specify the type of transaction. It can be Automatic,None, or Single. The None type transaction represents that the operation will not be transactional. The Single option is for single internal transactions, and the Automatic type is used for Microsoft Transaction Server (MTS) or COM+ 1.0 services.

Walking Through Simple Messaging Application Before discussing messaging any further, let's create a simple messaging application using VS .NET. In this application, you'll send and receive messages using a Windows application.

First, add two Label controls, two TextBox controls, two Button controls, and a DataGrid control to Applied Building Data-Driven Solutions the form. Second, set the ADO.NET: second TextBox control's Multiline property to true. The final application by Mahesh Chand and David Talbot looks like Figure 21-4. As you can see, you'll read the title andISBN:1590590732 body of a message. The Send Message Apress © 2003 (928 pages) and the Receive Messages button will read all the messages from button will send message to the queue, This text provides coverage the queue and display them in the extensive DataGrid control.of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Figure 21-4: A simple messaging application


After creating a Windows application, open Chapter 18 - Object-Relational Mapping in .NETthe Server Explorer and expand the Message Queues node. Right-click Private Queues node and Considerations click the Createand Queues menu item. Type mcbQ in the text box Chapter 19 -the Mapped Objects: Performance Data Binding and then OK. Don't select the check box. To verify the action, you should now have a Chapter 20 click - COM Interoperability andTransactional ADO.NET mcbQ queue listed under your Private Queues node. Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Now drag the mcbQ queue to the form. This action adds a reference to the System.Messaging

Appendix A - Relational Some Concepts namespace and addsDatabases: an object of typeBasic MessageQueue called MessageQueue1. Appendix B - Commonly Used SQL Statements

Appendix Finally, the C - only ADO.NET thingFrequently you need to Asked do isQuestions add code to send and receive messages. Listing 21-7 shows the

code of the Send Message button click event handler. As you can see, the code simply reads the title and Index body text, creates a Message object, sets its Label and Body properties, and then calls the List of Figures MessageQueue.Send method. List of Tables List of Listings

Listing 21-7: Sending Messages to a Queue

List of Sidebars

Private Sub SendMsgBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles SendMsgBtn.Click Dim msg As System.Messaging.Message = _ New System.Messaging.Message(titleTextBox.Text) msg.Label = titleTextBox.Text msg.Body = bodyTextBox.Text MessageQueue1.Send(msg) End Sub

Applied Data-Driven Note We'll discuss theADO.NET: MessageBuilding class in more detail inSolutions the following sections. by Mahesh Chand and David Talbot

ISBN:1590590732

Listing 21-8 readsApress messages a queue and adds them to the DataGridcontrol. As you can see, this © 2003 from (928 pages) code calls the GetAllMessages method MessageQueue, which returns an array of Message This text provides extensiveofcoverage of ADO.NET technology objects. After thatincluding it simplyADO.NET reads theinternals, Label and Body properties of a namespaces, classes, and Message and adds them to a and is takes a comprehensive look control at XML to display the results. DataTable. Thisinterfaces, DataTable bound to the DataGrid namespaces and classes, and how to integrate both with ADO.NET.Messages from a Queue Listing 21-8: Receiving Table of Contents Private Sub RecMsgBtn_Click(ByVal sender As System.Object, _ Applied ByVal ADO.NET—Building e As System.EventArgs) Data-Driven Solutions Handles RecMsgBtn.Click

' Create a DataTable in memory Introduction As New DataTable() ChapterDim 1 -dtTable ADO.NET Basics ChapterdtTable.Columns.Add("Title") 2 - Data Components in Visual Studio .NET

Body") ChapterdtTable.Columns.Add("Message 3 - ADO.NET in Disconnected Environments As System.Messaging.Message ChapterDim 4 -messages() ADO.NET in Connected Environments messages = MessageQueue1.GetAllMessages() - Handling ADO.NET Events ' Need a formatter to get the text of the message body. Chapter 6 - Integrating XML with ADO.NET Dim stringFormatter As System.Messaging.XmlMessageFormatter = _ Chapter 7 - Data Binding and Windows Forms Data-Bound Controls New System.Messaging.XmlMessageFormatter(New String() _ Chapter 8 - Constraints and Data Relations {"System.String"}) Chapter 9 - ADO.NET Exception Handling Dim index As Integer ChapterDim 10 -msg Working the ODBC .NET Data Provider As with System.Messaging.Message Chapter 5

Chapter 11 - Stored Procedures and Views ChapterFor 12 -index Oracle, SQLXML, Other .NET Data Providers = 0 To and messages.Length - 1 Chapter 13 - Developing a Custom Data Provider messages(index).Formatter = stringFormatter Chapter 14 - Developing Database Web Applications using ASP.NET msg = messages(index) Chapter 15 Dim - Using rowADO.NET As DataRow in Xml Web = dtTable.NewRow() Services

row(0) = Server msg.Label Chapter 16 - ASP.NET Controls and Data Binding row(1) = Real-World msg.Body.ToString() Chapter 17 - Building Web Applications dtTable.Rows.Add(row) Chapter 18 - Object-Relational Mapping in .NET ChapterNext 19 - Mapped Objects: Performance Considerations and Data Binding

= ADO.NET dtTable ChapterDataGrid1.DataSource 20 - COM Interoperability and End Sub

Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Now, run the application, enter the title and body of the messages, and click Send Message to send

Appendix C -to ADO.NET Frequently Asked Questions messages the queue. When you're done sending messages, click the Receive Messages button to read Index all the messages from the queue (see Figure 21-5). List of Figures List of Tables List of Listings List of Sidebars


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6

- Integrating XML with ADO.NET Figure Messaging application in action Chapter 7 - 21-5: Data Binding and Windows Forms Data-Bound Controls Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions Working with Messages by Mahesh Chand and David Talbot

ISBN:1590590732

TheMessage class represents a message in MSMQ. The Message class provides one static method Apress © 2003 (928 pages) calledInfiniteTimeout that specifies that no timeout exists. This class provides more than 40 This text provides extensive coverage of ADO.NET technology properties and some of them represent the body text, format, security, including ADO.NET internals, namespaces, classes, and ID, and priority of the message. interfaces, and takes comprehensive look at XML You'll see this class's properties in theasample applications throughout this chapter. namespaces and classes, and how to integrate both with ADO.NET.

Creating and Removing Messages

Table Contents You of can use the Message class to create a message. Once you have created a message, you can use it Applied as an argument ADO.NET—Building of the Send Data-Driven and Receive Solutions methods of MessageQueue to send and receive messages. Introduction The following code creates a message and sets its priority, body, and label: Chapter 1

- ADO.NET Basics

Chapter 2 - Data Components Visual Studio .NET Dim msg1 As Message = inNew Message() Chapter 3 - ADO.NET Disconnected Environments msg1.Priority = inMessagePriority.High Chapter msg1.Body 4 - ADO.NET = "Body in Connected of first Environments message"

msg1.Label = "First Message" Chapter 5 - Handling ADO.NET Events Chapter 6


Chapter 7


Chapter 9


ThePurge method of MessageQueue removes all the messages from a queue. The following code Chapter 8 - Constraints and Data Relations removes messages from MessageQueue1: Chapter 10 - Working with the ODBC .NET Data Provider

MessageQueue1.Purge()

Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13remove - Developing a Custom Data Provider You can a single message from the queue by calling the Receivemethod of MessageQueue. Chapter 14also - Developing Database Web Applications using ASP.NET You can use the ReceiveById method to remove a message identified by the ID. You can also call Chapter 15 - Using ADO.NET in Xml Web Services thePeekById method to find a specific message and then use the RecieveById method to remove it. Chapter 16 - ASP.NET Server Controls and Data Binding

Tip17 You can always remove messages manually from the Server Explorer by selecting the Queue Chapter - Building Real-World Web Applications Messages Ø Clear Messages menu Chapter 18 - Object-Relational Mapping in .NET option. There's no way you can remove a single message from a queue manually. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Setting Queue and Message Priorities



You can set both a queue's and a message's priority. Both MessageQueue and Message classes provide properties to set their priorities. You can use the BasePriority property of MesssageQueue to get and Appendix B - Commonly Used SQL Statements set a priority of a queue. It's only applied on public queues. The BasePriority of a private queue is Appendix C - ADO.NET Frequently Asked Questions always 0. Appendix A - Relational Databases: Some Basic Concepts

Index

List of can Figures You use the Priority property of the Message class to get and set the priority of a message. The List of Tables MessagePriority enumeration specifies the value of the Priority property. Table 21-4 describes the List MessagePriority of Listings enumeration members. List of Sidebars

Table 21-4: The MessagePriority Enumeration Members

PROPERTY


Lowest

by Mahesh Chand and David Talbot Lowest priority Apress © 2003 (928 pages)

VeryLow Low Normal AboveNormal Table of Contents High

ISBN:1590590732

Low and Lowest message priority technology ThisBetween text provides extensive coverage of ADO.NET including ADO.NET internals, namespaces, classes, and Low priority interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Normal priority ADO.NET. BetweenHigh and Normal message priority High priority


VeryHigh Introduction

BetweenHighest and High message priority

Chapter 1 - ADO.NETHighest Basics priority Highest Chapter 2 - Data Components in Visual Studio .NET Chapter 3 - ADO.NET in Disconnected Environments The following code creates two messages and sets their priority, body, and label properties: Chapter 4 - ADO.NET in Connected Environments Chapter 5

ADO.NET Events Dim msg1- Handling As Message = New Message()

Chapter 6 - Integrating XML with ADO.NET Dim msg2 As Message = New Message() Chapter 7 - Data Binding and Windows Forms Data-Bound Controls msg1.Priority = MessagePriority.High Chapter 8 - Constraints Relations msg1.Body = "Bodyand ofData first message" Chapter 9 - ADO.NET Exception Handling msg1.Label = "First Message" Chapter 10 - Working=with the ODBC .NET Data Provider msg2.Priority MessagePriority.Normal Chapter msg2.Label 11 - Stored = "Second ProceduresMessage" and Views

msg2.Body = "Body of and second message" Chapter 12 - Oracle, SQLXML, Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

AppliedTransactional ADO.NET: Building Data-Driven Solutions Understanding Messaging by Mahesh Chand and David Talbot

ISBN:1590590732

Transactional messaging is the process Apress © 2003 (928 pages) of sending and receiving messages in transactions. A transaction is a set of one or This moretext messages. Transactional messages are grouped inside a transaction context, provides extensive coverage of ADO.NET technology which keeps trackincluding of the transaction states. ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces andtwo classes, andthat how integrate both with in a transaction either are delivered Transaction processing ensures things: alltomessages bundled ADO.NET. together in order or that none of the messages participating in a transaction are sent if there's a failure in transaction. The success of a transaction is called a committed transaction, and the failure of a transaction is called an aborted transaction. Table of Contents Applied ADO.NET—Building Data-Driven Solutions In message queuing, there are two types of transactions: internal and external. In the internal transaction Introduction process, the message transfer happens between two queues belonging to a queuing server. On the other Chapter 1 external - ADO.NET Basics involves message transfer between a queue and other resources (not hand, an transaction Chapter - Data Components Visual Studio related2to queuing) such as a in database. This.NET chapter discusses internal transactions only. Chapter 3


Chapter 4

- ADO.NET in Connected Environments Using the MessageQueueTransaction Class

Chapter 5


Chapter 6 - Integrating XML with ADO.NET TheMessageQueueTransaction class represents an internal transaction. This class has a property Chapter calledStatus, 7 - Datawhich Binding represents and Windows the status Formsof Data-Bound the transaction. Controls The status of a transaction is of type

MessageQueueTrasactionStatus enumeration type. It has four values: Aborted,Committed, Chapter 8 - Constraints and Data Relations Initialized, and Pending. Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

TheAborted value represents the transaction has been aborted, and there will be no changes in the current state of the messages. The Committed value indicates that the transaction has been committed Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers and all message were sent as expected. The Initialized value indicates that the transaction has been Chapter 13 - Developing a Custom Data Provider initialized but not started yet. The Pending value represents that the transaction has been started and is Chapter 14 - Developing Database Web Applications using ASP.NET still in process. Chapter 11 - Stored Procedures and Views


Besides16the StatusServer property, the MessageQueueTransaction has three methods: Abort,Begin, Chapter - ASP.NET Controls and Data Binding andCommit. The Abort method rolls back the pending transaction. The Begin method starts a Chapter 17 - Building Real-World Web Applications transaction, and the CommitMapping method in saves Chapter 18 - Object-Relational .NETthe pending transactions. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

To create an internal transaction, you can use the Create method of MessageQueueTransaction, and when you're sure you want to commit or roll back the transaction, you call Commit or Abort Chapter 21 - Messaging methods. Chapter 20 - COM Interoperability and ADO.NET


Creating Transactional Queues



Do you remember when you created a new message queue in the Server Explorer using the Create Queue menu option? When you create a queue using the Server Explorer, there's a check box on the List of Figures dialog box that allows you to create a transactional queue (see Figure 21-6). Index


Figure 21-6: Creating a transactional queue using the Server Explorer Creating a transactional message queue programmatically is pretty simple. When you use the Create method of MessageQueue, you pass the second argument as true to create a transactional message

queue. For example, the following code creates a transactional queue: Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

Dim mq as New MessageQueue Apress © 2003 (928 pages) mq =MessageQueue.Create(".\mcbTransQueue", True)


Sending and Receiving Transactional Messages

When creating a transactional queue, the Send and Receive methods of MessageQueue take the last argument as the transaction object. Listing 21-9 shows how to send and receive transactional messages. Table of Contents As you can see from this Data-Driven code, the transaction Applied ADO.NET—Building Solutions is only committed where there were no errors; otherwise, the transaction is aborted. Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Listing 21-9: Sending and Receiving Transactional Messages

Imports Chapter 4 -System ADO.NET in Connected Environments Imports -System.Messaging Handling ADO.NET Events

Chapter 5 Chapter 6


Chapter 7


Chapter 8


Module Module1

Sub Main() - ADO.NET Exception Handling 'SendTransactionalMessages() ChapterRecieveTransactionalMessages() 10 - Working with the ODBC .NET Data Provider Chapter - Stored Procedures and Views End11Sub Chapter 9

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Public Sub SendTransactionalMessages() ChapterDim 14 -mq Developing Database Web Applications using ASP.NET As MessageQueue = New MessageQueue() Chaptermq 15 =- Using MessageQueue.Create(".\Private$\mcbTQ", ADO.NET in Xml Web Services True)

AsServer MessageQueueTransaction = _ ChapterDim 16 -tran ASP.NET Controls and Data Binding ChapterNew 17 -MessageQueueTransaction() Building Real-World Web Applications ChapterTry 18 - Object-Relational Mapping in .NET

tran.Begin() Chapter 19 - Mapped Objects: Performance Considerations and Data Binding mq.Send("Body of first message", "Message1", tran) Chapter 20 - COM Interoperability and ADO.NET mq.Send("Body of second message", "Message2", tran) mq.Send("Body of third message", "Message3", tran) Chapter 22 - SQL Server and ADO.NET: Notes on Performance tran.Commit() Appendix A - Relational Databases: Some Basic Concepts Console.WriteLine("Transaction committed!") Appendix B - Commonly Used SQL Statements Catch Appendix C - ADO.NET Frequently Asked Questions tran.Abort() Index Console.WriteLine("Transaction Aborted!") List of Figures End Try List of Tables End Sub Chapter 21 - Messaging

List of Listings List of SidebarsSub RecieveTransactionalMessages() Public

Dim mq As MessageQueue = New MessageQueue() mq.Path = ".\Private$\mcbTQ" Dim tran As MessageQueueTransaction = _ New MessageQueueTransaction() Try tran.Begin() Dim messages() As System.Messaging.Message messages = mq.GetAllMessages() ' Need a formatter to get the text of the message body. Dim stringFormatter As System.Messaging.XmlMessageFormatter = _ New System.Messaging.XmlMessageFormatter(New String() _

{"System.String"}) Applied Dim index As ADO.NET: Integer Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot Dim msg As System.Messaging.Message Apress © 2003 (928 pages) This text extensive coverage of technology For index = 0provides To messages.Length - ADO.NET 1 including ADO.NET internals, namespaces, classes, and messages(index).Formatter = stringFormatter interfaces, and takes a comprehensive look at XML msg =namespaces messages(index) and classes, and how to integrate both with Console.WriteLine(msg.Label + "," + msg.Body) ADO.NET. Next tran.Commit() Table of Contents Console.WriteLine("Transaction committed!") AppliedCatch ADO.NET—Building Data-Driven Solutions Introduction tran.Abort() Chapter 1 Console.WriteLine("Transaction - ADO.NET Basics Aborted!") ChapterEnd 2 -Try Data Components in Visual Studio .NET End3 Sub Chapter - ADO.NET in Disconnected Environments End Module Chapter 4 - ADO.NET in Connected Environments Chapter 5


Chapter 6


Chapter 7


Chapter 9


Tip Transactional processing is useful when you want to make sure that all messages in a transaction Chapter 8 - Constraints and Data Relations are delivered or none of them are. Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

ADO.NET: Building Data-Driven Solutions EncryptingApplied Messages by Mahesh Chand and David Talbot

ISBN:1590590732

There are certainApress requirements when © 2003 (928 pages)you need to send encrypted messages to make sure the data you're sending is secure. You can use encryption two ways. you technology can encrypt a message itself. Second, This text provides extensiveincoverage of First, ADO.NET you can use queuing services to encrypt a message through the MessageQueue class. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

To encrypt a message, namespaces you can anduse classes, the DestinationSymmetricKey and how to integrate both with property of a message and then ADO.NET. send this message to the queue. The DestinationSymmetricKeyproperty represents the symmetric key used to encrypt application-encrypted messages. Table of Contents TheEncryptionRequired property of MessageQueue sets whether a queue accepts nonencrypted or Applied ADO.NET—Building Solutions encrypted messages. TheData-Driven EncryptionRequired enumeration provides the value of the Introduction EncryptionRequired property, which has three values: Body,None, and Optional. The Body option Chapter - ADO.NET Basics makes 1sure the queue only accepts private (encrypted) messages. The None option means the queue Chapter - Data Components in Visual Studio .NET accepts2 only nonencrypted messages. The Optional option means the queue accepts both encrypted Chapter 3 - ADO.NET in Disconnected Environments and nonencrypted messages. Chapter 4


TheEncryptionAlgorithm property of the Message class represents the type of encryption applied - Handling ADO.NET Events on a message. This property is represented by the EncryptionAlgorithm enumeration, which has Chapter 6 - Integrating XML with ADO.NET three values: None,RC2, and RC4. The value None means no encryption. RC2 is a 64-bit block encryption, Chapter 7 - Data Binding and Windows Forms Data-Bound Controls andRC4 is the stream encryption. The block mode encrypts a block of data at a time, and the stream Chapter 8 - Constraints and Data Relations mode encrypts a bit at a time. Chapter 5

Chapter 9


Chapter - Working the ODBC .NET Data Listing 10 21-10 sends with encrypted messages. AsProvider you can see, it sets the UseEncryption property of a Chapter Message 11 -object StoredtoProcedures activate theand encryption. Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Listing13 21-10: Sending Chapter - Developing a Encrypted Custom DataMessages Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter Try 15 - Using ADO.NET in Xml Web Services

Dim msg As System.Messaging.Message = _ Chapter 16 - ASP.NET Server Controls and Data Binding System.Messaging.Message(titleTextBox.Text) Chapter 17 -New Building Real-World Web Applications MessageQueue1.EncryptionRequired = _ Chapter 18 - Object-Relational Mapping in .NET Messaging.EncryptionRequired.Body Chapter 19 - Mapped Objects: Performance Considerations and Data Binding msg.UseEncryption = True Chapter 20 - COM Interoperability and ADO.NET If (rc4RadioBtn.Checked) Then msg.EncryptionAlgorithm = Messaging.EncryptionAlgorithm.Rc4 Chapter 22 - SQL Server and ADO.NET: Notes on Performance ElseIf (rc2RadioBtn.Checked) Then Appendix A - Relational Databases: Some Basic Concepts msg.EncryptionAlgorithm = Messaging.EncryptionAlgorithm.Rc2 Appendix B - Commonly Used SQL Statements Else Appendix C - ADO.NET Frequently Asked Questions msg.EncryptionAlgorithm = Messaging.EncryptionAlgorithm.None Index End If Chapter 21 - Messaging

List of Figures List of Tables msg.Label = titleTextBox.Text List of Listings msg.Body = bodyTextBox.Text List of Sidebars MessageQueue1.Send(msg)

Catch exp As Exception MessageBox.Show(exp.Message) End Try

Summary


ISBN:1590590732

In this chapter, we covered some basic programming of messaging services. The System.Messaging Apress © 2003 (928 pages) namespace offers much more than we're able to discuss in this chapter. Still, this chapter should give you This text provides extensive coverage of ADO.NET technology a quick jump startincluding on MSMQ using .NET. ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes,by and how to integrate bothLibrary with to work with messaging services. We also discussed the classes provided the .NET Framework ADO.NET. We discussed how to create, delete, and manage queues. Additionally, we discussed how to send and receive normal messages and transaction messages. Finally, we discussed the security, encryption, and authentication issues involved in messaging and the classes provided by the .NET Framework Library to Table of Contents implement messaging. Applied ADO.NET—Building Data-Driven Solutions

Introduction In the next chapter, we cover performance and optimization issues and how to handle these issues when Chapter - ADO.NET Basics working1 with ADO.NET and SQL Server. Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Chapter Applied 22: SQL Server and ADO.NET: Notes on ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) Performance This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and performance has always been as Ever since the early days of relational databases, optimizing database interfaces, and takes a comprehensive look at XML much an art as anamespaces science. Even today, you'll often hear of new "secrets" through professional relationships and classes, and how to integrate both with that take on the air of furtive backalley exchanges more reminiscent of a Le Carré novel than a sober ADO.NET. discussion between colleagues. This chapter discusses some SQL Server and ADO.NET performance issues. It also discusses some best practices to make sure you get the most out of your code. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Improving SQL Server Performance

Introduction

Chapter 1 - ADO.NET Basics The following sections provide some of the "back-alley" secrets we've accumulated over the years, as well Chapter 2 of - the Datamore Components in Visual Studio .NET as some methodical approaches for examining your database and determining the best course Chapter 3 to- achieve ADO.NETthe in Disconnected Environments of action best performance. Chapter 4 - ADO.NET in Connected Environments Chapter 5

- Handling ADO.NET Events Using Indexes

Chapter 6


Chapter 7 selecting - Data Binding and Windows Data-Bound Properly and managing yourForms indexes can have Controls the single biggest impact on performance using Chapter any database-and 8 - Constraints Microsoft and Data SQLRelations Server is no different. Indexes are like little optimized tables that organize

the data most commonly use so that you can find rows in the main table optimally. Chapter 9 you'll - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

To manage the indexes on a table, simply right-click the table in Enterprise Manager, choose All Tasks from the menu that pops up, and then select Manage Indexes (see Figure 22-1).



Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Figure 22-1: The Manage Indexes menu in Enterprise Manager


From the dialog box that appears, you can manage any of the tables in any of the databases running in the List of Figures current instance of Microsoft SQL Server (see Figure 22-2). You can change databases by choosing a List of Tables

different database from the Database drop-down list, or you can change the table you're managing your indexes on by choosing another table from the Table drop-down list.

List of Listings

List of Sidebars


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5

- Handling ADO.NET Events Figure The Manage dialog box Chapter 6 - 22-2: Integrating XML withIndexes ADO.NET Chapter 7


Chapter 9


Once you have the database and table selected that you would like to manage the index on, the current Chapter 8 - Constraints and Data Relations indexes that exist on the table display in the Existing Indexes area. Chapter - Working ODBC .NET To add10 a new index with to thethe table, click theData NewProvider button at the bottom of this dialog box. This opens the Create Chapter 11 Stored Procedures and Views New Index dialog box (see Figure 22-3). Having a good understanding of this dialog box and its implications Chapter 12to- Oracle, and Other application. .NET Data Providers is critical creatingSQLXML, a top-performing Determining which columns you should index in different Chapter 13will - Developing Custom Data Providerso for now you'll focus on the options for determining the contexts be covereda later in this chapter, Chapter behavior 14of - the Developing index you'd Database like toWeb create. Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 22-3: The Create New Index dialog box Checking the Unique Values box tells SQL Server that this index will be unique. If you're creating an index on a single-column identity column or any other type of single column where you know the value will always be unique, check this box. The index then knows that once it has found the item it's looking for, it shouldn't look any further, which makes for a faster index.

The real value of this option comes into play when dealing with a multiple-column index that, when Applied ADO.NET: Building Data-Driven Solutions combined, produces a unique value. For example, a complicated join table may not have any single column Mahesh Chand David Talbotof two of theISBN:1590590732 that represents aby unique value, butand a combination columns is unique. Apress © 2003 (928 pages)

The Pad Index and Filltext Factor options are related. When you buildtechnology an index, the index pages contain as This provides extensive coverage of ADO.NET including internals, ifnamespaces, classes,add anddata to the table, then it takes a little much data as possible by ADO.NET default. However, you subsequently interfaces, and takes a comprehensive look scratch. at XML Setting the Fill Factor option allows you longer because new index pages have to be created from namespaces and classes, and how to integrate both with to control how much spare space is left in each index page; a frequently updated table might have a Fill ADO.NET. Factor option as low as 20 or even 10 percent. An index with a lower Fill Factor takes up more space, but it provides better performance. Note, though, that once the spare space is fully used, subsequent index Table of are Contents pages completely filled as if their Fill Factor was zero-regardless of what the setting was when the index Applied was created. ADO.NET—Building At this point,Data-Driven you shouldSolutions recompile the index to recover the performance enhancement. At installation, the default Fill Factor option for a server is set at 0, meaning each index page is completely Introduction filled, but can alter this either through the SQL Server Enterprise Manager Server Properties dialog box Chapter 1 you - ADO.NET Basics or by using the sp_configure system stored procedure. Chapter 2 - Data Components in Visual Studio .NET Chapter 3


The Pad Index option performs a similar function and in fact uses the same percentage as the Fill Factor - ADO.NET in Connected Environments option. SQL Server indexing uses an indexing method called b-trees, which means the index contains a Chapter 5 - Handling ADO.NET Events number of nodes where each node acts as a parent to two or more subnodes. The lowest pages of the Chapter 6 - Integrating XMLare with index, beyond which there noADO.NET further nodes, are called leaf pages, and it is these that the Fill Factor Chapter 7 Data Binding and Windows Formsspare Data-Bound Controls option affects. Padding the index allocates space in the intermediate nodes, allowing for much Chapter - Constraints Data data Relations greater8expansion to theand table's than the Fill Factor option alone would support. Typically, however, Chapter ADO.NET Handling setting 9the-Fill Factor Exception option provides enough optimization, and you should pad the index only in high-use Chapter 10 - Working with the ODBC .NET Data Provider scenarios. Chapter 4


The Clustered Index option internally data in a way that is optimal for a number of queries, Chapter 12 - Oracle, SQLXML, and Othersorts .NETthe Data Providers especially those involving GROUP BY,ORDER BY,BETWEEN, or join clauses. A clustered index also provides a large boost for queries that involve aggregate functions such as MIN or MAX.



Chapter 15 -indexes Using ADO.NET in on Xmlcolumns Web Services Clustered don't help that contain data with little variability such as bit columns or Chapter 16 ASP.NET Server Controls Data Bindingrepresenting states. Unless the country goes on a huge columns that join to something finiteand such as values Chapter 17 Building Real-World Web Applications annexation binge, this number will remain relatively small compared to other things that are better Chapter 18 - for Object-Relational candidates your clusteredMapping index. in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

You can only one clusteredand index on any given table, so think about what you want to take advantage Chapter 20have - COM Interoperability ADO.NET of the potential performance boost. This may sound trivial; however, if you closely examine a table, you'll see a number of options. You'll have to determine which ones your queries will use the most.



Appendix - Relational Databases: Basic Concepts The Do A Not Recompute StatisticsSome option comes with a warning that it is not recommended. In almost all Appendix B - Commonly Used SQL Statements circumstances, heed this warning or you could get some unexpected results. The only situation where you Appendix C - this ADO.NET should use optionFrequently is where aAsked tableQuestions is read only and will never be altered. Index List of Figures

Choosing Which Columns to Index

List of Tables

List of Listings Knowing which columns to index is as important as knowing what options to use when indexing them. This List Sidebars is aofgood place to start: Any column you frequently query is probably a good candidate for an index.

The best candidates for indexes are usually the primary keys of your tables. The reason for this is when you're doing a multiple table join, you'll usually do the join on your primary key. If most of your queries use a particular column, then it's probably optimal to make that column a clustered index. It's never necessary to create an index for your primary keys because of the nature of how SQL Server stores data relating to autonumbered primary keys. How SQL Server Stores Your Data SQL Server works well when storing data. Its overall goal is to make sure that when a row is inserted, it can be placed physically between rows above and below your primary key in terms of sort order. By ensuring that the rows are stored in the order of your primary key, primary key searches are very fast.

For tables where you're providing your own value for your primary key, you'll want to use table padding. Applied ADO.NET: Building Data-Driven Solutions

ISBN:1590590732 by Mahesh Chand and David Talbot If your table uses an auto-numbered primary key, your records will automatically be in the correct order © 2003 (928ofpages) as you insert Apress them because the auto numbering that SQL Server uses to store your data. In this case, it's not This beneficial to use table padding. text provides extensive coverage of ADO.NET technology


Also, when choosing what columns to index, remember that you only get one clustered index. The clustered index groups and orders your index in a manner that it can quickly find what is being queried against. Table of Contents

Also, don't waste your clustered index on a finite state column. This includes bits and numbers with little variance (for example, an integer between 1 and 10). The clustered index shines on columns with broad Introduction variances in data, not in situations where most of the data in the column is the same from row to row. Applied ADO.NET—Building Data-Driven Solutions Chapter 1

- ADO.NET Basics

Chapter 2


Understanding the SQL Server Profiler - ADO.NET in Disconnected Environments

Chapter 3 Chapter 4

- ADO.NET in Connected Environments You can learn quite a few things about how to optimize your database by using the SQL Server Profiler. The

Chapter 5 - Handling ADO.NET SQL Server Profiler allows youEvents to see what the database is doing, when it is doing it, and how long it takes. Chapter 6 - Integrating XML with ADO.NET

You can SQLand Server Profiler fromData-Bound the Microsoft SQL Server submenu in the Start menu or from Chapter 7 launch - Data the Binding Windows Forms Controls the Tools of Enterprise Manager. Once you've launched the SQL Server Profiler, you can start a new Chapter 8 menu - Constraints and Data Relations trace by9 choosing FileException ØNewØTrace. This opens the Trace Properties dialog box (see Figure 22-4). Chapter - ADO.NET Handling Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure 22-4: The Trace Properties dialog box

Once you've launched the Trace Properties dialog box, you'll see a number of important options. If you intend on being able to run the optimizer (which can automatically perform a number of optimizations on your database), you'll need to save the output to a trace file. You can do this by checking the Capture to File box and then choosing a file by clicking the folder icon to the right of the box. The Events tab allows you to manually choose the events you'd like to include in the trace. These events include table scans, stored procedures being called, and more. It's worth your time to look through this menu and identify the types of events in which you're interested. The Data Columns tab provides you with the ability to choose the kind of information you want captured

when each of the selected events occurs. Some of the options included are the Application Name, CPU Applied ADO.NET: Building Data-Driven Solutions Time Used, IO, and Duration. by Mahesh Chand and David Talbot

ISBN:1590590732

Apress © 2003 (928 pages) The Filters tab allows you to choose the items you would like excluded from your trace. Generally, you don't need this tab when working againstextensive a development database whose traffic is limited to your usage, but it's This text provides coverage of ADO.NET technology ADO.NET namespaces, classes, databases and helpful in buildingincluding a trace against a internals, large server that has multiple on it. In other words, it's helpful and takes a comprehensive look at XML to be able to filterinterfaces, out the "noise." namespaces and classes, and how to integrate both with ADO.NET.

Once you've started your trace, you'll be able to watch the activity on your database in real time and understand how long each query and stored procedure takes to execute (see Figure 22-5). Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure 22-5: The SQL Server Profiler with a trace running



If you're17watching a trace on a live system, you should be able to quickly identify any stored Chapter - Building Real-World Webproduction Applications procedures that are taking a Mapping long timeinto.NET run by looking at the Duration column. Any stored procedure Chapter 18 - Object-Relational taking longer than 50 milliseconds is a potential danger and to your application's scalability. Chapter 19 - Mapped Objects: Performance Considerations Data Binding Chapter 20 - COM Interoperability and ADO.NET

Optimizing Automatically with the SQL Server Profiler



The SQLA Server Profiler also provides outstanding Appendix - Relational Databases: Some an Basic Concepts tool that can automatically optimize your database for you. Database veterans are SQL probably cringing as they read this after having been burned by one of the Appendix B - Commonly Used Statements

variety of applications that promised to do this and delivered marginal results. However, SQL Server's Index Tuning Wizard provides most of the optimization that applications need as long as you understand a few Index caveats. Appendix C - ADO.NET Frequently Asked Questions List of Figures

List of Tablesit's important to keep in mind that the Index Tuning Wizard does nothing for optimizing the Foremost, List of Listings database for queries contained in stored procedures. This is a bit of a problem given that it's a good List of Sidebars practice to keep all of your database queries wrapped in stored procedures for optimal performance.

Note For more information about SQL Server performance, see Brad M. McGehee's site at www.sqlserver-performance.com. You can also refer to William R. Vaughn's books, notably ADO.NET and ADO Examples and Best Practices for VB Programmers, Second Edition (Apress, 2002) or the classic Hitchhiker's Guide to Visual Basic and SQL Server (Microsoft Press, 1998), which discusses Visual Basic 6, SQL Server 7, and SQL Server 2000, Microsoft Data Engine (MSDE), and ADO 2.0. Fortunately, there are some workarounds to this particular problem. You can copy and paste queries from your stored procedures into the Query Analyzer and have it assess the load you're putting on the database and make an informed decision on what indexes should be added.

Once you've pasted your query into the Query Analyzer, choose Query Ø Perform Index Analysis, and the Applied ADO.NET: Building Data-Driven Solutions Query Analyzer will use the SQL Server Profiler to show you the best course of action (see Figure 22-6). by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732


Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Figure 22-6: The Query Analyzer's recommendations for the current query Chapter 1 - ADO.NET Basics Chapter 2


If the Query Analyzer has recommendations on what you should do, a second dialog box will pop up and - ADO.NET in Disconnected Environments ask if you want it to automatically implement the recommendations. Often, it recommends adding an index Chapter 4 - ADO.NET in Connected Environments to a particular column that is causing a table scan because table scans take significantly longer to run than Chapter 5 - Handling ADO.NET Events indexed queries (see Figure 22-7). Chapter 3

Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - 22-7: ASP.NET and recommendation Data Binding Figure TheServer QueryControls Analyzer's to create an index that would help the query run Chapter 17 Building Real-World Web Applications faster Chapter 18 - Object-Relational Mapping in .NET

You can attachObjects: the SQLPerformance Server Profiler to run a trace your production database to identify Chapter 19also - Mapped Considerations andagainst Data Binding stored procedures that are taking longer to execute than you would like. Then, launch the wizard and Chapter 20 - COM Interoperability and ADO.NET choose21 Profile the Performance of a Stored Procedure; the tool will test that particular stored procedure Chapter - Messaging and recommend what you do to optimize performance. Chapter 22 - SQL Server and can ADO.NET: Notes on its Performance Appendix A - Relational Databases: Some Basic Concepts

It's largely a matter of personal preference as to how you want to work to improve the performance of your stored procedures. Although the wizard makes suggestions, you don't have the opportunity to tweak and Appendix - ADO.NET Frequently Asked alter theCstored procedure the way youQuestions do with the Query Analyzer. Appendix B - Commonly Used SQL Statements Index List of Figures

Optimizing Your Transact-SQL Queries for Performance

List of Tables

List of can Listings You tune your Transact-SQL queries and stored procedures for performance in a number of ways. List of Sidebars Think of your queries as asking the database a question and think of the optimizations you make on the

query as asking the question in a way that requires the database less thought. Listing 22-1 shows an inefficient query that you can optimize. Listing 22-1: The Query from SelectVideosCheckedIn, Not Optimized SELECT VideoTapeID, Title, Description FROM VideoTape WHERE VideoTapeID NOT IN ( SELECT VideoTapeID FROM VideoCheckOut as vco WHERE VideoTapeID NOT IN (SELECT VideoTapeID From VideoCheckIn as vci WHERE vco.VideoCheckOutID=vci.VideoCheckOutID) )


ISBN:1590590732

The query in Listing 22-1© took 15 seconds to return 42,000 rows from the VideoStore2 database available in Apress 2003 (928 pages) the downloadableThis code for this book. Most this is the required to pipe out that many rows to the text provides extensiveofcoverage of time ADO.NET technology Query Analyzer. But even with factoring that in, there's a way to shave including ADO.NET internals, namespaces, classes, and a second off the query time. Figure interfaces,plan andof takes a comprehensive look at XML 22-8 shows the execution Listing 22-1. namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Figure 22-8: The estimated execution plan of the query in Listing 22-1

Chapter 4

- ADO.NET in Connected Environments By using IN to test the subqueries, SQL Server has to do a comparison to make sure that the Chapter 5 NOT - Handling ADO.NET Events

VideoTapeID doesn'tXML match atADO.NET each level of the subquery. To understand what SQL Server is doing to Chapter 6 - Integrating with perform7 this query, it's helpful to be able to see the execution path and examine it for comparisons and Chapter - Data Binding and Windows Forms Data-Bound Controls table scans that you can eliminate. Chapter 8 - Constraints and Data Relations Chapter 9


You can view this in the Query Analyzer by choosing Query Ø Display Estimated Execution Path. This tool is an especially powerful weapon in the war against inefficient queries.


Chapter Next to12 each - Oracle, item inSQLXML, the execution and Other path.NET is a Data cost in Providers terms of the percentage of the overall execution time

(always13adding up to 100 percent). AsProvider you follow the execution path and move your mouse over each item, Chapter - Developing a Custom Data you should attention to a fewWeb key Applications items in theusing pop-up text. The three most critical factors to pay Chapter 14 - pay Developing Database ASP.NET attention are Estimated of Executes, Chapter 15to- Using ADO.NETNumber in Xml Web Services Estimated CPU, and Estimated IO. Chapter 16 - ASP.NET Server Controls and Data Binding

Estimated Number of Executes lets you know how many times the comparison will be performed. If you can think of a way to keep the logic of your query and still reduce the number of times this comparison must be Chapter 18 - Object-Relational Mapping in .NET performed, you can have an excellent impact on performance. Chapter 17 - Building Real-World Web Applications


Chapter The Estimated 20 - COMCPU Interoperability and Estimated and IO ADO.NET columns let you know how much CPU usage and disk IO is resulting

for a single in the process of executing your stored procedure. Chapter 21 - step Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Using the information derived from the estimated execution plan, you can identify a few areas that are ripe for optimization. You can significantly reduce the table scan icon that is taking up 60 percent of the Appendix B - Commonly Used SQL Statements execution time if you use a narrowing item in the WHERE clause. Appendix A - Relational Databases: Some Basic Concepts Appendix C - ADO.NET Frequently Asked Questions

Index One of the biggest impacts you can have on the speed of your query execution is keeping the result set as List small of Figures as possible. To this end, you can modify the SelectVideosCheckedIn stored procedure to include List a simple of Tables way to reduce the number of rows that must be compared to the subquery. In this case, narrowing

theofresults based upon the CategoryID vastly reduces the number of rows that will be analyzed and List Listings returned. Listing 22-2 lists an optimized version of SelectVideosCheckedIn. List of Sidebars Listing 22-2: An Optimized Version of the SelectVideosCheckedIn Query SELECT VideoTapeID, Title, Description FROM VideoTape WHERE CategoryID=5 AND VideoTapeID NOT IN ( SELECT VideoTapeID FROM VideoCheckOut as vco WHERE VideoTapeID NOT IN (SELECT VideoTapeID From VideoCheckIn as vci WHERE vco.VideoCheckOutID=vci.VideoCheckOutID) )


ISBN:1590590732

Another effect of narrowing the results from the VideoTape table before performing the subquery comes Apress © 2003 (928 pages) from the Estimated Number of Executions that are now expected to run on the Table Spool step and its text provides extensive coverage of ADO.NET technology related substeps.This Without narrowing the results by CategoryID first, this step executed 42,000 times-one for including ADO.NET internals, namespaces, classes, and each row in the database. With the VideoTape table narrowed by CategoryID, this number drops to a few interfaces, and takes a comprehensive look at XML thousand, providing an enormous boost toand thehow performance ofboth the SQL namespaces and classes, to integrate with statement. Figure 22-9 shows the execution plan ofADO.NET. Listing 22-2. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4 - 22-9: ADO.NET Connectedexecution Environments Figure Theinestimated plan of the query in Listing 22-2 Chapter 5 - Handling ADO.NET Events

A second you can reduce the number of rows returned is to use SELECT TOP to reduce the Chapter 6 strategy - Integrating XML use withto ADO.NET number7 of-rows expect be returned. can provide an enormous performance boost, especially in Chapter Data you Binding andtoWindows FormsThis Data-Bound Controls situations where you don't care precisely what records from the larger result set are required. - Constraints and Data Relations

Chapter 8

Chapter 9 - ADO.NET Handling An example of whereException this behavior is beneficial is in an unordered queue situation. For example, if you had Chapter 10 Working with the ODBC .NET to Data Provider a table that tracks tasks for employees perform and you wanted a query that would return 10 tasks for Chapter 11 - Stored Procedures Views the employee to do, you couldand write a query like this one: Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 TOP - Developing a Custom Data FROM Provider SELECT 10 TaskID, Name Tasks WHERE Assigned=0 Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

The performance increase Chapter 16 - ASP.NET Server comes Controlsfrom and two Dataelements. Binding First, the number of rows that have to be piped across 17 the-network significantly less. Second, the query can stop running as soon as it has any 10 Chapter Building is Real-World Web Applications records18that meet the criteria.Mapping in .NET Chapter - Object-Relational Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

If the query had to have the tasks in some type of order, such as Date Due column, then the query would lose the benefit of being able to stop executing as soon as it identified 10 items meeting the criteria. Adding Chapter 21 -BY Messaging an ORDER clause forces the query to completely execute to return the top 10 items in the correct order Chapter 22 Server and ADO.NET: Notes on Performance in which youSQL expect them. Chapter 20 - COM Interoperability and ADO.NET


Understanding the execution plans of your queries can help you devise effective strategies for producing Appendix B - Commonly Used SQL Statements better stored procedures. Appendix C - ADO.NET Frequently Asked Questions Index

Avoiding Excessive Stored Procedure Recompilation


One the reasons stored procedures are faster than simply executing SQL directly against the database is List of of Listings thatofstored procedures are interpreted and compiled into a structure that SQL Server can execute List Sidebars efficiently. The danger that comes from this is excessive recompilation if SQL Server thinks something has changed in your stored procedure. A simple way to avoid excessive recompilations is to keep all of your variable and temporary table declarations together in your stored procedure. Some types of declarations, such as the creation of a temporary table, cause the stored procedure to recompile, but if it surrounded by other such statements, they will all be compiled at the same time instead of breaking execution as each statement is compiled. Another cause of your stored procedure being frequently recompiled is if the contents of the tables the stored procedure is querying change frequently. If you have a table that is constantly changing, using sp_executesql can keep your stored procedure from recompiling (see Listing 22-3). The downside of this particular approach is that SQL Server won't be able to cache the execution plan of the query you run in

your stored procedure.


by Mahesh Chand and David Talbot a DatabaseISBN:1590590732 Listing 22-3: Using sp_executesql to Execute Query Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology EXEC dbo.sp_executesql N' including ADO.NET internals, namespaces, classes, and SELECT VideoTapeID, Title, WHERE interfaces, and takes Description a comprehensive FROM look at VideoTape XML VideoTapeID NOT IN namespaces and classes, and how to integrate both with ADO.NET. ( SELECT VideoTapeID FROM VideoCheckOut as vco WHERE VideoTapeID NOT IN (SELECT VideoTapeID From VideoCheckIn as vci WHERE Table of Contents vco.VideoCheckOutID=vci.VideoCheckOutID) Applied ADO.NET—Building Data-Driven Solutions )' Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3 -what ADO.NET in procedures DisconnectedinEnvironments To identify stored your database are recompiling excessively, use the SQL Server Chapter Profiler4and - ADO.NET make sure in Connected you have the Environments SP:Recompile event selected. The SQL Server Profiler shows you Chapter when each 5 - recompilation Handling ADO.NET occurs. Events If you're able to identify any stored procedures that recompile often, you'll

have an6 excellent placeXML to start your database performance. Chapter - Integrating with tuning ADO.NET Chapter 7


- Constraints Avoiding Locksand Data Relations

Chapter 8 Chapter 9

- ADO.NET Exception Handling To avoid threadswith accessing the.NET same resource at the same time, SQL Server has a locking system. If Chapter 10two - Working the ODBC Data Provider

your CPU IO are low your database is performing slowly, it's likely you have some bad Chapter 11 -usage Storedand Procedures andbut Views locking12 conditions Chapter - Oracle,occurring. SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

If you have a stored procedure that needs frequent recompilation, make sure you include the table owner in all of your statements. When a stored procedure is being recompiled, it's in a locked state and can't be Chapter 15 - Using ADO.NET in Xml Web Services called by another process until it has finished recompiling. If it has to look up who owns each table as it Chapter 16recompile, - ASP.NET it'll Server does the takeControls longer. and Data Binding Chapter 14 - Developing Database Web Applications using ASP.NET


Also, avoid cursors at all costs. in A cursor Chapter 18 - using Object-Relational Mapping .NET allows row-by-row processing on a result set. Sometimes a cursor is but it can put a lock on the table while executes. You can rewrite most queries that Chapter 19necessary, - Mapped Objects: Performance Considerations anditData Binding use a cursor using either a CASEand clause or at least a TABLE variable if you're using SQL Server 2000. Chapter 20 - COM Interoperability ADO.NET Chapter 21 - Messaging

Finally, only use transactions when you need to-and keep transactions short. Because a transaction can't have any data modified outside of the transaction while it's occurring, it'll lock almost everything it touches. If Appendix A - Relational Databases: Some Basic Concepts you think through the execution of your transaction and come up with any way to keep your transactional Appendix - Commonly Used SQL integrity Bwithout actually using a Statements transaction, then you can reduce the number of locks that occur. Chapter 22 - SQL Server and ADO.NET: Notes on Performance


Designing Your Tables for Optimal Performance

List of Figures

List Tables the best performance from your database, you'll need to start thinking about performance as To of achieve List Listings youofdesign your table schema. In every step of the process, think about how you'll query the data in the List of Sidebars table and how you'll run updates on it. Unfortunately, sometimes you'll have to break away from clean

design and choose one that is not as clean as you would like it to be to achieve optimal performance. A common myth in designing a database for performance is that every table must have a primary key. In general, it's a good idea for every table to have a primary key-unless the primary key will never be used. A good example of this is a join table that sits between two tables and expresses a relationship between the two. Adding an extra column to a table that represents a many-to-many relationship is like having a fifth wheel on your car-it won't break anything, but it might hurt your gas mileage just a little. Figure 22-10 shows a join table.


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET. Figure 22-10: A join table that doesn't need a primary key Table oftable Contents In the structure shown in Figure 22-10, the VideoTapeType table doesn't need a primary key. If you Applied Data-Driven Solutions added ADO.NET—Building another VideoTapeTypeID column as an autonumbered primary key, it would be completely Introduction superfluous and add a useless piece of data to the database. Chapter 1 - ADO.NET Basics

If performance absolutely critical down to the last cycle and you're willing to commit to an unclean Chapter 2 - DataisComponents in Visual Studio .NET

database design, denormalizing your data can be an effective means of achieving that performance. This - ADO.NET in Disconnected Environments type of situation comes up fairly often when dealing with a system that allows people to log in and search Chapter 4 - ADO.NET in Connected Environments for companies. In this situation, you're working on a database that has two types of companies-companies Chapter 5 - Handling ADO.NET Events with people who can log into your system and companies that are just searchable data. It'll provide better Chapter 6 - Integrating XML with ADO.NET performance for the companies that can log in to have the companies that can't in a separate table. The Chapter 7 - Data Binding and Windows Forms Data-Bound Controls reason for this is it's likely that the number of companies that can't log in is significantly greater than those Chapter 8 but - Constraints and Data Relations that can, at the same time you'll likely be doing many more queries on the companies that can log in. It's Chapter 9 ADO.NET Exception Handling definitely a convoluted situation and bad practice to track the same data in two places. However, if you can Chapter 10amount - Working with the ODBC .NET Data keep the of data in one table that willProvider be frequently accessed small to the detriment of good design, Chapter 11 Stored Procedures and Views it can help quite a bit. Chapter 3


Checking the Size of Database Pages

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter - Using ADO.NET Xml Web stored Services In SQL15 Server 2000, data isininternally as a collection of 8KB pages. The more rows that can be Chapter 16 a - ASP.NET Server Controls and all Data Binding stored on single 8KB page, the faster queries run on the database will be and the less space the table Chapter will take17up. - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

A simple way to find out how many bytes each row takes up is to look at the Size column in design view. If you add up the size of each of these columns and it's perfectly divisible by 8KB, then you have a perfect Chapter 20 - COM Interoperability and ADO.NET situation where no space will be wasted in the pages. This doesn't mean you should intentionally make your Chapter 21 - Messaging tableslarger just to be divisible by 8KB-but in general smaller tables are better for your application's design. Chapter 22 - SQL Server and ADO.NET: Notes on Performance If you have a table with more than 10 columns, make sure your requirements are best served by what Appendix A - Relational Databases: Some Basic Concepts you're doing. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding


Appendix Database C -page ADO.NET size isFrequently one of theAsked reasons Questions why it's generally better to have multiple small tables as opposed

to a denormalized table that contains a large number of columns. Index List of Figures

Understanding Denormalization

List of Tables

List of Listings

The List of opposite Sidebars of normalization is denormalization, which essentially amounts to creating large, flat table structures that have all of the columns you need on a single row. Denormalized tables are generally used for reporting, for derived tables, or for data warehousing. In general, it's not recommended to use a denormalized schema unless it's for one of those reasons-generally in a data warehouse or "business intelligence" environment. The performance benefit of these tables comes from the fact that the database doesn't need to join multiple tables together. Denormalization is useful for situations where you need most of the data that's in the table. If a denormalized table has 40 columns, and you really only need the data in two of the columns the majority of the time, you're likely better off just using a regular normalized table schema to achieve optimal performance.

Understanding Dangers ofData-Driven Database Design Slippage Appliedthe ADO.NET: Building Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

You have to maintain a fine balance when creating a database schema between three main elements: This text provides extensive coverage of ADO.NET technology Clean normalized design including ADO.NET internals, namespaces, classes, and

Performanceinterfaces, and takes a comprehensive look at XML


Speed of development

If you're designing a large, complicated application, a good normalized design is probably the way to go. If scalability is the prime consideration, then performance comes first. If the application you're developing is Applied ADO.NET—Building Data-Driven Solutions small and doesn't have scalability requirements, obviously speed of development is at the top of your list.


Chapter 1 -make ADO.NET Above all, sureBasics you're designing the application the way it's needed, and as with all professional Chapter applications, 2 - Data make Components the right tool in Visual for theStudio job and .NET avoid architectural "gold plating" (creating a system that is

beautifully to ainprogrammer but doesn't solve the business problem any better than a less-geeky Chapter 3 -geeky ADO.NET Disconnected Environments solution). peopleinwho pay yourEnvironments salary probably don't know or care that your application uses an Chapter 4 The - ADO.NET Connected absolutely normal form. Chapter 5 -perfect Handling ADO.NET Events Chapter 6


With this consideration, you have to be careful when you start slipping from clean design because without - Data Binding and Windows Forms Data-Bound Controls discipline it can become a "slippery slope." Sometimes doing the "wrong" thing because it's fast can make Chapter 8 - Constraints and Data Relations development slow later as you work to cover up the sins of your past. Always think in terms of both Chapter 9 lazy - ADO.NET Exceptionlazy Handling longterm and short-term (described in Chapters 18 and 19). Chapter 7


AppliedADO.NET ADO.NET: Building Data-Driven Solutions Understanding Performance Issues and Using Best ISBN:1590590732 by Mahesh Chand and David Talbot Practices Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET The following sections discuss some performance strategies and technology best practices when working with including ADO.NET internals, namespaces, classes, and ADO.NET. interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Selecting Data Providers

Many data providers are available to work with a single database, and selecting a best-suited data provider is the first step to designing performance-oriented, datadriven solutions. Some of the common data Applied ADO.NET—Building Data-Driven Solutions providers discussed in this book are Sql, OleDb, ODBC, OracleClient, and SQLXML.


Chapter 1 -provider ADO.NETacts Basics Each data in a different way because of its internal architecture and the way it's designed. Chapter 2 - Data Visual Studio .NET drivers, and the OleDb data provider uses OLE DB For example, theComponents ODBC data in provider uses ODBC Chapter providers 3 to - ADO.NET connect to in Disconnected different dataEnvironments sources. Each of these technologies works differently internally. Chapter 4


Selecting a- data provider depends on your application's requirements. This section discusses the different Handling ADO.NET Events scenarios and the best solutions.

Chapter 5 Chapter 6


Chapter - Data Windows you Forms To work7 with SQLBinding Serverand databases, canData-Bound use any ofControls these three data providers: Sql, OleDb, and Chapter andwith Data Relations ODBC.8But- Constraints when working SQL Server 7.0 or later databases, the Sql data provider is the best choice. Chapter 9 data - ADO.NET Exception No other provider can beatHandling the performance of the Sql data provider in this case. The Sql data Chapter 10can - Working thefaster ODBCdata .NETaccess Data Provider provider providewith much than the OleDb and ODBC data providers. That said, the Chapter Sql data 11provider - Storedisn't Procedures the bestand choice Views to work with SQL Server 6.5 or prior versions of SQL Server. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

When working with Access databases, OleDb is the obvious choice. You can even use ODBC data providers, but OleDb provides better performance.



Chapter 15 - data Usingprovider ADO.NETisin Xml Web Services The ODBC useful when your application needs to access an ODBC data source or there Chapter 16 ASP.NET Server Controls and Data aren't OleDb or other providers available. ForBinding example, if you need to access Excel or text data sources, Chapter - Building Real-World Web Applications you can17simply do this using ODBC data sources. Chapter 18 - Object-Relational Mapping in .NET

Now let's your application needs to access an Oracle database. There are different ways you can work Chapter 19 say - Mapped Objects: Performance Considerations and Data Binding with Oracle databases. You can and useADO.NET the ODBC data provider. Microsoft already has released an Oracle Chapter 20 - COM Interoperability

.NET data provider called OracleClient. Oracle offers another .NET provider developed for Oracle databases. Besides these three data providers, CoreLab offers an Oracle .NET data provider called Chapter 22 - SQL Server and ADO.NET: Notes on Performance OraDirect. So, now the question is this: Which one do you choose? Obviously, using an Oracle .NET data Appendix A - Relational Databases: Some Basic Concepts provider (either Microsoft, Oracle, or CoreLab) is better than using an ODBC data provider to access Appendix B - Commonly Used SQL Statements Oracle databases. Performance-wise, the Oracle data provider is faster than the ODBC data provider Appendix C - ADO.NET Frequently Asked Questions because there's no overhead ODBC layer. Chapter 21 - Messaging

Index

List ofNote Figures The .NET Framework 1.1 (or Visual Studio 2003) installs the Oracle and ODBC data providers.

The OleDb, Sql, Odbc, and Oracle data providers are defined in the System.Data.OleDb, List of Tables System.Data.SqlClient,System.Data.Odbc, and System.Data.OracleClient List of Listings namespaces (respectively). List of Sidebars Choosing from different Oracle .NET data providers depends on your options. Microsoft's Oracle .NET data provider is available free as a part of ADO.NET. If you want to use a third-party data provider such as OraDirect, you need to pay for it. So, what's the solution when you need to work with different databases? Developing custom data access code is definitely a good idea. A custom data provider can consume all data providers to find out the best solution. Because all data providers implement ADO.NET interfaces, you can write some generic code based on the interfaces that will work with any data provider. The following section shows you how to write a generic data access component that utilizes multiple data providers to give you the best options.

Writing a Generic Data Access Component Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

In this section, you'll create a simple generic data access class that allows you to select a DataAdapter Apress © 2003 (928 pages) at runtime. Based on the similar theory, you can extend this class by adding other common functionality to This text provides extensive coverage of ADO.NET technology it. including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Listing 22-4 lists the generic class. As youand canhow see,tothis code uses to create a connection and namespaces and classes, integrate both interfaces with DataAdapter objects. This class has two methods: GetConnection and GetDataAdapter. The ADO.NET.

GetConnection method returns an IDbConnection object created using different data providers based on the connection type and connection string passed in the method. The code also provides Table of Contents functionality for the Sql, OleDb, ODBC, and Oracle data providers. Applied ADO.NET—Building Data-Driven Solutions

Listing 22-4: Generic Data Access Class Introduction Chapter 1

- ADO.NET Basics

Chapter 2 - Data Components Visual Studio class .NET ' Generic Data Access incomponent Chapter 3 Class - ADO.NET in Disconnected Environments Public GenericDataAccessComp Chapter 4 - ADO.NET in Connected Environments = Nothing Private idbConn As IDbConnection Chapter Private 5 - Handling idbAdapter ADO.NETAs Events IDbDataAdapter = Nothing

Private dbAdapter As DbDataAdapter = Nothing Chapter 6 - Integrating XML with ADO.NET ' Default type Forms exposed through Chapter 7 - Data connection Binding and Windows Data-Bound Controls ' ConnectionType Chapter 8 - Constraints and Data Relations ' 19 - -Sql; 2 -Exception OleDb,Handling 3 - Odbc Chapter ADO.NET ' 410- -Oracle Chapter Working with the ODBC .NET Data Provider Private DefConnType As Int16 = 1 ' Default connection string exposed through Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers ' ConnString property Chapter 13 - Developing a Custom Data Provider Private DefConnStr As String Chapter 11 - Stored Procedures and Views


Public Sub GenericDataAccessComp()

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter - Building Real-World Web Applications End17Sub Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding ' GetConnection returns IDbConnection Chapter 20 - COM Interoperability and ADO.NET Public Function GetConnection(ByVal connType As Integer, _ Chapter ByVal 21 -connString Messaging As String) As IDbConnection ChapterSelect 22 - SQLCase ServerconnType and ADO.NET: Notes on Performance

Case 1 Appendix A - Relational Databases: Some Basic Concepts OleDb Data Provider Appendix B -'Commonly Used SQL Statements = New SqlConnection(connString) Appendix C -idbConn ADO.NET Frequently Asked Questions Case 2 ' Sql Data Provider List of Figures idbConn = New OleDbConnection(connString) List of Tables Case 3 List of Listings ' ODBC Data Provider List of Sidebars idbConn = New OdbcConnection(connString) Case 4 ' Oracle data provider idbConn = New OracleConnection(connString) Case Else Exit Function End Select Return idbConn End Function Index

' GetDataAdapter returns IDbDataAdapter Public Function GetDataAdapter(ByVal connType As Integer, _

ByVal conn As IDbConnection, ByVal sql As String) _ Applied ADO.NET: Building Data-Driven Solutions As IDbDataAdapter ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages) Select Case connType Case 1 This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and ' OleDb Data Provider interfaces, and takes a comprehensive look at XML idbAdapter = New SqlDataAdapter(sql, conn) namespaces and classes, and how to integrate both with Case 2 ADO.NET.

' Sql Data Provider idbAdapter = New OleDbDataAdapter(sql, conn) Table of Contents Case 3 Applied ADO.NET—Building Data-Driven Solutions ' ODBC Data Provider Introduction idbAdapter = New OdbcDataAdapter(sql, conn) Chapter 1 Case - ADO.NET Basics 4 Chapter 2 -'Oracle Data Components data provider in Visual Studio .NET = New OracleDataAdapter(sql, conn) Chapter 3 -idbAdapter ADO.NET in Disconnected Environments Else in Connected Environments Chapter 4 Case - ADO.NET Function Chapter 5 -Exit Handling ADO.NET Events ChapterEnd 6 -Select Integrating XML with ADO.NET idbAdapter ChapterReturn 7 - Data Binding and Windows Forms Data-Bound Controls End Function Chapter 8 - Constraints and Data Relations End Class Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and returns Other .NET Data Providers TheGetDataAdapter method an IDbDataAdapter object created based on the connection Chapter 13 - Developing a Custom Data Provider and connection type variables passed in the method. You can also add methods to return a DataSet, a Chapter 14 - Developing Database DataReader, and other objectsWeb fromApplications this class. using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Now you're going to create a Windows that consumes the class in Listing 22-4. Add a Chapter 16 - ASP.NET Server Controls andapplication Data Binding GroupBox RadioButton controls, a DataGrid control, and a Button control. After Chapter 17 - control, Building four Real-World Web Applications changing properties of these controls, the final form looks like Figure 22-11. When you select a data Chapter 18 the - Object-Relational Mapping in .NET provider and click the Connect button, the program uses the selected data provider.


Figure 22-11: Generic data access class consumer application First, define some variables that you use in the application (see Listing 22-5). As you can see, this code defines connection strings for different data providers. Listing 22-5: User-Defined Variables ' User defined variables Private connString As String = Nothing Private sql As String = Nothing

Private conn As IDbConnection = Nothing AppliedAs ADO.NET: Building Data-Driven Solutions Private adapter IDbDataAdapter = Nothing ISBN:1590590732 by Mahesh Chand and David Talbot Private OleDbConnString As String = _ Apress © 2003 (928 pages) "Provider=Microsoft.Jet.OLEDB.4.0;" & _ This text provides extensive coverage of ADO.NET technology "Data Source=c:\\Northwind.mdb" including ADO.NET classes, and Private SqlConnString Asinternals, Stringnamespaces, = _ interfaces, and takes a comprehensive look at XML "Integrated Security=SSPI; Initial Catalog=Northwind;" & _ namespaces and classes, and how to integrate both with "Data Source=localhost;" ADO.NET. Private OdbcConnString As String Private OracleConnString As String Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter Second, 1 on - ADO.NET the Connect Basics button click event handler, you check what data provider is selected and based

on that 2selection, you create ainconnection using Chapter - Data Components Visual Studio .NETthe GetConnection method of the previously discussed class. You call the GetDataAdapter method that returns a DataAdapter. Chapter 3 -also ADO.NET in Disconnected Environments Chapter 4


Once data is in a DataAdapter, you simply call its Fill method to fill data from the DataAdapter to a - Handling ADO.NET Events DataSet. As you can see, the code opens a connection, creates and fills a DataSet, and then binds the Chapter 6 - Integrating XML with ADO.NET DataSet to the DataGrid. In this case, you have limited the functionality to Sql and OleDb data Chapter 7 - Data Binding and Windows Forms Data-Bound Controls providers, but you can also specify the connection strings for Oracle and ODBC data providers. Listing 22Chapter 8 how - Constraints Data data Relations 6 shows to use theand generic access class. Chapter 5

Chapter 9


Chapter Listing10 22-6: - Working Usingwith the the Generic ODBCData .NET Access Data Provider Class Chapter 11 - Stored Procedures and Views Chapter 12 -Sub Oracle, SQLXML, and Other .NET Data sender Providers As System.Object, _ Private ConnectBtn_Click(ByVal Chapter 13 -eDeveloping a Custom Data Provider ByVal As System.EventArgs) Handles ConnectBtn.Click Chapter'14 - DevelopingSQL Database Web Applications using ASP.NET Construct statement Chaptersql 15 -=Using ADO.NET Xml Web Services "SELECT * inFROM Employees" ChapterDim 16 -daComp ASP.NET Server As GenericDataAccessComp Controls and Data Binding = _ ChapterNew 17 -GenericDataAccessComp Building Real-World Web Applications

SQL data adapter Chapter'18 - Object-Relational Mapping in .NET Then ChapterIf 19 SqlRadioButton.Checked - Mapped Objects: Performance Considerations and Data Binding conn daComp.GetConnection(1, SqlConnString) Chapter 20 - COM= Interoperability and ADO.NET adapter = daComp.GetDataAdapter(1, conn, sql) Chapter 21 - Messaging ' OleDb data adapter ElseIf OleDbRadioButton.Checked Then Appendix A - Relational Databases: Some Basic Concepts conn = daComp.GetConnection(2, OleDbConnString) Appendix B - Commonly Used SQL Statements adapter = daComp.GetDataAdapter(2, conn, sql) Appendix C - ADO.NET Frequently Asked Questions End If Index ''' Add code for other data adapters Chapter 22 - SQL Server and ADO.NET: Notes on Performance

List of Figures List of Tables ' Open connection. If you don't open it explicitly, List of Listings ' calling DataAdapter will open it internally List of Sidebars If conn.State ConnectionState.Open Then

conn.Open() End If ' Create and fill a DataSet Dim ds As DataSet = New DataSet adapter.Fill(ds) ' Display DataSet in DataGrid DataGrid1.DataSource = ds.Tables(0) ' Close connection If conn.State = ConnectionState.Open Then conn.Open() End If

End Sub End Class


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Now if you run the application click the Connect button, interfaces, andand takes a comprehensive look atyou'll XML see data in the DataGrid. namespaces and classes, and how to integrate both with You can extend the functionality of this generic data access component by adding various methods and ADO.NET.

their overloaded forms. You can also add functionality for other data providers including Oracle, MySql, and WinCE. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Choosing a Development Mode: Designer vs. Manual

Introduction

Chapter 1 -covered ADO.NET Basics This book both designer and manual approaches for adding data components to applications. Chapter 2 - Data Components in to Visual .NETless time to write data-driven applications. (See Chapter 2 The designer approach is easy use Studio and takes Chapter 3 details.) - ADO.NET Disconnected Environments for more Youinsimply drag and drop data components to a form and follow simple steps using Chapter 4 and - ADO.NET in Connected Environments wizards, the application is ready in few minutes. For example, say you want to write a Windows Chapter application 5 - that Handling allows ADO.NET users toEvents view, delete, edit, update, and navigate data through DataGrid controls Chapter and you6 already - Integrating know the XMLdatabase with ADO.NET and database tables. In this scenario, using the Data Form Wizard

isn't a bad you have noForms idea what happened under the hood; further, this approach is rigid, Chapter 7 -idea. Data However, Binding and Windows Data-Bound Controls and there's flexibility.and YouData canRelations go and edit code by hand, but the queries written by the designer are a Chapter 8 - no Constraints big headache if you try to update them manually. On the other hand, if you write code manually, you know Chapter 9 - ADO.NET Exception Handling what code where and it works. Writing code manually may be time consuming, but it's worth it for Chapter 10 -isWorking with how the ODBC .NET Data Provider experienced developers who know how and where to write code. Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Alternatively, you can mix the approaches to get the best out of both worlds. You can use the designer to

Chapter 13 -controls, Developing Custom add some anda you can Data writeProvider some code manually. Chapter 14 - Developing Database Web Applications using ASP.NET

Again, it on you toindecide what approach to adapt. We prefer the manual approach over the Chapter 15depends - Using ADO.NET Xml Web Services designer the designer writes lots of unwanted code and leaves no option to modify it. Chapter 16approach - ASP.NETbecause Server Controls and Data Binding For beginners, it's better to useWeb a designer rather than writing bad code. (But if you're already on Chapter Chapter 17 - Building Real-World Applications 22 of this then you're not a beginner anymore! ) Chapter 18 book, - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Retrieving Data: DataReader, XmlReader, and DataSet


One of 22 themost frequently asked questions onPerformance discussion forums and newsgroups relates to whether you Chapter SQL Server and ADO.NET: Notes on

should use a DataReader or a DataSet. You can use a DataReader,XmlReader, and DataSet to retrieve data from a database. When reading hundreds of records, the DataReader is twice as fast as an Appendix B - Commonly Used SQL Statements XmlReader or DataSet. This difference gets bigger when there's higher user load and more records. Appendix A - Relational Databases: Some Basic Concepts Appendix C - ADO.NET Frequently Asked Questions

Index Now, the question is this: Which one do you use? Obviously, the XmlReader has no competition. The List of Figures is between the DataReader and the DataSet. You use a DataReader when you need to competition List of Tables simply read data in data types or streams-for example, when you need to display data on a system List console. of Listings You use a DataSet when you need to display data in data-bound controls and do something

more with the data such as editing and deleting data through a DataGrid control. List of Sidebars Note For more information, read "Building Distributed Applications with Microsoft .NET" at http://msdn.microsoft.com/library/default.asp?url=/library/enus/dnbda/html/bdadotnetarch13.asp.

Updating a Data Source: Command vs. DataSet You have two approaches for adding and updating data to a data source: using commands or using a DataSet. For example, if you want to use a command, you construct a SQL statement (INSERT, UPDATE, or DELETE) and execute the command using SqlCommand or another data provider's Command object. If you want to use a DataSet, you go through the DataSet and call the AddNew,Edit, or

Delete members of a DataTable to add, update, and delete (respectively). Both of the approaches Applied ADO.NET: Building Data-Driven have their uses. Executing commands give you control overSolutions the entire table, and using the DataSet ISBN:1590590732 by Mahesh Chand and David Talbot approach limits you to a record. For example, you can construct UPDATE and DELETE SQL statements Apress © 2003 (928 pages) and execute them using commands to update and delete all records of a table. On the other hand, a This text provides extensive coverage of ADO.NET DataTable provides a way to access all records in the form of atechnology collection, where you can loop through including ADO.NET internals, namespaces, classes, and these records one by one and do whatever you want to do with them. interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with So, again, which ADO.NET. one should you choose? It depends on your application requirements. If you're using a

DataGrid bound to a DataSet and want to delete a particular record, your obvious choice would be to use the DataTable.Rows.Delete method. But if there's no DataSet available in your application and Table you want of Contents to delete a record based on some criteria, you can simply construct a DELETE statement with a WHEREADO.NET—Building clause and execute it using the Command object. Applied Data-Driven Solutions Introduction

If you want to add a record to a database, executing a command is faster than a DataSet. This is also the - ADO.NET Basics case with delete and update operations.

Chapter 1 Chapter 2


Chapter 3


Saving- Data UsingEnvironments GetChanges ADO.NETand in Connected

Chapter 4 Chapter 5


When using a DataAdapter.Update method, it's a good idea to send only updated records back to the - Integrating XML with ADO.NET database. The GetChanges method of the DataSet returns the updated records. See FAQ 18 of Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Appendix C for more details. Chapter 6 Chapter 8


Chapter 9


Retrieving Data with the SELECT Statement


UsingSELECT * FROM TableName is a common statement to retrieve data from a database. It doesn't matter whether you read data through a DataReader or a DataSet. You don't even have to think about Chapter 13 - Developing a Custom Data Provider what columns a database table has. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


In most15 of -the cases, you don't need allServices the columns of a table. Don't use SELECT * unless you really Chapter Using ADO.NET in Xml Web need all Instead, use your column names. For example, if you want to select only the FirstName and Chapter 16data. - ASP.NET Server Controls and Data Binding LastName of the Employees table, use SELECT FirstName, LastName FROM Employees Chapter 17 -columns Building Real-World Web Applications instead18 of -SELECT * FROM Mapping Employees. Chapter Object-Relational in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Using Stored Procedures


Stored 22 procedures are and highly optimized objects and reduce network traffic, code size, execution time, and Chapter - SQL Server ADO.NET: Notes on Performance server overhead. Use Databases: store procedures instead of creating SQL commands if possible. Appendix A - Relational Some Basic Concepts Appendix B - Commonly Used SQL Statements

Using Connection Strings and Pooling


ADO.NET sends all Connection objects to a pool after a connection closes. When there's a need for a List of Figures connection, List of Tables instead of creating a new connection, you use a connection from the pool. But there's a

limitation in connection pooling: The connection string must be the same. This means, if possible, you should store a connection string as a program-level scope variable and use it instead of creating a List of Sidebars dynamic connection string each time you create a connection. List of Listings

Summary


ISBN:1590590732

Getting good performance out(928 of SQL Apress © 2003 pages)Server is not as hard as many people believe. It's largely a matter of knowing what tools are available to you and coverage knowing aoffew small technology tricks of the trade. In this chapter, you This text provides extensive ADO.NET saw some tricks related to SQL Server. You also learned about some including ADO.NET internals, namespaces, classes, and tricks and performance issues with interfaces, and takes a comprehensive look at XML different objects of ADO.NET. namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Building Data-Driven Solutions AppendixApplied A: ADO.NET: Relational Databases: Some Basic ISBN:1590590732 by Mahesh Chand and David Talbot ConceptsApress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET. This appendix discusses some key concepts of relational databases, including normalization, sets,

Overview

cursors, and locking. Table of Contents

Arelational database is a collection of tables, and a table is a set of columns and rows. A table's columns

Applied Data-Driven can beADO.NET—Building referred to as columns, fields, Solutions or attributes, and each column in a table requires a unique name Introduction and a data type. The datum in a given row is generally referred to as a record. (The term recordset refers Chapter ADO.NET Basics to a set1of -records, reminding you that relational databases use set-based operations rather than row-at-aChapter 2 - Data Components in Visual Studio .NET time, pointer-based operations.) Chapter 3

- ADO.NET in Disconnected Environments In relational databases, each tableEnvironments needs to have a key, which is associated with a column. There are two Chapter 4 - ADO.NET in Connected

important of keys: primary keys and foreign keys. A primary key is a column of a table with a unique Chapter 5 types - Handling ADO.NET Events value for each row, which helps ensure data integrity by (theoretically) eliminating duplicate records. A - Integrating XML with ADO.NET foreign key takes care of the relational in relational databases and provides a link between related data Chapter 7 - Data Binding and Windows Forms Data-Bound Controls that are contained in more than one table. For example, in a classic parent-child relationship such as Chapter 8 - Constraints and Data Relations customers and orders, if CustomerId is the primary key in the Customers table, it'll need to occur in the Chapter 9 - ADO.NET Exception Handling Orders table as a foreign key to associate each order with an individual customer. The customer/order Chapter 10 - Working with the ODBC .NET Data Provider relationship is a one-to-many relationship because each one customer can have many orders. That Chapter 11 - Stored Procedures and Views relationship is sometimes depicted as 1:n. Chapter 6


Note primary keya can alsoData be aProvider combination of several columns of a table, where one of those Chapter 13 A - Developing Custom is a Database foreign key. For example, using in an example Chapter 14 columns - Developing Web Applications ASP.NET database table, one table can have a key that'sina Xml combination of the Path and File columns to avoid duplicate file records. Chapter 15 primary - Using ADO.NET Web Services File column a foreign key. Chapter 16 The - ASP.NET ServerisControls and Data Binding Chapter 17 - Building Real-World Web Applications

Adatabase is a collection of tables, indexes, constraints, and other objects. The definition of these objects is known as the database's schema, which can be represented in a graphical way using various diagrams.



Chapter Meta-data 20 -refers COM Interoperability to the collectionand of ADO.NET data that describes the content, quality, relations, and other

characteristics of data. A database's meta-data includes information that ranges from table definitions to Chapter 21 - Messaging users and Chapter 22 -their SQLpermissions. Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

AppliedNormalization ADO.NET: Building Data-Driven Solutions Understanding by Mahesh Chand and David Talbot

ISBN:1590590732

If you've been working databases Apresswith © 2003 (928 pages)for a while, you're probably familiar with the term normalization. Database designers or developers often askcoverage whether of a database is normalized. So, what's normalization? This text provides extensive ADO.NET technology Normalization is aincluding processADO.NET of eliminating data redundancy (except for the redundancy required by foreign internals, namespaces, classes, and interfaces,tables, and takes look is atorganized XML keys) in multiple relational andaitcomprehensive ensures that data efficiently. When you normalize a namespaces classes, database, you basically have and three goals:and how to integrate both with ADO.NET.

Ensuring you've organized the data correctly into groups that minimize the amount of duplicate data stored in a database Table of Contents Applied ADO.NET—Building Data-Driven Solutions Organizing the data such that, when you (or your users) modify data in it (such as a person's address Introduction or email), the change only has to be made once Chapter 1

- ADO.NET Basics

Designing a database in which youStudio can access Chapter 2 - Data Components in Visual .NET and manipulate the data quickly and efficiently without compromising the integrity of the data in storage Chapter 3 - ADO.NET in Disconnected Environments Chapter 4


E. F. Codd first proposed the normalization process in 1972. Initially, he proposed three normal forms, - Handling ADO.NET Events which he called first,second, and third normal forms (1NF, 2NF, and 3NF). Subsequently, he proposed a Chapter 6 - Integrating XML with ADO.NET stronger definition of 3NF, known as Boyce-Codd Normal Form (BCNF). Later, others proposed fourth Chapter - Data Binding and normal Windows Forms Data-Bound Controls normal7form (4NF) and fifth form (5NF). Most people agree that a database that's in 3NF is Chapter 8 good - Constraints and Datawords, Relations probably enough-in other normalized enough. Chapter 5

Chapter 9



First Normal Form (1NF)

Chapter 11 - Stored Procedures and Views Chapter - Oracle, SQLXML, Other .NET Data Providers A table12 is in 1NF if the valuesand of its columns are atomic, containing no repeating values. Applying 1NF on a Chapter 13 - Developing a Custom Data Provider table eliminates duplicate columns from the same table, which creates separate tables for each group of Chapter - Developing ASP.NET related14 data, and adds Database a primaryWeb key Applications to the table using to identify table rows with a unique value. For example, Chapter - Using ADO.NET in Xml(see WebFigure Services say you15have a Customers table A-1). The Customers table stores data about customer Chapter orders.16 The - ASP.NET columnsServer store data Controls about and a Data customer Binding such as name, address, and order description. Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables

Figure A-1: Customers table before normalization

List of Listings

List of Sidebars

The data of the Customers table looks like Figure A-2.

Figure A-2: Two rows of data from the Customers table Figure A-1 shows the design of a Customers table. As you can see, it's been designed to store up to three orders for any customer-sort of mimicking an array structure in spreadsheet format. There are obvious problems with this design. As you can see from Figure A-2, there are many columns related to orders (that's a classic giveaway of a poorly designed table-mixing two or more entities, or kinds of data).

Whenever a customer posts a new order, a new column will be added to the table. Not only that, if the Applied ADO.NET: Building Data-Driven Solutions same customer posts more than one order, the duplicate Address and City column data will be added to ISBN:1590590732 by Mahesh Chand and David Talbot the table. This scenario adds duplicate data to the table. This table isn't in 1NF because the 1NF rule says Apress © 2003 (928 pages) that a table is in 1NF if and only if a table's columns have no repeating values. This text provides extensive coverage of ADO.NET technology ADO.NET internals, classes, and providing just enough relational You apply 1NF onincluding this table by eliminating thenamespaces, details about the orders, and takes a comprehensive look table. at XMLThe new format of this table after 1NF information to linkinterfaces, the Customers table with a new Orders namespaces and classes, and how to integrate both with looks like Figure ADO.NET. A-3. You still have some information about orders in this Customers table but only basic link information: OrderNumber. You've fixed the repeating fields problem by jamming all the other order information into a single OrderDescription field. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8 - A-3: Constraints and Data Figure Customers tableRelations schema after 1NF Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

The data of the table now looks like Figure A-4.


Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - A-4: Mapped Objects: Performancetable Considerations Figure Data of the Customers after 1NF and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

Second Normal Form (2NF)


2NF eliminates redundant A table is in 2NF if it's in 1NF and every nonkey column (not a key Appendix B - Commonly Useddata. SQL Statements column-primary or foreign) is fully dependent upon the primary key. Appendix C - ADO.NET Frequently Asked Questions Index

Applying 2NF on a table removes duplicate data on multiple rows, places data in separate rows, places grouped data in new tables, and creates relationships between the original tables and new tables through List of Tables foreign keys. As you can see from Figure A-4, there are six records for two customers and three columnsList of Listings CustomerName, Address, and City has the same information three times. 2NF eliminate these cases. List of UnderSidebars 2NF, you separate data into two different tables and relate these tables using a foreign key. Records in tables should not depend on anything other than the table's primary key. List of Figures

In this example, you now create a separate Orders table. As you can probably guess, the Orders table stores information related to customer orders. It relates back to the correct customer via the CustomerId column. Now the two tables, Customers and Orders, look like Figure A-5 and Figure A-6.


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Figure A-5: Customers table aftera 2NF interfaces, and takes comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Figure A-6: Orders table after 2NF

Chapter 6

- Integrating XML with ADO.NET As you 7can- Data see from Figures A-5 and Forms A-6, both tables now have a primary key-denoted by the key icon to Chapter Binding and Windows Data-Bound Controls

the left 8of the column name. ThisRelations key will be unique for each record. The CustomerId column of the Chapter - Constraints and Data Customers is mapped to the CustomerId column of the Orders table. The CustomerId column of the Chapter 9 - table ADO.NET Exception Handling Orders10 table is a foreign The relationship between the Customers and Orders tables looks like Figure Chapter - Working with key. the ODBC .NET Data Provider A-7.

Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Figure Relationship between the Customers and Orders tables Appendix B - A-7: Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Now the data in these tables look like Figure A-8 and Figure A-9.

Index

List of Figures List of Tables List of Listings List of Sidebars

Figure A-8: Customers table after 2NF

Figure A-9: Orders table after 2NF


ISBN:1590590732

Third Normal Form (3NF) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

A table is in 3NF interfaces, if all columns of a table depend upon the primary key. 3NF eliminates columns that don't and takes a comprehensive look at XML depend on the table's primaryand key. (Note that primary keys don't have namespaces classes, and how to integrate both withto be single columns as shown in these simple examples.) ADO.NET. For example, as you can see from Figure A-10, CustomerId, UnitPrice, and Quantity depend on OrderId Table Contents (the of primary key). But the Total column doesn't depend on the OrderId column; it depends upon the Applied ADO.NET—Building Data-Driven UnitPrice and the Quantity columns. Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7 - A-10: Data Binding Windows Forms Data-Bound Controls Figure Ordersand table after 3NF Chapter 8 - Constraints and Data Relations

The data the Orders table look like Figure A-11 after applying the 3NF rule on it, and you can calculate Chapter 9 of - ADO.NET Exception Handling Total as multiplication of ODBC UnitPrice Quantity in your SQL statement. Chapter 10the - Working with the .NETand Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - A-11: Building Real-World Web Applications Figure Data of the Orders table after 3NF Chapter 18 - Object-Relational Mapping in .NET

For example: Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 UnitPrice - Messaging * Quantity AS Total FROM Orders SELECT Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Boyce-Codd Normal Form (BCNF)


List Adeterminant of Figures column is the column on which other columns are fully dependent. BCNF is an extended

version of 3NF. A database is in BCNF if and only if every determinant is a candidate key. A candidate key List of Tables is aofcombination of columns that can be uniquely used to identify a row. Each table may have one or more List Listings candidate keys. List of Sidebars

Fourth Normal Form (4NF) 4NF and 5NF seem to be of interest only in computer science classes and in the academic world in general. But, if you're really interested, a database is in 4NF if and only if it's in BCNF and all multivalued dependencies are also functional dependencies. For example, a customer can have multiple orders and multiple addresses. This data (the customer having multiple addresses and multiple orders) can be stored in a single table, but after applying 4NF, the data will be stored in two tables. The first table stores the CustomerId with addresses, and the second table stores the CustomerId with orders.

Fifth Normal Form (5NF or PJ/NF)

A database is in 5NF-or Normal Form (PJ/NF)-if it can't have a lossless decomposition into AppliedProjection/Join ADO.NET: Building Data-Driven Solutions any number of smaller tables. In other words, this means a table that has been decomposed into three or ISBN:1590590732 by Mahesh Chand and David Talbot more smaller tables must be capable of being joined again on common keys to form the original table. Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology Note This ends the quick overview of normal forms. SQL Server Magazine has numerous articles including ADO.NET internals, namespaces, classes, and about database and anormal forms that youatmight interfaces,design and takes comprehensive look XML find helpful at www.sqlmag.com/Articles/Index.cfm?AuthorID=436. namespaces and classes, and how to integrate both with ADO.NET.

Note If you've heard about database normal forms and normalization, chances are you've also heard aboutdenormalization, which basically refers to the process of embracing a less than rigorously Table of Contents perfect relational design in favor of performance. You might, for example, include calculated Applied ADO.NET—Building Data-Driven Solutions fields or aggregations in your design. By including redundant information in your design, you Introductiondenormalize it. Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Building Data-Driven Solutions IntroducingApplied Sets,ADO.NET: Cursors, and ADO.NET by Mahesh Chand and David Talbot

ISBN:1590590732

Cursors were basically to SQL Apressadded © 2003 (928 pages)to accommodate programmers who preferred row-at-a-time, pointer-style processing. Real relational databases don't even have a notion of record number, for This text provides extensive coverage of ADO.NET technology example; you useincluding a SELECT statement to obtain record sets. ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces andredesigned classes, andfrom howscratch. to integrate both no with The ADO.NET model has been There's explicit support for cursors in ADO.NET. ADO.NET. Why do you need cursors? This is a good question. To get your answer, first you have to find out what cursors do. Table of Contents

In ADO, a recordset represents the set of rows returned from a data source after executing a SQL

Applied ADO.NET—Building Data-Driven statement. A recordset uses a cursorSolutions to keep track of the current location and navigate through rows. Introduction

ADO supports four types of cursors: static, forward-only, keyset, and dynamic. The static cursors are a Chapter 1 - ADO.NET Basics static copy records on the client side. Static.NET cursors are either read-only or read/write and provide both Chapter 2 - of Data Components in Visual Studio backward forward by Environments using the MoveFirst,MoveNext,MovePrevious,MoveLast, and Chapter 3 -and ADO.NET in navigation Disconnected Move methods of theinrecordset. Also, you can bookmark records using this type of cursor. The Chapter 4 - ADO.NET Connected Environments AbsolutePosition property provides the row number of a cursor. - Handling ADO.NET Events

Chapter 5 Chapter 6

- Integrating XML with ADO.NET Forward-only cursors are similar to static cursors except they support forward-only navigation from the first

Chapter 7 -record Data Binding and Windows Forms Data-Bound to the last in the cursor. You can update records, Controls insert new records, and delete records, but you Chapter 8 - backward. Constraints The and forward-only Data Relationscursor supports only the MoveNext method of the recordset. can't move Chapter 9

- ADO.NET Exception Handling Keyset 10 cursors support backward navigation through the recordset object's Move Chapter - Working withboth the ODBC .NETand Dataforward Provider

methods. addition to that, they reflect changes made by other users. Dynamic cursors provide Chapter 11 In - Stored Procedures andalso Views dynamic and reflect changes Chapter 12navigation - Oracle, SQLXML, andall Other .NET immediately. Data ProvidersThey're useful when your application allows multiple13users to add, update, delete, and navigate records simultaneously. Dynamic cursors are flexible, Chapter - Developing a Custom Data Provider but they don't support absolute positioning and bookmarks.

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15when - Using Xml Web you Services In ADO, youADO.NET create ainrecordset, can specify the type of cursors to use. Table A-1 represents the Chapter 16 ASP.NET Server Controls and Data Binding cursor types and their values. Chapter 17 - Building Real-World Web Applications Chapter 18 - Recordset Object-Relational Mapping .NET Table A-1: Cursor Type in and Their Values in ADO Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

CONSTANT

VALUE

DESCRIPTION

0

Forward-only recordset cursor (the default)

Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging adOpenForwardOnly


adOpenKeyset 1 Some Basic Keyset recordset cursor Appendix A - Relational Databases: Concepts Appendix B - Commonly Used SQL AdOpenDynamic 2 Statements Dynamic recordset cursor Appendix C - ADO.NET Frequently Asked Questions

AdOpenStatic

Index

3

Static recordset cursor

List of Figures

As you can see, ADO uses cursors to navigate, to position, and to bookmark records in a recordset. ADO.NET represents a new approach. To be blunt, recordsets are history! The DataTable and List of Listings DataReader have replaced them. Under ADO.NET, a DataReader enables you to perform the function List of Sidebars of the forward-only, server-side cursor. However, a DataReader doesn't have a MoveNext method, which moves to the next record of a recordset. But it provides a Read method, which reads all the records until the end of the records. A DataReader is useful when you need to read data fast with no updates and you're not using data-bound controls. List of Tables

TheDataSet and Command objects enable you to work with data as a disconnected source, which is similar to ADO client-side behavior. This method is useful when you need to write data-bound, controlbased applications. ADO.NET doesn't support server-side cursors. However, you can use server-side cursors through ADO by adding a reference to the ADODB type library by generating a .NET wrapper for its objects.

Applied ADO.NET: Building Data-Driven Solutions Using Locking by Mahesh Chand and David Talbot

ISBN:1590590732

In database terms, locking is a(928 mechanism used to avoid inconsistency when multiple users access and Apress © 2003 pages) update data simultaneously. Using the locking technique, you cantechnology lock records or a database table when a This text provides extensive coverage of ADO.NET user is modifying including the records or table, and the data will be unavailable ADO.NET internals, namespaces, classes, and for other users until the current user interfaces, and takes comprehensive look at XML calls the update method to make finalachanges. For example, say user A is updating a record. During this classes, how tomay integrate both with operation, user Bnamespaces deletes thatand record. Thisand scenario lead to inconsistency in the table. You can avoid ADO.NET. this inconsistency by making that record unavailable when user A is updating it and make it available when user A is done updating it. The only drawback of this is user B has to wait until user A is done updating the record. Oh well, waiting is better than having inconsistencies and inaccurate data. Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Isolation Levels


- ADO.NET Basics

Anisolation represents ainparticular locking strategy applied on a database. It's basically a way of Chapter 2 - level Data Components Visual Studio .NET representing the stages of locking depending on Chapter 3 - ADO.NET in Disconnected Environmentsthe complexity of locking. There are four isolation levels, starting4from level 0 to ApplyingEnvironments these levels on transactions is also called determining Transaction Chapter - ADO.NET in 3. Connected Isolation Levels (TILs). Chapter 5 - Handling ADO.NET Events Chapter 6

- Integrating XML with ADO.NET TILs provide consistency during data manipulation when multiple users are accessing data

Chapter 7 - Data There Binding and Windows Data-Bound Controls simultaneously. are three casesForms that apply to the transactions: Chapter 8


Chapter 9 read: - ADO.NET Exception Handling Dirty A dirty read occurs when a user reads data that have not yet been committed. For Chapter 10 Working with the ODBC .NET Data Provider example, user 1 changes a row. User 2 reads the row before user 1 commits the changes. What if Chapter 11 Stored Procedures and Views user 1 rolls back the changes? User 2 will have data that never existed. Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

Nonrepeatable read: A nonrepeatable read occurs when a user reads the same record twice but gets different data each time. The simple case for this situation is when user 1 reads a record. User 2 Chapter 15 - Using ADO.NET in Xml Web Services goes and either changes a record or deletes a record and commits the changes. Now if user 1 tries to Chapter 16 the - ASP.NET Server Controls and1Data read same records again, user getsBinding different data. Chapter 14 - Developing Database Web Applications using ASP.NET


Phantom: A phantom is a record that matches the search criteria but isn't initially seen. For example, say user 1 searches for records and gets some records. Now user 2 adds new rows with user 1's Chapter 20 - COM Interoperability and ADO.NET search criteria. Now if user 1 searches again using the same criteria, user 1 gets different results than Chapter 21 - Messaging the previous one. Chapter 19 - Mapped Objects: Performance Considerations and Data Binding


Appendix A -describes Relationalthe Databases: Concepts Table A-2 isolationSome levelsBasic defined by OLE DB. Appendix B - Commonly Used SQL Statements Appendix C - Isolation ADO.NET Frequently Table A-2: Levels Asked Questions Index

LEVEL

List of Figures ListRead of Tables ListUncommitted of Listings List of Sidebars

DEFINITION A user can read uncommitted changes made by other users. At this level all three cases (dirty reads, nonrepeatable reads, and phantoms) are possible.

Read Committed

A user can't see changes made by other users until the changes are committed. At this level of isolation, dirty reads aren't possible, but nonrepeatable reads and phantoms are possible.

Repeatable Read

A user can't see the changes made by other users. At this level of isolation, dirty reads and nonrepeatable reads aren't possible, but phantoms are possible.

Serializable

A user sees only changes that are finalized and committed to the database. At this isolation level, dirty reads, nonrepeatable reads, and phantoms aren't possible.

Applied ADO.NET: Building Data-Driven Solutions Control and Recovery in Database Note The definitive book on transaction processing is Concurrency ISBN:1590590732 byby Mahesh and David TalbotHadzilacos, and Systems Philip Chand A. Bernstein, Vassos Nathan Goodman (Addison-Wesley, Apress 2003 (928 pages) 1987).You can© download it in its entirety as a 22.9MB self-extracting ZIP file from http://research.microsoft.com/pubs/ccontrol/. can also find related information at This text provides extensive coverage ofYou ADO.NET technology including ADO.NET internals, namespaces, classes, and http://research.microsoft.com/~philbe/. interfaces, and takes a comprehensive look at XML

namespaces andconsistency classes, andbehaviors how to integrate both with Table A-3 summarizes the data and isolation level relationship. (Read Committed is ADO.NET. SQL Server's default isolation level.)

Table Isolation Levels and Data Consistency Table of A-3: Contents Applied ADO.NET—Building Data-Driven Solutions

LEVEL

DIRTY READ?

NONREPEATABLE READ?

PHANTOM?

Yes

Yes

Yes

Yes

Yes

Repeatable Read (2) NoEnvironments Chapter 4 - ADO.NET in Connected

No

Yes

Chapter 5


Chapter 6


No

No

Chapter 7


Chapter 8


Introduction

Read 1Uncommitted (0) Chapter - ADO.NET Basics Chapter 2


Chapter 3


Read Committed (1)

Serializable (3)

No

No

Locking Modes - ADO.NET Exception Handling

Chapter 9


In general, locking avoids the consequences of multiple users accessing the same data simultaneously

Chapter 11to- Stored Procedures Views and tries maintain the data'sand consistency and integrity. There are two locking modes: shared and Chapter 12 Oracle, SQLXML, and Other .NET Dataaccess Providers exclusive. The shared mode lets multiple users the same data simultaneously. However, an

Chapter 13 mode - Developing a Custom Data Provider exclusive won't let user 2 access the data until user 1 unlocks the data. Depending on the database, Chapter - Developing Database Applications using ASP.NET you can14implement locking on a Web record, a table, or a page level. In table locking, a user can lock the entire Chapter 15 -he Using ADO.NET in Xml Web table until commits the changes andServices unlocks the table. The same method applies on a page as well as Chapter on a record 16 - ASP.NET for page-level Serverand Controls record-level and Datalocking. Binding Chapter 17 - Building Real-World Web Applications

Note Chapters 4 and 5 discuss ADO.NET concurrency.


Chapter - Mapped Objects: Performance Considerations anddifferent Data Binding Based 19 on these general locking modes, ADO provides two types of locking on recordsets and the Chapter 20 COM Interoperability and ADO.NET combination of them: optimistic locking and pessimistic locking. Optimistic locking is based on the Chapter 21 - Messaging assumption that there won't be any other users when a user is accessing some records of a table. Chapter 22 - SQL Server and ADO.NET: Notes on Performance

In optimistic locking, locking only Some occursBasic during the final update of records. If any changes were made to Appendix A - Relational Databases: Concepts the dataBsince it was last accessed, the application must read data again and update the data. Appendix - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

In pessimistic locking, records are unavailable to other users when a user is accessing records until the user makes the final changes.

Index

List of Figures

List You of can Tables pass an argument when you create a recordset to specify the type of locking. Table A-4

describes these values. List of Listings List of Sidebars

Table A-4: Locking Types CONSTANT

VALUE

DESCRIPTION

adLockReadOnly

1

Read-only

adLockPessimistic

2

Pessimistic locking

adLockOptimistic

3

Optimistic locking

adLockBatchOptimistic

4

Optimistic locking with batch updates

You set the LockType variable in the recordset to 1 when you need to read data. It doesn't allow you to

add or update data.


You use LockType=3, by Mahesh or optimistic Chand and locking, David Talbot when you need toISBN:1590590732 lock records and only when ADO physically Apress © 2003 (928 pages) are available when you're editing them. In contrast to the optimistic updates the record. Otherwise, records locking, pessimistic locking locks the recordscoverage when you editing records. You set LockType=2 in that This text provides extensive of start ADO.NET technology including ADO.NET internals, anddatabase manufacturer supports it. case. Before applying optimistic locking, you namespaces, need to makeclasses, sure that interfaces, and takes a comprehensive at XML Some database manufacturers don't support optimisticlook locking. namespaces and classes, and how to integrate both with ADO.NET.

Optimistic locking with batch updates, LockType=4, enables you to access multiple records, update them locally, and update the database as a single batch operation. Again, before using this type of locking, you needoftoContents make sure the database manufacturer supports this type of locking. Many don't. Table Applied ADO.NET—Building Data-Driven Solutions

Note For more information on locking and concurrency levels, you may want to read Jim Gray's article on isolation levels at http://research.microsoft.com/~gray/Isolation.doc or Transaction Chapter 1 - ADO.NET Basics Processing: Concepts and Techniques by Jim Gray and Andreas Reuter (Morgan Kaufmann, Chapter 2 1993). - Data Components in Visual Studio .NET Introduction

Chapter 3


Chapter 4

- ADO.NET in Connected Environments What Are Deadlocks? - Handling ADO.NET Events

Chapter 5

If you've heard about concurrency and different kinds of locks, you've probably also heard about Chapter 6 - Integrating XML with ADO.NET deadlocks. they're Forms an inevitable fact ofControls life in the database world. But, fortunately, Chapter 7 - DataUnfortunately, Binding and Windows Data-Bound

today's- Constraints Database Management Systems (DBMSs) are typically designed to handle deadlocks-usually and Data Relations by selecting a "victim" whose transaction gets rolled back (or undone).

Chapter 8 Chapter 9


Chapter 10 -users Working with the ODBC .NET Data Provider When share access to database tables, they may prevent each other from completing Chapter 11 Stored Procedures and Views transactions. That's because a user who locks a table or a single record during an update may Chapter 12 - Oracle, SQLXML, andfrom Other .NET Data prevent other transactions acquiring theProviders locks they need to complete their task. As a result, the Chapter 13 transactions - Developing enter a Custom Data Provider other a wait state, waiting their turn. Sometimes, the locks are unresolvable, though. Chapter For14 example, - Developing if transaction DatabaseAWeb can't Applications complete until usingit ASP.NET acquires a lock being used by transaction B, and

transaction B ADO.NET can't complete acquires a lock being used by transaction A, the transactions enter Chapter 15 - Using in Xml until Web itServices a deadlock stateServer and neither canand complete unless the other is terminated. Chapter 16 - ASP.NET Controls Data Binding Chapter 17 - Building Real-World Web Applications

Microsoft describes deadlocks by noting the following: "A deadlock occurs when there is a cyclic dependency between two or more threads for some set of resources." It adds that deadlocks can Chapter 19 - Mapped Objects: Performance Considerations and Data Binding occur on any system with multiple threads, not just on a relational DBMS. Chapter 18 - Object-Relational Mapping in .NET



Summary


ISBN:1590590732

In this appendix, we discussed some of the basic concepts of relational databases. To learn more, you can Apress © 2003 (928 pages) access the following resources online: This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

"Database Normalization Basics": interfaces, and takes a comprehensive look at XML


http://support.microsoft.com/default.aspx?scid=KB;en-us;q209534 ADO.NET. "Database Normalization Tips" by Luke Chung: Table of Contents

http://msdn.microsoft.com/library/default.asp?url=/library/enApplied ADO.NET—Building Data-Driven Solutions us/dnacc2k2/html/odc_FMSNormalization.asp Introduction Chapter 1

- ADO.NET Basics

Chapter 2


"Database Normalization and Design Techniques" by Barry Wise:

Chapter www.devarticles.com/art/1/321 3 - ADO.NET in Disconnected Environments Chapter 4

- ADO.NET in Connected Environments Concurrency Control and Events Recovery in Database Systems by Philip A. Bernstein, Vassos Hadzilacos, Chapter 5 - Handling ADO.NET

and Nathan Goodman: - Integrating XML with ADO.NET

Chapter 6

Chapter 7 - Data Binding and Windows Forms Data-Bound Controls http://research.microsoft.com/pubs/ccontrol/ Chapter 8

- Constraints and Data Relations "Denormalization Guidelines" by Craig S. Mullins: Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

www.tdan.com/i001fe02.htm

Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, and Other .NET Data Providers "Getting Down SQLXML, to Data Basics" by Craig S. Mullins: Chapter 13 - Developing a Custom Data Provider

www.dbazine.com/edba4.html Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

"Transaction Isolation Levels" by Kalen Delaney:


Chapter 17 - Building Real-World Web Applications www.sqlmag.com/Articles/Index.cfm?ArticleID=5336 Chapter 18 - Object-Relational Mapping in .NET

"Responsible by Michelle A. Poolet: Chapter 19 - MappedDenormalization" Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

www.sqlmag.com/Articles/Index.cfm?ArticleID=9785


Chapter 22 - SQL Server and ADO.NET: Notes on Performance SQLCourse: www.sqlcourse.com Appendix A - Relational Databases: Some Basic Concepts

FreeB online versionUsed of Teach Yourself SQL in 21 Days, Second Edition: Appendix - Commonly SQL Statements Appendix C - ADO.NET Frequently Asked Questions

www8.silversand.net/techdoc/teachsql/index.htm

Index List ofFree Figures PowerPoint tutorial on Transact-SQL by Michael R. Hotek: List of Tables

www.mssqlserver.com/tsql/

List of Listings

List of Sidebars

Building Data-Driven Solutions AppendixApplied B: ADO.NET: Commonly Used SQL Statements ISBN:1590590732 by Mahesh Chand and David Talbot © 2003 (928 pages) Structured query Apress language (SQL) is a language you use to work with relational databases. In this appendix, This text provides coverage ADO.NET we'll discuss some commonly usedextensive SQL queries and of show how totechnology construct them. To test the SQL including ADO.NET internals, namespaces, classes, and statements, we'll use the familiar Northwind database-specifically, its Customers and Orders tables.

interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Note SQL queries are also referred to as SQL statements. ADO.NET.

Understanding SQL References

Table of Contents

Applied Data-Driven Solutions For theADO.NET—Building most part, we used Access 2000's Northwind database to illustrate the SQL statements discussed in Introduction this appendix, but you can also use the Northwind database that's in SQL Server. (We use the SQL Server Chapter - ADO.NET Basics version1in the examples in the "Understanding Views" section because Access doesn't support the SQL Chapter concept 2 of- views Data Components as virtual tables.) in Visual To Studio test SQL .NET statements, you can open the Northwind database in Access

and create new query by selecting Environments Queries and clicking the New button. This opens the New Query dialog Chapter 3 - aADO.NET in Disconnected box, as4shown in Figure B-1. Chapter - ADO.NET in Connected Environments Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure B-1: Creating a new query in Access 2000


Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 -Table COM Interoperability and ADO.NET The Show dialog box displays all the tables in the database and lets you pick the tables with which you Chapter want to21 work - Messaging (see Figure B-2). Click the Close button. Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure B-2: Selecting database tables

Now, you can open the Query Editor by simply right-clicking the query pane and selecting the SQL View menu Applied ADO.NET: Building Data-Driven Solutions item. The Query Editor is basically a blank screen that appears when you're creating a new query, but you can ISBN:1590590732 by Mahesh Chand and David Talbot also use it to examine the contents of existing queries (see Figure B-3). In this case, you can either type in a Apress © 2003 (928 pages) SQL statement directly or paste one in and then choose Query Ø Run Query to execute the statement. This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4

- ADO.NET in Connected Environments Figure TheADO.NET Query Editor of Access 2000 Chapter 5 - B-3: Handling Events Chapter 6


Chapter 7 take - Data Binding andNorthwind Windows Forms Data-Bound Controls Now let's a look at the database's Customers table. Figure B-4 shows the table schema (the Chapter 8 with - Constraints and Data Relations structure) its column names and their data types (all of type Text in this case). Note that the CustomerID Chapter 9 -primary ADO.NET Exception field is the key field. Handling Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index

Figure B-4: Customers table schema of the Northwind database


List of Orders Listingstable columns and their data types look like Figure B-5. OrderID is the primary key in the Orders The List table. of Sidebars CustomerID and EmployeeID function as foreign keys and provide the "glue" that links data in the

Customers table to data stored in Orders and Employees. (Employees is another table in the Northwind database that stores employee records.)


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Figure B-5: Orders table schema of the Northwind database

Using the SELECT Statement - ADO.NET Exception Handling

Chapter 9

Chapter 10 - Working withisthe .NET Data Provider TheSELECT statement theODBC workhorse of the SQL language; it enables you to retrieve data from database Chapter 11 Stored Procedures and Views tables and views. If you want to retrieve data from selected columns, you list the column names in the SELECT Chapter 12 - You Oracle, andclause Other .NET Data Providers statement. useSQLXML, the WHERE to retrieve data from selected rows. Chapter 13 - Developing a Custom Data Provider

The simplest form of the SELECT statement is SELECT...FROM, which returns records from a table defined Chapter 14 - Developing Database Web Applications using ASP.NET after FROM. the syntax: Chapter 15 - This UsingisADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

SELECT column2, FROM table Chapter 17 column1, - Building Real-World Web.., Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

For example, the following SELECT statement returns all records from the CustomerID, CompanyName, Address, and City columns of the Customers table:



SELECT CustomerID, CompanyName, Address, City FROM Customers


Appendix C - ADO.NET Frequently Asked Questions Index The output looks like Figure B-6. List of Figures List of Tables List of Listings List of Sidebars

Figure B-6: Output of the SELECT statement Note You can switch back to the SQL view be selecting View Ø SQL View.

You use SELECTApplied * to return ADO.NET: all columns Building fromData-Driven a table (the asterisk Solutions is a handy wildcard character in most dialects of SQL). by ForMahesh example, Chand theand following David statement Talbot returnsISBN:1590590732 all records from the Customers table: Apress © 2003 (928 pages) text provides extensive coverage of ADO.NET technology SELECT * FROMThis Customers including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with The output looks ADO.NET. like Figure B-7.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


Figure B-7: Output of SELECT * FROM Customers statement


There are occasions when database table stores redundant records, but you generally don't want Chapter 11 -some Stored Procedures and the Views duplicate use theData SELECT DISTINCT statement for this purpose. This is the Chapter 12 records - Oracle,returned. SQLXML, You and can Other .NET Providers syntax: 13 - Developing a Custom Data Provider Chapter Chapter 14 - Developing Database Web Applications using ASP.NET

SELECT column1, column2, Chapter 15 DISTINCT - Using ADO.NET in Xml Web Services .., FROM table Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

For example, the following statement returns only unique records from the Customers table:



SELECT DISTINCT CompanyName FROM Customers


Chapter 22 -to SQL Server and ADO.NET: Notes on Performance In addition restricting columns to those you're interested in, you can also restrict rows by using the Appendix A Relational Databases: Some Basic Concepts SELECT...FROM ...WHERE statement. The WHERE clause takes a conditional statement: Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

SELECT column1, column2, .., FROM table WHERE condition

Index List of Figures List Forofexample, Tables the following query: List of Listings List of Sidebars SELECT * FROM Customers WHERE CustomerID = "BOTTM"

returns records only having a CustomerID that equals BOTTM. The output of the Northwind database's Customers table looks like Figure B-8.


ISBN:1590590732



Figure B-8: Output of the SELECT...WHERE statement


- ADO.NET Basics

Chapter 2 -summarizes Data Components in Visual Studio .NET used in SQL. Table B-1 the conditional statements Chapter 3 - ADO.NET in Disconnected Environments Chapter Table B-1: 4 - Conditional ADO.NET in Connected Statements Environments Used in SQL Chapter 5


Chapter 6


Chapter 7


=

MEANING

Greater Than Not Equal To Equal To


You can also use the SUM and AVG functions to return the sum and average of numeric columns, respectively:


SELECT function(column) FROM table

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET For example, the following query returns the sum of the Freight column in the Orders table: Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 SUM(Freight) - COM Interoperability and ADO.NET SELECT FROM Orders Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

SeeFigure for theDatabases: output of this statement. Appendix A -B-9 Relational Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Figure B-9: Output of query that uses the SQL SUM function The following query returns the average of the Freight column: SELECT AVG (Freight) FROM Orders


You can use SELECT COUNT to return the number of rows in aISBN:1590590732 table (based on a column). This is the syntax: by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

SELECT COUNT(column) FROMextensive table coverage of ADO.NET technology This text provides including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML and classes, and the hownumber to integrate bothinwith For example, thenamespaces following statement returns of rows the Customers table: ADO.NET.

SELECT COUNT(CustomerID) FROM Customers; Table of Contents Applied ADO.NET—Building Data-Driven Solutions

The output of this statement looks like Figure B-10. Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure Output of COUNT Chapter 13 - B-10: Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

GROUP BY is another handy clause that returns results grouped by the mentioned column. This is the syntax:


SELECT column1, SUM(column2) FROM table GROUP BY column1


Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM and ADO.NET For example, theInteroperability following statement returns the number of rows grouped by OrderDate from the Orders Chapter table: 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix - Relational Databases: Some Basic Concepts SELECTA OrderDate, SUM(Freight) FROM Orders GROUP BY(OrderDate) Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

The output of the query looks like Figure B-11. Index List of Figures List of Tables List of Listings List of Sidebars

Figure B-11: Output of GROUP BY

TheHAVING clause limits output based on a criterion. You can use it with or without the GROUP BY clause. This is the syntax:Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

SELECT column1, column2 FROM table GROUP BY column1 HAVING condition

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML For example, thenamespaces following statement returns of the OrderDate and classes, and records how to integrate both with column that have a total freight of more than 900: ADO.NET.

SELECT OrderDate FROM Orders GROUP BY(OrderDate) HAVING SUM(Freight) > 900

Table of Contents


Using the UPDATE Statement - ADO.NET Basics

Chapter 1 Chapter 2


TheUPDATE statement makes changes to existing records in a database table. The UPDATE statement takes - ADO.NET in Disconnected Environments database table names and table columns and their values.

Chapter 3 Chapter 4


Chapter 5 - for Handling ADO.NET Events The syntax UPDATE statement is as follows: Chapter 6 - Integrating XML with ADO.NET Chapter 7

- Data Binding and Windows Forms Data-Bound Controls UPDATE table SET column1 = [new value], column2 =[new value],.,WHERE {condition}

Chapter 8


Chapter 9


Chapter For example, 10 - Working the following with thequery ODBCupdates .NET Data theProvider Freight column value to 500 in the Orders table where OrderId is

10248:11 - Stored Procedures and Views Chapter Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 Orders - Developing Data UPDATE SETa Custom Freight = Provider 500 WHERE OrderId = 10248 Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Using a16comma, youServer can update as and many as Binding columns as you want. If you want to update all the rows of a Chapter - ASP.NET Controls Data

column or more than one column, you don't use the WHERE clause. For example, the following query updates all the rows of the Freight column with the value of 500:



UPDATE SET Freight 500 Chapter 20 Orders - COM Interoperability and = ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Using the DELETE Statement


TheDELETE statement removes records from a database table. Using the DELETE statement, which is dangerously simple, you can either delete records based on certain criteria or delete all the records of a Index database table. Appendix C - ADO.NET Frequently Asked Questions List of Figures

List of syntax Tables of the DELETE statement is as follows: The List of Listings List of Sidebars

DELETE FROM table WHERE {condition}

For example, the following statement deletes all rows of OrderId 10248 (there should be only one because OrderID is the primary key): DELETE FROM Orders WHERE OrderID = 10248

If you want to delete all of a table's rows, retaining an empty table, you can use the following statement:

DELETE FROM Orders Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

(In Access, DELETE Apress statements © 2003 (928 can pages) impact more than one table's rows depending on whether cascading deletes are enabled.) This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Using the CREATE TABLE Statement

A database table is a collection of rows and columns. Each field in a table is represented as a column. Each field of a table must have a defined data type and a unique name. You can use the CREATE TABLE statement Table of Contents to create database tables programmatically. Applied ADO.NET—Building Data-Driven Solutions

The syntax for CREATE TABLE is as follows: Introduction Chapter 1

- ADO.NET Basics

Chapter 2 TABLE - Data Components in Visual Studio .NET CREATE table (column1 column1_datatype, Chapter column2 3 -column2_datetype, ADO.NET in Disconnected.., Environments column column_datatype) Chapter 4


Chapter 5


The following statement creates a myTable table with the columns myId, myName, myAddress, and - Integrating XML with ADO.NET myBalance, which can store integer, character 50, character 255, and floating values, respectively. The Chapter 7 - Data Binding and Windows Forms Data-Bound Controls CONSTRAINT...PRIMARY KEY syntax makes a column a primary key column: Chapter 6 Chapter 8


Chapter 9


CREATE TABLE myTable (myId INTEGER CONSTRAINT PKeyMyId PRIMARY KEY, myName CHAR(50), myAddress CHAR(255), myBalance FLOAT)



Using the DROP TABLE Statement


There might be some occasions when either you need to delete a table permanently or you need to create temporary, "scratch" tables and then delete them. The DROP TABLE statement deletes a database table.

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - for Object-Relational in .NET The syntax DROP TABLEMapping is as follows:

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COMtable Interoperability and ADO.NET DROP TABLE Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

For example, the following deletes myTable from the database: Appendix B - Commonly Usedstatement SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index DROP TABLE myTable List of Figures List of Tables

Using the TRUNCATE TABLE Statement

List of Listings

List of Sidebars

DROP TABLE deletes all records of a table and the table itself from the database. But what if you don't want to delete the table, just its records? One way of doing this is to use the DELETE FROM query. TRUNCATE TABLE is another way to remove the data of a table without getting rid of the table itself. TRUNCATE TABLE removes all records from a table without logging the individual record deletes. The DELETE statement removes records one at a time and makes an entry in the transaction log for each deleted record. TRUNCATE TABLE is faster than DELETE because it removes the data by deallocating the database table data pages, and only deallocations of the pages are recorded in the transaction log. TRUNCATE TABLE doesn't remove the table structure, columns, constraints, or indexes. If you want to remove a table definition and its data, use DROP TABLE instead. The syntax of this statement is simple:

Applied ADO.NET: Building Data-Driven Solutions TRUNCATE TABLE table by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

For example, theThis following statement truncates the Customers table: text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML TRUNCATE TABLE Customers namespaces and classes, and how to integrate both with ADO.NET.

Table Note of Contents Access databases don't natively support TRUNCATE TABLE. Applied ADO.NET—Building Data-Driven Solutions Introduction

Using the INSERT Statement - ADO.NET Basics

Chapter 1

Chapter 2 - Data Components in Visual Studio .NETinformation from tables. But how do these rows of data get In the previous sections you saw how to retrieve Chapter - ADO.NET in Disconnected into the3tables in the first place? This Environments is what this section, covering INSERT INTO, and the next section, Chapter covering 4 UPDATE, - ADO.NET areinabout. Connected Environments Chapter 5

- Handling ADO.NET Events There are twoXML ways to insert data into a table. One way is to insert them one row at a time, and the Chapter 6 -basically Integrating with ADO.NET

other way -isData to insert the data several rows at a time. First let's look at how you can insert data one row at a Binding and Windows Forms Data-Bound Controls time.

Chapter 7 Chapter 8


Chapter 9 - for ADO.NET Exception Handling The syntax inserting data into a table one row at a time is as follows: Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

INSERT INTO table (column1, column2, .., columnn)

Chapter 12 (value1, - Oracle, SQLXML, and Other Data Providers VALUES value2, ...,.NET valunen) Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

For example, the following query a new record to the Customers table columns with their corresponding Chapter 15 - Using ADO.NET in Xml adds Web Services values:16 - ASP.NET Server Controls and Data Binding Chapter Chapter 17 - Building Real-World Web Applications Chapter INSERT 18 INTO - Object-Relational Customers(CompanyName, Mapping in .NET ContactName, ContactTitle,

Address, City, Objects: Phone)Performance VALUES ("New Name","New Title", Chapter 19 - Mapped Considerations and DataContact","New Binding "New Address", "New City", "New Phone") Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

You can also insert records in a table by selecting records from another table. You can do that by mixing INSERT INTO and SELECT statements. The only condition is that the data type of the columns must match in Appendix B - Commonly Used SQL Statements both tables. Appendix A - Relational Databases: Some Basic Concepts Appendix C - ADO.NET Frequently Asked Questions Index The syntax for this is as follows: List of Figures List of Tables INSERT INTO table1 (column1, column2, ...) List of Listings SELECT column1, column2, ... FROM table2 List of Sidebars

The previous syntax selects data from table2 and inserts it in table1. The data types of column1 in table1 must match with the data type of column1 in table2 and so on. The following query reads CustName and ContName from NewTable and inserts data to the Customers table: INSERT INTO Customers (CustomerName, ContactName) SELECT CustName, ContName FROM NewTable

You can also apply WHERE and other clauses on this query as you have applied them on the previous SELECT statements.


Using Joinsby and Aliases Mahesh Chand and David Talbot

ISBN:1590590732


You can represent a table and column in a SQL statement using their alias names. Aliases are frequently This text provides extensive of syntax: ADO.NET technology used as shorthand-especially in join queries.coverage This is the including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to FROM integrate both with SELECT aliastable.column1 aliascolumn table aliastable ADO.NET.

For example, this code uses A1 as the alias for the Customers table:

Table of Contents


SELECT A1.CustomerID FROM Customers A1;


- ADO.NET Basics

Chapter - Data Components Studio .NET Figure 2B-12 shows the outputinofVisual this statement. You can use the same syntax for multiple tables by separating Chapter 3 -commas. ADO.NET in Disconnected Environments them with Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure B-12: Output of the Alias statement


Chapter 18 useful - Object-Relational Mapping in .NET Joins are when you need to select data from multiple tables based on selection criteria from more than Chapter 19 -For Mapped Objects: Considerations Data and Binding one table. example, you Performance want to select data from theand Orders Customers tables where the CustomerID Chapter column20 in -the COM Customers Interoperability table exists and ADO.NET in the CustomerID column of the Orders table as a foreign key. The

following returns you the result: Chapter 21 statement - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix - Relational Databases: Some Basic Orders.CustomerID, Concepts SELECTA DISTINCT Orders.OrderID, Orders.EmployeeID, Appendix Customers.CompanyName, B - Commonly Used SQL Customers.Address, Statements Customers.City

FROM Customers JOIN Orders ON Customers.CustomerID = Orders.CustomerID; Appendix C - ADO.NET INNER Frequently Asked Questions Index List of Figures

The output of this statement looks like Figure B-13.

List of Tables


Figure B-13: Output of the JOIN statement


There are a handful of different types of joins, the most important of which are inner joins, outer joins, and ISBN:1590590732 by Mahesh Chand and David Talbot cross joins. Apress © 2003 (928 pages)

Inner joins returnThis records text when provides both extensive tables have coverage at least of ADO.NET one row technology that satisfies the join condition. including ADO.NET internals, namespaces, classes, and interfaces, takes a comprehensive look at XMLJOIN, and FULL (OUTER) JOIN clauses. Outer joins work with LEFT and (OUTER) JOIN,RIGHT (OUTER) namespaces and classes, how tofrom integrate bothtable with and null values for the unmatched OUTER JOIN with RIGHT JOIN return alland records the right ADO.NET. records in the left table. The OUTER JOIN with LEFT JOIN clause is the reverse of the OUTER JOIN with RIGHT JOIN clause. It returns all records from the left table and null values for the unmatched records in the rightof table. The OUTER JOIN with the FULL JOIN clause returns all records from both tables. If there's no Table Contents match for a record of the Data-Driven left table in Solutions the right table, the right table returns null values and vice versa. Applied ADO.NET—Building Introduction

Cross joins return all records from the left table, and each row of the left table is combined with all records of - ADO.NET Basics the right table.

Chapter 1 Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



AppliedViews ADO.NET: Building Data-Driven Solutions Understanding by Mahesh Chand and David Talbot

ISBN:1590590732

Aview is a virtual Apress table that represents © 2003 (928 pages)data from one or more than one database table. You can select data from single or multiple tables based on the sort and filter criteria (using WHERE and GROUP BY clauses) and This text provides extensive coverage of ADO.NET technology save data as a view. You can also set permissions on views to control access to sensitive data. For example, including ADO.NET internals, namespaces, classes, and interfaces, and a comprehensive look all at use XML the same database. The manager can a manager, an accountant, and takes a clerk of a company can namespaces classes, how to integrate both with access all data from differentand tables of theand database, the accountant can access only some of the data from ADO.NET. multiple tables, and the clerk can access only some of a single table's data. The easiest way to do this is with SQL views; you create three different views based on the user rights and let the user access these views based their rights. Table of on Contents Applied ADO.NET—Building Data-Driven Solutions

Note Access databases don't natively support SQL views. You'll need to use a "true" relational database to explore views, such as SQL Server and its copy of Northwind.


- ADO.NET Basics

Chapter 2 - Data Components in Visual Studioa.NET TheCREATE VIEW SQL statement creates view. The simple format of the CREATE VIEW statement is as Chapter follows:3 - ADO.NET in Disconnected Environments Chapter 4


Chapter 5 VIEW - Handling ADO.NET CREATE viewname AS Events selectstatement Chapter 6 - Integrating XML with ADO.NET Chapter 7


where viewname is theand name of Relations the view and selectstatement is the SELECT statement used to select Chapter 8 - Constraints Data data from one or more table. Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider

The following CREATE VIEW statement creates myView with records as a result of SELECT myName FROM

Chapter 11 - Stored Procedures and Views myTable:


CREATE VIEW myView AS SELECT myName FROM myTable


Chapter 16 - ASP.NET Server Controls and Data Binding The following two CREATE VIEW statements create the View1 view and the View2 view from the Orders Chapter 17 Building Real-World Web Applications table based on different criteria: Chapter 18 - Object-Relational Mapping in .NET Chapter 19 VIEW - Mapped Objects:AS Performance Considerations and Data Binding CREATE "View1" Chapter 20 OrderID, - COM Interoperability and ADO.NET SELECT OrderDate, ShippedDate Chapter 21 - Messaging FROM Orders Chapter WHERE22(Freight - SQL Server < and 10)ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

CREATEC VIEW "View2" AS Asked Questions Appendix - ADO.NET Frequently SELECT OrderID, OrderDate, ShippedDate Index FROM Orders List of Figures WHERE (Freight > 1000)

List of Tables

List of Listings List of can Sidebars You also create views by selecting data from multiple tables. For example, the following view selects

data from the Products and Categories tables. By using views this way, you can essentially "save" frequently used queries: CREATE VIEW "Products by Category" AS SELECT Categories.CategoryName, Products.ProductName, Products.QuantityPerUnit, Products.UnitsInStock, Products.Discontinued FROM Categories INNER JOIN Products ON Categories.CategoryID = Products.CategoryID WHERE Products.Discontinued 1 ORDER BY Categories.CategoryName, Products.ProductName


Note You may heard theand termDavid materialized wondered what it was. Basically, a by have Mahesh Chand Talbot view and ISBN:1590590732 materialized view is a view that's been stored (in many ways defeating the original goal of views as Apress © 2003 (928 pages) being virtual tables, but that's another issue). SQL Server calls its materialized views indexed This text provides extensive coverage of ADO.NET technology views, and although you can create indexed views with any including ADO.NET internals, namespaces, classes, andversion of SQL Server, only the interfaces, and takes a comprehensive look XML A SQL Server indexed view is essentially a enterprise, developer, and evaluation editions useatthem. namespaces and how to integrate both with view that has had a and set classes, of unique values "materialized" into the form of a clustered index, thereby ADO.NET. providing a quick lookup in terms of pulling the information behind a view together. Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



ADO.NET: Building Data-Driven Solutions Using SQL Applied Server's SELECT...FOR XML Clause by Mahesh Chand and David Talbot

ISBN:1590590732

Most of today's databases support Extensible Markup Language (XML). In SQL Server, for example, you Apress © 2003 (928 pages) can execute SQLThis queries to return results ascoverage XML rather than standard rowsets. You can execute these text provides extensive of ADO.NET technology queries directly orincluding from within stored procedures. To retrieve results directly, you use the FOR XML clause ADO.NET internals, namespaces, classes, and interfaces,Within and takes a comprehensive XML one of three XML modes: RAW, AUTO, of the SELECT statement. the FOR XML clause,look you at specify namespaces and classes, anddata howintoAccess, integrate both with or EXPLICIT. (You can also work with XML Oracle, MySQL, and other databases, but the ADO.NET. techniques vary.) For example, this SQL Server SELECT statement retrieves information from the Customers and Orders tables in the Northwind database:

Table of Contents


SELECT ContactName, CompanyName, Chapter 1 Customers.CustomerID, - ADO.NET Basics Orders.CustomerID, OrderDate - Data Components in Visual Studio .NET FROM Customers, Orders Chapter 3 - ADO.NET in Disconnected Environments WHERE Customers.CustomerID = Orders.CustomerID Chapter 4 - ADO.NET in Connected Environments AND (Customers.CustomerID = "NALFKI" Chapter 5 - Handling ADO.NET Events OR Customers.CustomerID = "NXYZAA") Chapter 6 - Integrating XML with ADO.NET ORDER BY Customers.CustomerID Chapter 7 -AUTO Data Binding and Windows Forms Data-Bound Controls FOR XML Chapter 2

Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Understanding Data Providers SQL Injection Chapter 13 - Developing a Custom Data Provider

SQL injection is the process of using SQL queries and failing because of invalid user input. SQL injection is usually caused by the code written by developers. For example, let's say a form has a Chapter 15 - Using ADO.NET in Xml Web Services TextBox1 control and developers use the text of TextBox1 as one of the SQL query variables: Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

string str = "SELECT * FROM Table WHERE Name ='" + TextBox1.Text + "'";


Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 what - Messaging Now, happens when Amie O'Donell enters her name in TextBox1? The execution of the SQL Chapter 22 SQL and of ADO.NET: Notes on Performance query -will failServer because invalid SQL syntax. You have to be careful when building and executing Appendix A -SQL Relational Databases: direct queries. You can Some simplyBasic avoidConcepts this by checking if the user input has an invalid character in Appendix it. B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions IndexAnother common scenario is when the database server is expecting a number value and the user

enters a string value or vice versa. This could lead to a failure if you don't have a check in the code. For example, you could use the ToString method to make sure the input is a valid query (using the List of Tables Convert class to convert from one data type to another). List of Figures

List of Listings

List of Sidebars

Summary


ISBN:1590590732

In this appendix, we discussed some commonly used SQL statements. You can access the following Apress © 2003 (928 pages) resources online:This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

"A Gentle Introduction SQL" byaAndrew Cumming: interfaces, to and takes comprehensive lookhttp://sqlzoo.net at XML namespaces and classes, and how to integrate both with

Microsoft SQL ADO.NET. Server product documentation: www.microsoft.com/sql/techinfo/productdoc/2000/default.asp Table of Contents Peter Gulutzan's Ocelot SQL site: www.ocelot.ca Applied ADO.NET—Building Data-Driven Solutions

"SQL Tutorial" at W3Schools: www.w3schools.com/sql/default.asp Introduction Chapter 1

ADO.NET Basics "Trees- in SQL" by Joe Celko: www.intelligententerprise.com/001020/celko1_1.shtml

Chapter 2


Chapter The 3 SQL - ADO.NET Tutorialinsite Disconnected by Chuo-Han Environments Lee: www.1keydata.com/sql/sql.html Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Building Data-Driven Solutions AppendixApplied C: ADO.NET: ADO.NET Frequently Asked Questions ISBN:1590590732 by Mahesh Chand and David Talbot

Overview


This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and In this appendix, we'll interfaces, answer and some takesofathe comprehensive commonly asked look atquestions XML related to ADO.NET. Most of these namespaces andon classes, and how to integrate both with questions were originally asked C# Corner discussion forums (www.c-sharpcorner.com) or other ADO.NET.

newsgroups.

Q: FAQ 1: How can I obtain a database schema programmatically?

Table of Contents


Q: FAQ 2: How can I obtain table schema using a Command object? Introduction Chapter 1

- ADO.NET Basics

Chapter 2 3: - Data in Visual .NETplus (+) sign in a DataGrid? Q: FAQ HowComponents can I get rid Studio of the Chapter 3 - ADO.NET in Disconnected Environments Chapter 4

- ADO.NET in Connected Environments Q: FAQ 4: How do I hide a DataTable column?

Chapter 5


Chapter 6


Chapter 7


Q: FAQ 5: How can I insert dates in a SQL statement?

Chapter 8

- Constraints and Data Relations Q: FAQ How can I getHandling columns names and their data types from a DataSet? Chapter 9 6: - ADO.NET Exception Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 7: - Stored and Views Q: FAQ How Procedures can I find out how many rows are in a DataGrid? Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 8: - Developing Data Provider Q: FAQ How do aI Custom implement paging in ADO.NET? Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Q: FAQ 9: How do I implement transactions in the OleDb data provider?


Q: FAQ How can I Mapping create inAutoIncrement columns? Chapter 18 10: - Object-Relational .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter Q: FAQ 20 11: - COM How Interoperability can I copy and aADO.NET DataSet's contents? Chapter 21 - Messaging Chapter 22 12: - SQLHow Server andIADO.NET: Notes(*) on Performance Q: FAQ can use Count to count number of rows? Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Q: FAQ 13: How do I get a database schema using a DataSet programmatically?


List Figures Q:ofFAQ 14: How does SELECT DISTINCT work, and how is it related to List ofduplicates? Tables List of Listings List Sidebars Q:ofFAQ 15: How do I read and write to the Windows Registry in .NET?

Q: FAQ 16: How can I obtain ODBC Data Source Names (DSNs)? Q: FAQ 17: How can I read and write bitmaps or BLOB data? Q: FAQ 18: What are DiffGrams and how do they relate to DataSets? How do I read and write DiffGrams using a DataSet? Q: FAQ 19: How does CommandBehavior work?

Applied Data-Driven Solutions in a DataReader? Q: FAQ 20: How can ADO.NET: I count Building total number of records by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

Q: FAQ 21: How can I find out the end of file in a DataReader? This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, takesrecords a comprehensive at XML Q: FAQ 22: How can I and sort using look a DataReader? namespaces and classes, and how to integrate both with ADO.NET.

Q: FAQ 23: What's the fastest way to figure out connection strings for different data providers? Table of Contents Applied ADO.NET—Building Data-Driven Solutions Answers Introduction Chapter 1

- ADO.NET Basics

usingComponents the OleDb data provider, can use the GetOleDbSchemaTable method of the A: If you're Chapter 2 - Data in Visual Studioyou .NET OleDbConnection object. Unfortunately, the Chapter 3 - ADO.NET in Disconnected Environments Sql data provider doesn't support this method. However, you can4use sysobjects as a table name in your SELECT statement, which returns all the tables stored in a Chapter - ADO.NET in Connected Environments database for SQL Server. Chapter 5 - Handling ADO.NET Events Chapter 6


A: You can get a database table schema by executing a SqlCommand object. Actually, the IDataReader Data Binding and Windows Forms Data-Bound Controls object -helps you to return a table schema with the help of its GetSchemaTable method. You know that the Chapter 8 - Constraintsmethod and Data ExecuteReader ofRelations SqlCommand returns an IDataReader (or SqlDataReader) object. When Chapter 9 ADO.NET Exception Handling you want a table schema, you need to pass CommandBehavior.SchemaOnly as the only argument of Chapter 10 - Working with the ODBC .NET Data Provider ExecuteReader, which returns a DataTable with the schema of a database table. Chapter 7


Listing reads a database table .NET schema, Chapter 12 -C-1 Oracle, SQLXML, and Other Data displays Providersit in a DataGrid control, and lists all the columns of a table ListBoxacontrol. Chapter 13in- a Developing Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Listing C-1: Getting a Database Table Schema Using SqlCommand



conn New SqlConnection(connectionString) Chapter 17 -=Building Real-World Web Applications conn.Open() Chapter 18 - Object-Relational Mapping in .NET sql = "SELECT * FROM Employees" Dim cmd As SqlCommand = New SqlCommand(sql, conn) Chapter 20 - COM Interoperability and ADO.NET Dim reader As IDataReader = _ Chapter 21 - Messaging cmd.ExecuteReader(CommandBehavior.SchemaOnly) Chapter 22 - SQL Server and ADO.NET: Notes on Performance Dim schemaTable As DataTable = New DataTable() Appendix A - Relational Databases: Some Basic Concepts schemaTable = reader.GetSchemaTable Appendix B - Commonly Used SQL Statements DataGrid1.DataSource = schemaTable Appendix - ADO.NET Frequently Questions Dim CrowCollection As Asked DataRowCollection = _ Indexreader.GetSchemaTable().Rows List ofDim Figures row As DataRow List ofFor Tables Each row In rowCollection List of Listings str = row("ColumnName") ListBox1.Items.Add(str) List of Sidebars Next conn.Close()


TheGetSchemaTable method returns meta-data about each column. Table C-1 defines the metadata and column order. Table C-1: IDataReader Meta-Data

COLUMN NAME DESCRIPTION Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot This is the name of the column. Apress © 2003 (928 pages)

ColumnName

ColumnOrdinal This text provides This isextensive the ordinal coverage of the column. of ADO.NET Thistechnology is zero for the bookmark column of including ADO.NET internals, namespaces, and the row, if any. Other columnsclasses, are numbered starting with one. This column interfaces, and takes a comprehensive look at XML can't contain a null value. namespaces and classes, and how to integrate both with ColumnSizeADO.NET. This is the length of the column.

NumericPrecision Table of Contents

If ProviderType is a numeric data type, this is the maximum precision of the column.


If ProviderType is DBTYPE_DECIMAL or DBTYPE_NUMERIC, this is the number of digits to the right of the decimal point. Otherwise, this is a null Chapter 1 - ADO.NET Basics value. NumericScale Introduction Chapter 2


Chapter 3 - ADO.NET in Disconnected Environments DataType This is the data type of the column (the .NET Framework data type). Chapter 4 - ADO.NET in Connected Environments

ProviderType

Chapter 5

This is the indicator of column's data type.


Chapter IsLong 6 - Integrating XML with YouADO.NET can use this to find out if a column contains a Binary Long Object Chapter 7

contains very long data. - Data Binding and (BLOB) Windowsthat Forms Data-Bound Controls

Chapter 8


Chapter 9


AllowDBNull

This is true if a column can contain null values; otherwise, it's false.

true if a Provider column is read only; otherwise, it's false. IsReadOnly Chapter 10 - Working with the This ODBCis.NET Data Chapter 11 - Stored ProceduresThis andisViews true if the column contains a persistent row identifier that can't be IsRowVersion Chapter 12 - Oracle, SQLXML, and Other written to, .NET and itData hasProviders no meaningful value except to identity the row. Chapter 13 - Developing a Custom Data Provider

ThisWeb is true if the column has unique values, which means no two rows IsUnique Chapter 14 - Developing Database Applications using ASP.NET values Chapter 15 - Using ADO.NET incan Xmlhave Web same Services Chapter 16 - ASP.NET Server Controls and Data Binding This is true if the column is one of a set of columns in the rowset that, IsKeyColumn Chapter 17 - Building Real-World Web Applications taken together, uniquely identify the row. Chapter 18 - Object-Relational Mapping in .NET

IsAutoIncrement

This is true if a column is auto-incrementing.


Chapter 20 - COM Interoperability ADO.NET BaseSchemaName Thisand is the name of the schema in the data store that contains the column. Chapter 21 - Messaging This is a null value if you can't determine the base schema name. Chapter 22 - SQL Server and ADO.NET: Notes on Performance

BaseCatalogName

This is the name of the catalog in the data store that contains the column. This is a null value if you can't determine the base catalog name.


BaseTableName ThisAsked is theQuestions name of the table or view in the data store that contains the Appendix C - ADO.NET Frequently Index

column. This is a null value if you can't determine the base table name.

List of BaseColumnName Figures List of Tables

This is the name of the column in the data store. This might be different from the column name returned in the ColumnName column if you used an alias.


ADO.NET: Building Solutions a DataGrid control using a Data-Driven DataSet'sDefaultViewManager, the DataGrid control A: When you fill Applied ISBN:1590590732 by(+) Mahesh and you David Talbot it and see all displays a plus sign, Chand which lets expand the available tables in a collection. You can Apress © 2003 (928binding pages) a DataGrid with the DefaultViewManager. Instead, you can read easily avoid the + sign by not each DataTable fromprovides the collection andcoverage bind them programmatically. This text extensive of ADO.NET technology including ADO.NET internals, namespaces, classes, and and takesds. a comprehensive lookfollowing at XML method: Say you haveinterfaces, a DataSet called You can use the namespaces and classes, and how to integrate both with ADO.NET.

dataGrid1.DataSource = ds.Tables["TableName"]; Table of Contents

or you can use the following: Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter dataGrid1.DataSource 1 - ADO.NET Basics = ds.Tables[index]; Chapter 2


Chapter 3

- ADO.NET in Disconnected Environments property of a DataTable represents a collection of columns in a DataTable. You can get A: The4Columns Chapter - ADO.NET in Connected Environments

aDataColumn from this collection by using a column index or the name of the column. Setting the - Handling ADO.NET Events Visible property to false hides a column, and setting it to true displays the column:

Chapter 5 Chapter 6


Chapter 7


DataTable.Columns(index).Visible = false; Chapter 8 - Constraints and Data Relations Chapter 9



A: The following code shows how to construct a SQL statement with date values in it. You can simply execute this query:



Dim sql As String = "INSERT INTO Table (col1, [date], col2)" & _ " VALUES(4588, #01/02/02#, 'some value')"


Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17common - Building Real-World Webwant Applications A: It's a need when you to find out how many columns (and their names and data types) that a Chapter 18 - Object-Relational Mapping in .NET DataSet or a DataTable contains. You can get DataTable columns through the Columns property, Chapter 19 returns - Mapped Considerations and has Datamultiple Binding tables, you use the DataSet.Tables which allObjects: columnsPerformance as a collection. If a DataSet Chapter 20 - COM Interoperability and ADO.NET property, which returns a collection of DataTable objects as a collection of DataTables. To get a Chapter DataTable 21 - Messaging from a collection, you can either use the table name or use the table index. Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Once you get a collection of columns of a DataTable, you can read each column one by one and get DataColumn member values. To find out the data type of a DataColumn, you can use the DataType Appendix B - Commonly Used SQL Statements property. If you want to compare whether a column is a string, integer, or other type, you can compare its Appendix C - ADO.NET Frequently Asked Questions DataType property with Type.GetType(). Appendix A - Relational Databases: Some Basic Concepts

Index

List ofListing Figures C-2 reads a DataTable's columns and checks if a column is a string type. List of Tables List ofListing ListingsC-2: ReadingDataSet Columns and Their Data Types List of Sidebars

' Add Table columns to the dropdownlistbox Dim cols As DataColumnCollection = ds.Tables(0).Columns Dim col As DataColumn For Each col In cols searchDropDown.Items.Add(col.ColumnName) ' add only string type columns, otherwise If (col.DataType Is Type.GetType("System.String")) Then ' do something Else ' else do something End If

Next Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

This a text provides extensiveobject coverage of ADO.NET BindingManager associated withtechnology it. You can use the Count property of A: Each control has including ADO.NET internals, namespaces, classes, and BindingManager: interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Dim rowsADO.NET. As Integer = _

dtGrid.BindingContext(dtGrid.DataSource, _ dtGrid.DataMember).Count

Table of Contents


A: Paging is a processing of fetching a number of rows as a page (a subset of data) instead of all rows from a

Chapter - ADO.NET data1 source. You Basics can achieve paging in two ways in ADO.NET: by using a DataAdapter and by using a Chapter 2 statement. - Data Components in Visual Studio .NET SQL Chapter 3

- ADO.NET in Disconnected Environments Paging a DataAdapter Chapter 4 - Using ADO.NET in Connected Environments Chapter 5


TheFill method of DataAdapter provides an overloaded form where you can ask the DataAdapter to - Integrating XML with ADO.NET return only a selected number of rows in a DataSet. The overloaded form of the Fill method is as Chapter 7 - Data Binding and Windows Forms Data-Bound Controls follows: Chapter 6 Chapter 8


Chapter 9


Overloads Public Function Fill(ByVal dataSet As DataSet, _ ByVal startRecord As Integer, _ Chapter 11 - Stored Procedures and Views ByVal maxRecords As Integer, _ Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers ByVal srcTable As String _ Chapter 13 -Integer Developing a Custom Data Provider ) As Chapter 10 - Working with the ODBC .NET Data Provider


where a DataSet fill with Chapter 16 dataSet - ASP.NET is Server Controlstoand Datarecords Binding and, if necessary, schema; startRecord is the zerobased number to start with; maxRecords is the maximum number of records to retrieve; and Chapter 17 -record Building Real-World Web Applications srcTable is the name ofMapping the source table to use for table mapping. Listing C-3 shows a function that Chapter 18 - Object-Relational in .NET returns DataSet filled Performance with the records based on the passed in the method. Chapter 19 - aMapped Objects: Considerations andpage Data size Binding Chapter 20 - COM Interoperability and ADO.NET

Listing C-3: GetPageData Method



Function GetPagedData(ByVal daConcepts As SqlDataAdapter, _ Appendix A - Relational Databases: Some Basic ByVal idx As Integer, ByVal size As Integer) As DataSet Dim ds As DataSet = New DataSet() Appendix C - ADO.NET Frequently Asked Questions Try Index da.Fill(ds, idx, size, "Orders") List of Figures Catch e As Exception List of Tables MessageBox.Show(e.Message.ToString()) List of Listings End Try List of Sidebars Return ds End Function Appendix B - Commonly Used SQL Statements

Paging Using the SELECT TOP SQL Statement Besides the Fill method of a DataAdapter, you can even use a SELECT SQL statement to retrieve the number of records from a table. You use the SELECT TOP statement for this purpose. The following statement selects the top 10 records from the Customers table. You set the SELECT statement as the SELECT TOP statement:

"SELECT TOP 10 CustomerID, CompanyName, " & _ Applied ADO.NET: Data-Driven " ContactName FROMBuilding Customers ORDER Solutions BY CustomerID" by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

ImplementingThis Paging text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Finally, let's see how to use both the previously discussed methods to implement paging in ADO.NET. The namespaces and Figure classes,C-1. and In how integrate sample application looks like thistofigure, youboth can with enter the number of rows you want to load ADO.NET. in a page. The Load Page button loads the first page. The Previous Page and Next Page buttons load those pages from database. When you check the SELECT TOP check box, the program uses the SELECT TOP otherwise, it uses the DataAdapter'sFill method. Tablemethod; of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Figure C-1: Paging in an ADO.NET application


Listing C-4 implements paging using both methods. As you can see from this code, the Load Page button

Chapter - ASP.NET Server Controls andsize, Datacreates Bindingand opens a new connection, and checks whether the click16event handler reads the page Chapter 17 Building Real-World Web Applications SELECT TOP check box is checked. If it is, it calls the GetTopData method; otherwise, it calls the Chapter 18 - Object-Relational GetPagedData method.Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Listing in ADO.NET Chapter 20 - C-4: COM Implementing Interoperability Paging and ADO.NET Chapter 21 - Messaging Chapter 22 - SQLSub Server and ADO.NET: Notes on Performance Private LoadPageBtn_Click(ByVal sender As System.Object, _ Appendix A Relational Databases: Some BasicHandles Concepts LoadPageBtn.Click ByVal e As System.EventArgs) Appendix pageSize B - Commonly = Convert.ToInt32(TextBox1.Text.ToString()) Used SQL Statements

' CCreate and open aAsked connection Appendix - ADO.NET Frequently Questions Index

conn = New SqlConnection(connectionString)

conn.Open() List of Figures ' Find out total number of records List of Tables Dim cmd As SqlCommand = New SqlCommand() List of Listings ' Assign the SQL Insert statement we want to execute to the CommandText cmd.CommandText = "SELECT Count(*) FROM Customers" cmd.Connection = conn ' Call ExecuteNonQuery on the Command Object to execute insert totalRecords = cmd.ExecuteScalar() ' Create data adapter sql = "SELECT CustomerID, CompanyName, ContactName " & _ "FROM Customers ORDER BY CustomerID" adapter = New SqlDataAdapter(sql, conn) ds = New DataSet() ' If SELECT TOP check box is checked If CheckBox1.Checked Then selectTop = True

List of Sidebars

Else Applied Building Data-Driven Solutions selectTop = ADO.NET: False ISBN:1590590732 by Mahesh Chand and David Talbot End If Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology ' if SELECT TOP is checked including ADO.NET internals, namespaces, classes, and If selectTop Then interfaces, and takes a comprehensive look at XML GetTopData("", 0) classes, and how to integrate both with namespaces and DataGrid1.DataSource = custTable ADO.NET. Else ds = GetPagedData(adapter, curIndex, pageSize) Table of Contents curIndex = curIndex + pageSize Applied ADO.NET—Building Data-Driven Solutions DataGrid1.DataSource = ds.DefaultViewManager Introduction End If Chapter - ADO.NET Basics End1 Sub Chapter 2


' Get a page in using SELECT TOP statement Chapter 3 - ADO.NET Disconnected Environments Public Sharedin Sub GetTopData(ByVal selectCmd As String, ByVal type As Integer) Chapter 4 - ADO.NET Connected Environments time load Events first TOP pages Chapter '5 First - Handling ADO.NET Then Chapter If 6 -(selectCmd.Equals(String.Empty)) Integrating XML with ADO.NET "SELECT " Data-Bound & pageSize & " CustomerID, CompanyName, " & _ Chapter 7 selectCmd - Data Binding= and WindowsTOP Forms Controls "- Constraints ContactName FROM Customers ORDER BY CustomerID" and Data Relations End If

Chapter 8 Chapter 9



totalPages = CInt(Math.Ceiling(CDbl(totalRecords) / pageSize)) adapter.SelectCommand.CommandText = selectCmd Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Dim tmpTable As DataTable = New DataTable("Customers") Chapter Dim 13 - Developing a Custom Data recordsAffected As Provider Integer = adapter.Fill(tmpTable) Chapter '14If - Developing Database Web ASP.NET the table does notApplications exist, using create it. Chapter If 15 -custTable Using ADO.NET in Xml Web Services Is Nothing Then custTable = tmpTable.Clone() Chapter '16Refresh - ASP.NET the Server Controls Binding table ifand atData least one record is returned. Chapter If 17 -recordsAffected Building Real-World Web Applications > 0 Then Chapter 18Select - Object-Relational Case type Mapping in .NET Case 1Objects: Performance Considerations and Data Binding Chapter 19 - Mapped currentPage currentPage + 1 Chapter 20 - COM Interoperability=and ADO.NET Case 2 Chapter 21 - Messaging = currentPage - 1 Chapter 22 - SQLcurrentPage Server and ADO.NET: Notes on Performance Case Else Appendix A - Relational Databases: Some Basic Concepts currentPage = 1 Appendix B - Commonly Used SQL Statements End Select Appendix C - ADO.NET Frequently Asked Questions ' Clear the rows and add new results. Index custTable.Rows.Clear() List of Figures ' Import rows from temp tabke to custTable List of Tables Dim myRow As DataRow List of Listings For Each myRow In tmpTable.Rows List of Sidebars custTable.ImportRow(myRow) Next ' Preserve the first and last primary key values. Dim ordRows() As DataRow = custTable.Select("", "CustomerID ASC") firstVisibleCustomer = ordRows(0)(0).ToString() lastVisibleCustomer = ordRows(custTable.Rows.Count - 1)(0).ToString() End If End Sub Chapter 11 - Stored Procedures and Views

' Previous page button click Private Sub PrePageBtn_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles PrePageBtn.Click

' if SELECT TOP is checked AppliedThen ADO.NET: Building Data-Driven Solutions If selectTop ISBN:1590590732 by Mahesh Talbot & " CustomerID, sql = "SELECT Chand TOP "and & David pageSize CompanyName, " & _ Apress © 2003 (928 pages) " ContactName FROM Customers " & _ text provides < extensive coverage of ADO.NET technology "WHEREThis CustomerID '" & firstVisibleCustomer & "' ORDER BY CustomerID" including ADO.NET internals, namespaces, classes, and GetTopData(sql, 1) interfaces, and takes a comprehensive look at XML Else namespaces and classes, and how to integrate both with ds = GetPagedData(adapter, curIndex, pageSize) ADO.NET. curIndex = curIndex - pageSize DataGrid1.DataSource = ds.DefaultViewManager Table ofEnd Contents If Applied ADO.NET—Building Data-Driven Solutions Introduction End Sub Chapter 1

- ADO.NET Basics

Chapter ' Next 2 - Data page Components button in click Visual Studio .NET

Private Sub NextPageBtn_Click(ByVal sender As System.Object, _ Chapter 3 - ADO.NET in Disconnected Environments ByVal e As System.EventArgs) Handles NextPageBtn.Click Chapter 4 - ADO.NET in Connected Environments SELECTADO.NET TOP is checked Chapter '5 if - Handling Events Then Chapter If 6 -selectTop Integrating XML with ADO.NET = Binding "SELECT " &Forms pageSize & " Controls CustomerID, CompanyName, " & _ Chapter 7 sql - Data and TOP Windows Data-Bound "- Constraints ContactName FROM Customers " & _ and Data Relations "WHERE CustomerID > '" & lastVisibleCustomer & "' ORDER BY CustomerID" Chapter 9 - ADO.NET Exception Handling GetTopData(sql, 2) Chapter 10 - Working with the ODBC .NET Data Provider Else Chapter 11 - Stored Procedures and Views ds = GetPagedData(adapter, curIndex, pageSize) Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers curIndex = curIndex + pageSize Chapter 13DataGrid1.DataSource - Developing a Custom Data Provider = ds.DefaultViewManager Chapter End 14 - Developing Database Web Applications using ASP.NET If Chapter - Using ADO.NET in Xml Web Services End15Sub Chapter 8


The19 GetTopData method uses the SELECT TOP SQL to get the top records, creates a DataTable Chapter - Mapped Objects: Performance Considerations andquery Data Binding custTable, and reads dataand in this table from the main DataTable tmpTable, which has all records Chapter 20 - COM Interoperability ADO.NET from database table. Chapter 21the - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Now, if you see the Previous Page and Next Page button click handlers, you'll see that it's just a matter of

Appendix A -GetTopData Relational Databases: Some Basic Concepts calling and GetPagedData with the current record number and number of records to be Appendix B Commonly Used SQL Statements fetched. Appendix C - ADO.NET Frequently Asked Questions IndexYou can download the complete source code from the Downloads section of the Apress Web site

for more details. List of(www.apress.com) Figures List of Tables

A: A transaction is a set of SQL SELECT , INSERT,UPDATE, and DELETE statements that are dependent on one another. For instance, say you can't delete and update some data until it's added to the database. So, List of Sidebars you combine all required SQL statements and execute them as a single transaction. If there are no errors during the transaction, all modifications in the transaction become a permanent part of the database. If errors are encountered, none of the modifications are made to the database. If a transaction was successful, the transaction was committed; otherwise, the transaction was rolled back. List of Listings

For example, in a banking application where funds are transferred from one account to another, one account is credited an amount and another account is debited the same amount simultaneously. Because computers can fail because of power outages, network outages, and so on, it's possible to update a row in one table but not in the related table. If your database supports transactions, you can group database operations into a transaction to prevent database inconsistency resulting from these outages. In ADO.NET, the Connection and Transaction objects handle transactions. Follow these steps to 1.

perform transactions: Appliedan ADO.NET: Data-Driven Solutions 1. After creating instance Building of a Connection class (no matter what data provider you choose), you ISBN:1590590732 by Mahesh Chand and David Talbot call the BeginTransaction method to start a transaction. The BeginTransaction method Apress © 2003 (928 pages) returns a Transaction object: This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Dim tran As OleDbTransaction = conn.BeginTransaction() interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

2. Create Command objects with the active transaction, set its Transaction property as the current transaction, and call its Execute method:

Table of Contents


Dim cmd As OleDbCommand = New OleDbCommand() cmd.Connection = conn Chapter 1 - ADO.NET Basics cmd.Transaction = tran Introduction Chapter 2


Chapter 3


Chapter 4 3. -Call ADO.NET the Commit in Connected and Rollback Environments methods to commit and roll back transactions using this code: Chapter 5


Chapter 6

-tran.Commit() Integrating XML with ADO.NET

Chapter 7

-tran.Rollback() Data Binding and Windows Forms Data-Bound Controls

Chapter 8


Chapter 9



shows you to use transactions in the OleDb data provider. Chapter 11 -Listing StoredC-5 Procedures andhow Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Listing C-5: Transactions in the OleDb Data Provider


Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 Sub - ASP.NET Server Controls and Data Binding Main() Chapter 17 Dim - Building Real-World Web Applications str As String Chapter 18 Dim - Object-Relational Mapping inAs .NET connectionString String = _ Chapter 19 - Mapped Objects: Performance Considerations and DataData Binding "Provider=Microsoft.Jet.OLEDB.4.0; Source=F:\\AppliedAdoNet.mdb" Chapter 20 '- COM Interoperability and Create and open a ADO.NET connection Chapter 21 Dim - Messaging conn As OleDbConnection = _

NewServer OleDbConnection(connectionString) Chapter 22 - SQL and ADO.NET: Notes on Performance Appendix A conn.Open() - Relational Databases: Some Basic Concepts

Start a Used transaction Appendix B '- Commonly SQL Statements tran Frequently As OleDbTransaction Appendix C Dim - ADO.NET Asked Questions = conn.BeginTransaction() Index List of List of List of List of

Dim cmd As OleDbCommand = New OleDbCommand() cmd.Connection = conn Figures cmd.Transaction = tran Tables Try Listings str = "INSERT INTO Users (UserName, UserDescription)" & _ Sidebars " VALUES ('New User', 'New Description')" cmd.CommandText = str cmd.ExecuteNonQuery() str = "UPDATE Users SET UserName = 'Updated User' WHERE " & _ " UserName = 'New User'" cmd.CommandText = str cmd.ExecuteNonQuery() str = "DELETE * FROM Users WHERE UserName = 'Updated User'" cmd.CommandText = str cmd.ExecuteNonQuery() ' Commit transaction tran.Commit()

Console.WriteLine("Changes saved.") Applied Building Data-Driven Solutions Catch e ADO.NET: As Exception ISBN:1590590732 by Mahesh Chand and David Talbot ' Rollback transaction Apress © 2003 (928 pages) tran.Rollback() This text provides extensive coverage of ADO.NET technology Console.WriteLine(e.Message.ToString()) including ADO.NET internals, namespaces, Console.WriteLine("No changesclasses, were and made to database.") interfaces, and takes a comprehensive look at XML Finally namespaces and classes, and how to integrate both with conn.Close() ADO.NET. conn.Dispose() End Try Table of Contents End Sub Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2 - Data Components in Visual Studio .NET A: Auto-incrementing columns are columns whose value increases automatically when a new record is added to the To create an auto-incrementing column, you set the DataColumn.AutoIncrement property Chapter 3 table. - ADO.NET in Disconnected Environments

totrue. The DataColumn willEnvironments then start with the value defined in the AutoIncrementSeed property, Chapter 4 - ADO.NET in Connected and5with each rowADO.NET added, Events the value of the AutoIncrement column increases by the value held in the Chapter - Handling AutoIncrementStep property of the column: Chapter 6 - Integrating XML with ADO.NET Chapter 7


Dim8 col1 As DataColumn = Chapter - Constraints and Data Relations DataTable.Columns.Add("CustomerID", typeof(Int32)) Chapter 9 - ADO.NET Exception Handling workColumn.AutoIncrement = true Chapter 10 - Working with the ODBC .NET Data Provider workColumn.AutoIncrementSeed = 1000 Chapter 11 - Stored Procedures and Views workColumn.AutoIncrementStep = 10Providers Chapter 12 - Oracle, SQLXML, and Other .NET Data Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

A: There are occasions when you don't want to mess with the original DataSet's data and instead want to copy data somewhere and work with it. The DataSet provides a Copy method that you can use to copy the Chapter Server and Data Binding data16of- aASP.NET DataSet to a Controls second DataSet. When you copy data, you can copy in different ways: You can Chapter 17 Building Real-World Web Applications create an exact copy of a DataSet including its schema, data, row state information, and row versions. You Chapter - Object-Relational Mapping in a .NET can18 also copy only affected rows of DataSet to a second DataSet. Another case may be when you only Chapter 19to- copy Mapped Objects: Performance and Data Binding want a DataSet schema, notConsiderations the data. Chapter 15 - Using ADO.NET in Xml Web Services


To create an exact copy of the DataSet including a DataSet schema and data, you can use the Copy Chapter 21 - Messaging method. For Server example: Chapter 22 - SQL and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Dim Bds2 As DataSet = Statements ds1.Copy() Appendix - Commonly Used SQL Appendix C - ADO.NET Frequently Asked Questions Index

TheGetChanges method gets the affected rows of a DataSet. The GetChanges method takes a DataRowState object, which has members including Added,Modified, and Deleted. Using this List of Tables method, you can create a new DataSet from an existing DataSet with all rows that have been modified, List of Listings or you can specify new added, deleted, or modified rows. List of Figures

List of Sidebars

To create a copy of a DataSet that includes schema and only the data representing the Added, Modified, or Deleted rows, use the GetChanges method of the DataSet. You can also use GetChanges to return only rows with a specified row state by passing a DataRowState value when calling GetChanges. The following code shows how to pass a DataRowState when calling GetChanges: ' Copy all changes. Dim ds2 As DataSet = ds1.GetChanges() ' Copy only new rows. Dim ds2 As DataSet = ds1.GetChanges(DataRowState.Added) ' Copy only updated rows.

Dim ds2 As DataSet = ds1.GetChanges(DataRowState.Modified) Applied ADO.NET: Building Data-Driven Solutions ' Copy only deleted rows. ISBN:1590590732 by Mahesh Chand and David Talbot Dim ds2 As DataSet = ds1.GetChanges(DataRowState.Deleted) Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology including internals, classes, andan existing DataSet without copying its TheClone method of aADO.NET DataSet createsnamespaces, a new DataSet from interfaces, and takes a comprehensive look at XML data: namespaces and classes, and how to integrate both with ADO.NET.

Dim ds2 As DataSet = ds1.Clone() Table of Contents Applied ADO.NET—Building Solutions the number ofData-Driven records using a DataSet is pretty simple. A DataSet is a set of DataTable A: Getting Introduction objects, and a DataTable'sRows property represents the number of records in a DataTable. The Chapter following 1 - ADO.NET code retrieves Basics the number of rows of the first table of a DataSet. Similarity, you can retrieve the

number of records from other tables if a DataSet contains more than one DataTable object: Chapter 2 - Data Components in Visual Studio .NET Chapter 3


Chapter - ADO.NET in Connected Environments Dim4 ds As DataSet = New DataSet() Chapter 5 - Handling ADO.NET Events adapter.Fill(ds, "Employees") Chapter Dim6 counter - Integrating AsXML Integer with ADO.NET = ds.Tables(0).Rows.Count

MessageBox.Show(counter.ToString()) Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Chapter 8


Chapter 9


Retrieving the number of records using a DataReader is little tricky. You use the SELECT Count * SQL statement and execute the SQL statement using the ExecuteScalar method of the Command object. The Chapter 11 - Stored Procedures and Views following code returns the number of records using the Count * statement: Chapter 10 - Working with the ODBC .NET Data Provider


Dim cmd As OleDbCommand = _ New OleDbCommand("SELECT Count(*) FROM Orders", conn) Chapter 15 - Using ADO.NET in Xml Web Services Dim counter As Integer = CInt(cmd.ExecuteScalar()) Chapter 16 - ASP.NET Server Controls and Data Binding MessageBox.Show(counter.ToString()) Chapter 14 - Developing Database Web Applications using ASP.NET


Chapter 19 - when Mapped Objects: Performance Considerations Data A: Usually you work with databases, you already and know theBinding database schema such as database tables, Chapter 20columns, - COM Interoperability and ADO.NET table and column properties. What if you don't know the database schema, and you need to get a Chapter 21 - Messaging database's tables, columns, and column properties programmatically? Chapter 22 - SQL Server and ADO.NET: Notes on Performance

In this we show you how to access a database schema programmatically. As you can see from Appendix A sample - Relational Databases: Some Basic Concepts

Figure C-2, we created a Windows application with one TextBox control, three Button controls, and two ListBox controls. The Browse button lets you browse .mdb databases on your machine. The Get Tables Appendix C - ADO.NET Frequently Asked Questions button then reads the database tables and adds them to the first list box. The Get Table Schema button Index returns the table columns and the properties of the selected table in list box. Appendix B - Commonly Used SQL Statements



Figure C-2: Getting a database schema programmatically

Listing C-6 shows the source code for this application. As you can see, the BrowseBtn_Click handler Applied ADO.NET: Building Data-Driven Solutions browses Access databases on the machine, fills the selected database name to the text box, and sets ISBN:1590590732 by database Mahesh Chand and David dbName as the name, which is Talbot a string type of variable defined as follows: Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology

private string dbName = ""; including ADO.NET internals, namespaces, classes, and


Listing C-6: Reading a Database Schema Programmatically Table of Contents

Private Sub Browse_Click(ByVal Applied ADO.NET—Building Data-Driven Solutions sender As System.Object, _ ByVal e As System.EventArgs) Handles Button1.Click Introduction Dim fdlg As OpenFileDialog = New OpenFileDialog() - ADO.NET Basics fdlg.Title = "C# Corner Open File Dialog" Chapter 2 - Data Components in Visual Studio .NET fdlg.InitialDirectory = "c:\\" Chapter 3 - ADO.NET in Disconnected Environments fdlg.Filter = "All files (*.*)|*.mdb|" & _ Chapter 4 - ADO.NET in Connected Environments "MS-Access Database files (*.mdb)|*.mdb" Chapter 5 - Handling ADO.NET Events fdlg.FilterIndex = 2 Chapter 6 fdlg.RestoreDirectory - Integrating XML with ADO.NET = True Chapter 7 If - Data Binding and Windows Forms Data-Bound Controls fdlg.ShowDialog() = DialogResult.OK Then Chapter 8 - Constraints and Data=Relations TextBox1.Text fdlg.FileName Chapter 9 - ADO.NET Handling dbName Exception = fdlg.FileName Chapter 10End - Working If with the ODBC .NET Data Provider Chapter End 11 - Stored Sub Procedures and Views Chapter 1

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

TheGetOleDbSchemaTable method of OleDbConnection returns a DataTable object containing database tables. As you can see from the GetTableBtn_Click handler listed in Listing C-7, we set the Chapter 16 - ASP.NET Server Controls and Data Binding DataSet to the left list box with the DisplayMember property set to TABLE_NAME. We also set Chapter 17 - Building Real-World Web Applications DisplayMember because we show only one column of the DataTable in the list box. Chapter 15 - Using ADO.NET in Xml Web Services


Chapter 19 - C-7: Mapped Objects: PerformanceTables Considerations and Data Binding Listing Getting a Database's from a SQL Server Database Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging

Private Sub GetTables_Click(ByVal sender As System.Object, _ ByVal e As System.EventArgs) Handles GetTables.Click

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B'- Commonly Usedstring SQL Statements Connection

Appendix CDim - ADO.NET Frequently Asked Questions strDSN As String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _ Index "Data Source=" + dbName List of Figures ' Create a connection and open it List of Tables Dim conn As OleDbConnection = New OleDbConnection(strDSN) List of Listings

Try List of Sidebars conn.Open() ' Call GetOleDbSchemaTable to get the schema data table Dim dt As DataTable = _ conn.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, New Object() _ {Nothing, Nothing, Nothing, "TABLE"}) ' Set DataSource and DisplayMember properties ' of the list box control ListBox1.DataSource = dt.DefaultView ListBox1.DisplayMember = "TABLE_NAME" Catch exp As Exception

MessageBox.Show(exp.Message.ToString()) Applied ADO.NET: Building Data-Driven Solutions Finally ISBN:1590590732 by Mahesh and David Talbot ' Close the Chand connection Apress © 2003 (928 pages) conn.Close() This text provides extensive coverage of ADO.NET technology conn.Dispose() including ADO.NET internals, namespaces, classes, and End Try interfaces, and takes a comprehensive look at XML End Sub namespaces and classes, and how to integrate both with ADO.NET.

TableListing of Contents C-8 shows the GetSchemaBn_Click event handler that returns the columns and properties of a Applied ADO.NET—Building Data-Driven Solutions database table. You read the database table using SELECT * and use a DataTable to get columns. The Introduction DataColumn class defines the member for a table column properties such as allow null, auto number, Chapter unique, 1 - column ADO.NETdata Basics type, column name, and so on. Chapter 2


Listing Getting a DatabaseEnvironments Table Schema Chapter 3 - C-8: ADO.NET in Disconnected Chapter 4

- ADO.NET in Connected Environments Private Sub GetTableSchema_Click(ByVal sender As System.Object, _ Chapter 5 - Handling ADO.NET Events

e As System.EventArgs) Handles GetTableSchema.Click Chapter ByVal 6 - Integrating XML with ADO.NET Get Binding the selected item text of list box Chapter 7 '- Data and Windows Forms Data-Bound Controls selTable Chapter 8 Dim - Constraints and As DataString Relations= ListBox1.GetItemText(ListBox1.SelectedItem) Connection string Chapter 9 '- ADO.NET Exception Handling Dim strDSN As String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _ "Data Source=" + dbName 11 - Stored Procedures and Views ' Create and open connection 12 - Oracle, SQLXML, and Other .NET Data Providers Dim conn As OleDbConnection = New OleDbConnection(strDSN) 13 - Developing a Custom Data Provider Try 14 - Developing Database Web Applications using ASP.NET conn.Open() 15 - Using ADO.NET in Web Services Dim strSQL AsXml String = "SELECT * FROM " + selTable 16 - ASP.NET Server Controls and Data Binding ' Create data adapter 17 - Building Real-World Applications Dim adapter AsWeb OleDbDataAdapter = New OleDbDataAdapter(strSQL, conn) 18 - Object-Relational in .NETset ' Create and Mapping fill data 19 - Mapped Objects: Considerations and Data Binding Dim dtSet AsPerformance DataSet = New DataSet() 20 - COM adapter.Fill(dtSet) Interoperability and ADO.NET Dim dt As DataTable = dtSet.Tables(0) 21 - Messaging

Chapter 10 - Working with the ODBC .NET Data Provider Chapter Chapter Chapter Chapter Chapter Chapter Chapter Chapter Chapter Chapter Chapter


' Add items to the box control Appendix A - Relational Databases: Somelist Basic Concepts ListBox2.Items.Add("Column Name, DataType, Unique," & _ Appendix B - Commonly Used SQL Statements " AutoIncrement, Appendix C - ADO.NET Frequently Asked Questions AllowNull") ListBox2.Items.Add("=====================================") Dim i As Integer List of Figures For i = 0 To dt.Columns.Count - 1 List of Tables Dim dc As DataColumn List of Listings dc = dt.Columns(i) List of Sidebars ListBox2.Items.Add(dc.ColumnName.ToString() + _ " , " + dc.DataType.ToString() + _ " ," + dc.Unique.ToString() + " ," + dc.AutoIncrement.ToString() & _ " ," + dc.AllowDBNull.ToString()) Next Index

Catch exp As Exception MessageBox.Show(exp.Message) Finally conn.Close() conn.Dispose() End Try

End Sub Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

This to text provides extensive coverage of ADO.NET select unique rows from a database table technology using SELECT DISTINCT, but somehow this A: It's not a big deal including ADO.NET internals, namespaces, classes, and question gets asked a lot. So, it's not a bad idea to talk about procedure. interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with You can use the SELECT DISTINCT SQL statement to select distinct records from a database. This is ADO.NET.

useful when you want to return only one record corresponding to a criterion. Listing C-9 returns distinct records from the Employees table ordered by the last name. Table of Contents

Listing C-9: Selecting Distinct Rows from a Database Table Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1 - ADO.NET Basics Private Sub DistinctRows_Click(ByVal sender As System.Object, _ Chapter ByVal 2 - Data e Components As System.EventArgs) in Visual Studio .NET Handles DistinctRows.Click

Connection string Environments Chapter 3 '- ADO.NET in Disconnected strDSN As String = "Provider=Microsoft.Jet.OLEDB.4.0;" & _ Chapter 4 Dim - ADO.NET in Connected Environments Source=C:\\Northwind.mdb" Chapter 5 "Data - Handling ADO.NET Events Create aXML connection and open it Chapter 6 '- Integrating with ADO.NET conn As and OleDbConnection = New OleDbConnection(strDSN) Chapter 7 Dim - Data Binding Windows Forms Data-Bound Controls Try - Constraints and Data Relations conn.Open() Chapter 9 - ADO.NET Exception Handling ' Call GetOleDbSchemaTable to get the schema data table Chapter 10 - Working with the ODBC .NET Data Provider Dim sql As String = "SELECT DISTINCT(LastName)" & _ Chapter 11 - Stored Procedures and Views "FROM Employees ORDER BY LastName" Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Dim adapter As OleDbDataAdapter = New OleDbDataAdapter(sql, conn) Chapter 13Dim - Developing Custom Data Provider ds As aDataSet = New DataSet() Chapter 14adapter.Fill(ds, - Developing Database Web Applications "Employees")using ASP.NET Chapter 15DataGrid1.DataSource - Using ADO.NET in Xml Web = Services ds.DefaultViewManager Chapter Catch 16 - ASP.NET Server Controls and exp As Exception Data Binding Chapter 17MessageBox.Show(exp.Message.ToString()) - Building Real-World Web Applications Chapter Finally 18 - Object-Relational Mapping in .NET Close Objects: the connection Chapter 19'- Mapped Performance Considerations and Data Binding Chapter 20conn.Close() - COM Interoperability and ADO.NET Chapter 21conn.Dispose() - Messaging Try Server and ADO.NET: Notes on Performance Chapter End 22 - SQL End ASub Appendix - Relational Databases: Some Basic Concepts Chapter 8

Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index

A: There are many cases when you need to read and store data in the Windows Registry. A common case is storing your program's serial number and activation code in the Windows Registry. The installation package List of Tables of your program writes a serial number and activation code to the Windows Registry, and when the user List of Listings runs program, it checks whether the code matches and runs the program. List of Figures

List of Sidebars

The Windows Registry is a central database for application configuration settings and other information required by the applications. Actually, there's nothing else you can do with the Windows Registry besides reading its data and writing data to it. .NET Framework Library provides two classes (Registry and RegistryKey) to work with the Registry. Note The Registry classes are defined in the Microsoft.Win32 namespace. Before using these classes, you need to add a reference to this namespace. Using the Registry Class TheRegistry class contains members to provides access to Registry keys. Table C-2 described the

Registry class members.


by Registry Mahesh Chand andMembers David Talbot Table C-2: The Class

ISBN:1590590732


MEMBER

DESCRIPTION This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and CurrentUser Stores aboutlook useratpreferences interfaces, and takesinformation a comprehensive XML namespaces and classes, and how to integrate both with LocalMachine Stores configuration information for the local machine ADO.NET. ClassesRoot Table of Contents Users

Stores information about types (and classes) and their properties Stores information about the default user configuration


PerformanceData Introduction

Stores performance information for software components

Chapter 1 - ADO.NET Basics CurrentConfig

Stores non-user-specific hardware information

Chapter 2


DynData Stores dynamic data - ADO.NET in Disconnected Environments

Chapter 3 Chapter 4


For example, if you want to access the HKEY_LOCAL_MACHINE key, you need to call the - Handling ADO.NET Events Registry.LocalMachine member, which returns a RegistryKey type:

Chapter 5 Chapter 6


Chapter 7


RegistryKey pRegKey Registry.LocalMachine; Chapter 8 - Constraints and Data=Relations Chapter 9



Using the RegistryKey Class


The12 RegistryKey classand contains to add, remove, replace, and read Registry data. Table C-3 Chapter - Oracle, SQLXML, Other members .NET Data Providers defines of its acommon properties. Chapter 13 - some Developing Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Table The RegistryKey Class Properties Chapter 15 -C-3: Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

PROPERTY

DESCRIPTION


Name Chapter 18 - Object-Relational Mapping in .NET

Name of the key


SubKeyCount


ValueCount Chapter 21 - Messaging

Number of children of the key Count of values in the key


Table describes the RegistryKey methods. Appendix A C-4 - Relational Databases: Some Basic class Concepts Appendix B - Commonly Used SQL Statements

Table The RegistryKey Class Methods Appendix C -C-4: ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

METHOD


Close

by Mahesh Chand and David Talbot Closes the key Apress © 2003 (928 pages)

ISBN:1590590732

CreateSubKey This text provides Creates extensive a new coverage subkey of if not ADO.NET in existence technology or opens it including ADO.NET internals, namespaces, classes, and

DeleteSubKey subkey interfaces, andDeletes takes a a comprehensive look at XML namespaces and classes, and how to integrate both with

DeleteSubKeyTree ADO.NET.

Deletes subkey and its children

DeleteValue

Deletes the value of a key

Table of Contents GetSubKeyName

Returns an array of strings that contains all the subkey names


GetValue Introduction

Returns the value of a subkey

Chapter 1 - ADO.NET Basics GetValueName

Retrieves an array of strings that contains all the value names associated

Chapter 2

- Data Components inwith Visual Studio .NET a key

Chapter 3


OpenSubKey Opens a subkey - ADO.NET in Connected Environments Chapter 5 - Handling ADO.NET Events SetValue Sets the value of a subkey Chapter 4 Chapter 6


Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Adding a Key and Value to Registry Chapter 8

- Constraints and Data Relations Let's how to add data toHandling the Registry. You use CreateSubKey to add a new key to the Registry and Chapter 9 see - ADO.NET Exception

call the SetValue method to write a value and key. The following code does this:


' Create a new keyand under as MCBInc Chapter 12 - Oracle, SQLXML, Other HKEY_LOCAL_MACHINE\Software .NET Data Providers Dim13key As RegistryKey = Provider Registry.LocalMachine.OpenSubKey("Software", True) Chapter - Developing a Custom Data ' Add one moreDatabase sub key Chapter 14 - Developing Web Applications using ASP.NET Dim newkey As RegistryKey = key.CreateSubKey("MCBInc") ' Set value of sub key Chapter 16 - ASP.NET Server Controls and Data Binding newkey.SetValue("MCBInc", "NET Developer") Chapter 15 - Using ADO.NET in Xml Web Services


Chapter 19 - Mapped Performance Retrieving DataObjects: from the Registry Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Now see how to use these remove the keys and their values from the Registry. Chapter 21let's - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

TheGetValue method returns the value of a subkey in the form of Object. The following code reads the value of the CenteralProcessor\0 subkey and writes it to the console:



' Retrieve data from other part of the registry ' find out your processor List of Figures Dim pRegKey As RegistryKey = Registry.LocalMachine List of Tables pRegKey = List of pRegKey.OpenSubKey("HARDWARE\\DESCRIPTION\\System\\CentralProcessor\\0") Listings List ofDim Sidebars val As Object = pRegKey.GetValue("VendorIdentifier") Console.WriteLine("The central processor of this machine is:" + val) Index

Deleting Data You can use the DeleteValue method to delete the value of a subkey. DeleteSubKey deletes the defined subkey. DeleteSubKey deletes the subkey with its data: Dim delKey As RegistryKey = Registry.LocalMachine.OpenSubKey("Software", True) delKey.DeleteValue("MCBInc") Dim delKey As RegistryKey = Registry.LocalMachine.OpenSubKey("Software", True)

delKey.DeleteSubKey("MCBInc") Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

Apress 2003 (928 Code pages) Examining the Final© Source This text provides extensive coverage of ADO.NET technology

Listing C-10 shows theADO.NET entire source codenamespaces, for reading and writing including internals, classes, andto and from the Windows Registry. interfaces, and takes a comprehensive look at XML andWriting classes,to and how to integrate both with Listing C-10:namespaces Reading and and from the Windows Registry ADO.NET.

Public Sub ReadWriteRegistry() Table of Contents ' Create a new key under HKEY_LOCAL_MACHINE\Software as MCBInc

Dim key As RegistryKey = _ Applied ADO.NET—Building Data-Driven Solutions Registry.LocalMachine.OpenSubKey("Software", True) Introduction Add oneBasics more sub key Chapter 1 '- ADO.NET newkey As RegistryKey = key.CreateSubKey("MCBInc") Chapter 2 Dim - Data Components in Visual Studio .NET Set value of sub key Chapter 3 '- ADO.NET in Disconnected Environments newkey.SetValue("MCBInc", "NET Developer") - ADO.NET in Connected Environments ' Retrieve data from other part of the registry Chapter 5 - Handling ADO.NET Events ' find out your processor Chapter 6 - Integrating XML with ADO.NET Dim pRegKey As RegistryKey = Registry.LocalMachine Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Dim keyPath As String = _ Chapter 8 - Constraints and Data Relations "HARDWARE\\DESCRIPTION\\System\\CentralProcessor\\0" Chapter 9 pRegKey - ADO.NET=Exception Handling pRegKey.OpenSubKey(keyPath) Chapter 10Dim - Working with the ODBC Data Provider val As Object =.NET pRegKey.GetValue("VendorIdentifier") Chapter 11Console.WriteLine("The - Stored Procedures and Views Processor of this machine is:" + val) Chapter 12'- Oracle, and Other .NET Data Providers DeleteSQLXML, the key value Chapter 13Dim - Developing Custom Data Provider= _ delKeya As RegistryKey Chapter 14Registry.LocalMachine.OpenSubKey("Software", - Developing Database Web Applications using ASP.NET True) Chapter 15delKey.DeleteSubKey("MCBInc") - Using ADO.NET in Xml Web Services Sub Chapter End 16 - ASP.NET Server Controls and Data Binding Chapter 4

Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

A: Do 20 you- remember programming ODBC before .NET was introduced? The best way to access databases Chapter COM Interoperability and ADO.NET

through ODBC was to use ODBC Data Source Names (DSNs). You still use ODBC DSNs to access a database by using the ODBC data provider. How do you read all available ODBC DSNs? You do this Chapter 22 - SQL Server and ADO.NET: Notes on Performance through the Windows Registry. All ODBC data sources are stored in the Windows Registry under Appendix A - Relational Databases: Some Basic Concepts LocalMachine\ODBC\ODBC.INI\ODBC Data Sources and Appendix B - Commonly Used SQL Statements CurrentUser\Software\ODBC\ODBC.INI\ODBC Data Sources keys. You use the following code: Chapter 21 - Messaging


Imports Microsoft.Win32


List ofYou Listings just saw how to read and write to the Windows Registry in FAQ 15. Listing C-11 shows the code List ofmodule Sidebars that reads the ODBC system and user DSNs and adds them to a ListBox control.

Listing C-11: Reading ODBC DSNs Private Sub ReadODBCSNs() Dim str As String Dim rootKey As RegistryKey, subKey As RegistryKey Dim dsnList() As String rootKey = Registry.LocalMachine str = "SOFTWARE\\ODBC\\ODBC.INI\\ODBC Data Sources" subKey = rootKey.OpenSubKey(str) dsnList = subKey.GetValueNames()

ListBox1.Items.Add("System DSNs") Applied ADO.NET: Building Data-Driven Solutions ListBox1.Items.Add("================") ISBN:1590590732 by Mahesh and David Talbot Dim dsnName AsChand String Apress © 2003 (928 pages) For Each dsnName In dsnList This text provides extensive coverage of ADO.NET technology ListBox1.Items.Add(dsnName) Next including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML subKey.Close() namespaces and classes, and how to integrate both with rootKey.Close() ADO.NET. ' Load User DSNs rootKey = Registry.CurrentUser Table of Contents str = "SOFTWARE\\ODBC\\ODBC.INI\\ODBC Data Sources" Applied ADO.NET—Building Data-Driven Solutions subKey = rootKey.OpenSubKey(str) Introduction dsnList = subKey.GetValueNames() Chapter 1 ListBox1.Items.Add("================") - ADO.NET Basics Chapter 2 ListBox1.Items.Add("User - Data Components in Visual StudioDSNs") .NET Chapter 3 ListBox1.Items.Add("================") - ADO.NET in Disconnected Environments Each in dsnName dsnList Chapter 4 For - ADO.NET ConnectedIn Environments ListBox1.Items.Add(dsnName) Chapter 5 - Handling ADO.NET Events Chapter 6 Next - Integrating XML with ADO.NET Chapter 7 subKey.Close() - Data Binding and Windows Forms Data-Bound Controls rootKey.Close() Chapter 8 - Constraints and Data Relations End Sub Chapter 9



A: Often you may need to save user images in a database and then read back from a database when needed. For an example, we'll save an author's photo in a database so it can be read later to display in the author's Chapter 14 - Developing Database Web Applications using ASP.NET article. Chapter 13 - Developing a Custom Data Provider


The16Northwind Employees table has a Photo field that stores images of employees. You can Chapter - ASP.NETdatabase's Server Controls and Data Binding use17 this table forReal-World testing your code if you want. For this example, though, we'll create our own database. Chapter - Building Web Applications Chapter 18 - Object-Relational Mapping in .NET

To make it simple, we created a new AppliedAdoNet.mdb Access database and added a Users table to it. The database table schema looks like Figure C-3. Access stores BLOB objects as OLE Object data types.

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars Figure C-3: Users table schema

To make the application a little more interactive and user friendly, we created a Windows application, added aTextBox control, three Button controls, and a PictureBox control. The final form looks like Figure C4. As you can pretty much guess from this figure, the Browse Image button allows users to browse for bitmap files. The Save Image button saves opened file in the database, and the Read Image button reads the first row of the database table, saves binary data as a bitmap, and displays the image in a PictureBox control.


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3

- ADO.NET in Disconnected Environments Figure C-4: Reading and writing images in a database final form

Chapter 4


Chapter 5 -writing Handling ADO.NET Before code on the Events button clicks, define following variables: Chapter 6 - Integrating XML with ADO.NET Chapter 7 - Data Binding variables and Windows Forms Data-Bound Controls ' User defined Chapter Private 8 - Constraints and Data curImage AsRelations Image = Nothing Chapter Private 9 - ADO.NET Exception Handling curFileName As String = Nothing Chapter Private 10 - Working connectionString with the ODBC .NET Data As Provider String = _

" & _ Chapter 11"Provider=Microsoft.Jet.OLEDB.4.0; - Stored Procedures and Views Source=C:\\AppliedAdoNet.mdb" Chapter 12"Data - Oracle, SQLXML, and Other .NET Data Providers savedImageName As String _ Chapter Private 13 - Developing a Custom Data Provider "C:\\ImageFromDb.BMP" Chapter 14=- Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Also, don't forget to add references to the System.IO and System.Data.OleDb namespaces:


Imports System.Data.OleDb Imports System.IO

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 -C-12 SQL shows Server the and Browse ADO.NET: Notesclick on Performance Listing button code, which simply browses bitmap files and saves the filename Appendix in theA curFileName - Relational Databases: variable. Some Basic Concepts Appendix B - Commonly Used SQL Statements

Listing Browse Button Click Event Handler Appendix C - C-12: ADO.NET Frequently Asked Questions Index List ofPrivate Figures Sub BrowseBtn_Click(ByVal sender As System.Object, _ List ofByVal Tables e As System.EventArgs) Handles BrowseBtn.Click

Dim openDlg As OpenFileDialog = New OpenFileDialog() List of Listings openDlg.Filter = "All Bitmap files|*.bmp" List of Sidebars Dim filter As String = openDlg.Filter openDlg.Title = "Open a Bitmap File" If (openDlg.ShowDialog() = DialogResult.OK) Then curFileName = openDlg.FileName TextBox1.Text = curFileName End If End Sub

The Save Image button code shown in Listing C-13 first creates a FileStream object from the bitmap file, opens a connection with the database, adds a new DataRow, set its values, and saves the row back to

database.


Mahesh Chand and David Listing C-13:by Save Image Button Click Talbot Event Handler

ISBN:1590590732

Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology Private Sub SaveImageBtn_Click(ByVal sender As System.Object, _ including ADO.NET internals, namespaces, classes, and ByVal e interfaces, As System.EventArgs) Handles and takes a comprehensive lookSaveImageBtn.Click at XML namespaces and classes, and how to integrate both with ADO.NET. If TextBox1.Text Is String.Empty Then MessageBox.Show("Browse a bitmap") Return Table of Contents End If Applied ADO.NET—Building Data-Driven Solutions ' Read a bitmap contents in a stream Introduction Dim fs As FileStream = New FileStream(curFileName, _ Chapter FileMode.OpenOrCreate, 1 - ADO.NET Basics FileAccess.Read) Chapter 2 Dim - Data ComponentsAs in Visual .NET rawData() ByteStudio = New Byte(fs.Length) {} Chapter 3 fs.Read(rawData, - ADO.NET in Disconnected 0, Environments System.Convert.ToInt32(fs.Length)) Chapter 4 fs.Close() - ADO.NET in Connected Environments Chapter 5 '- Handling ADO.NET Events Construct a SQL string and a connection object Chapter 6 Dim - Integrating sql AsXML String with ADO.NET = "SELECT * FROM Users" conn As and OleDbConnection = New OleDbConnection() Chapter 7 Dim - Data Binding Windows Forms Data-Bound Controls conn.ConnectionString = connectionString Chapter 8 - Constraints and Data Relations Open connection Chapter 9 '- ADO.NET Exception Handling If conn.State ConnectionState.Open Then Chapter 10 - Working with the ODBC .NET Data Provider conn.Open() Chapter 11 - Stored Procedures and Views End If Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers ' Create a data adapter and data set Chapter 13 - Developing a Custom Data Provider Dim adapter As OleDbDataAdapter = _ Chapter 14 - Developing Database Web Applications using ASP.NET New OleDbDataAdapter(sql, conn) Chapter 15 - Using ADO.NET in Xml Web Services Dim cmdBuilder As OleDbCommandBuilder = _ Chapter 16 - ASP.NET Server Controls and Data Binding New OleDbCommandBuilder(adapter) Chapter 17Dim - Building Real-World Web ds As DataSet = Applications New DataSet("Users") Chapter 18adapter.MissingSchemaAction - Object-Relational Mapping in .NET = MissingSchemaAction.AddWithKey Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20'- COM and ADO.NET FillInteroperability data adapter Chapter 21adapter.Fill(ds, - Messaging "Users") Chapter 22 - SQL Server and ADO.NET: Notes on Performance

userDes As String = _ Concepts Appendix ADim - Relational Databases: Some Basic "Mahesh Used Chand a founder of C# Corner " Appendix B - Commonly SQLis Statements "Author: A Programmer's Guide to ADO.NET;" Appendix CuserDes - ADO.NET+= Frequently Asked1. Questions Index

userDes += ", 2. Applied ADO.NET. "

List of Figures

' Create a new row Dim row As DataRow = ds.Tables("Users").NewRow() List of Listings row("UserName") = "Mahesh Chand" List of Sidebars row("UserEmail") = "[email protected]" row("UserDescription") = userDes row("UserPhoto") = rawData ' Add row to the collection ds.Tables("Users").Rows.Add(row) ' Save changes to the database adapter.Update(ds, "Users") ' Clean up connection If conn Is Nothing Then If conn.State = ConnectionState.Open Then conn.Close() End If List of Tables

' Dispose connection Applied ADO.NET: Building Data-Driven Solutions conn.Dispose() ISBN:1590590732 End Ifby Mahesh Chand and David Talbot Apress © 2003 (928 pages) MessageBox.Show("Image Saved") End Sub This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Once data is saved, the next step is to read data from the database table, save it as a bitmap again, and view the bitmap on the form. You can directly view an image using the Graphics.DrawImage method or Tableby of using Contents a PictureBox control. In this case, we'll use a PictureBox.Listing C-14 shows the code for Applied ADO.NET—Building Data-Driven Solutions reading binary data. As you can see, the code simply opens a connection, creates a DataAdapter, fills a Introduction DataSet, and gets the first row of the Users table. Now if you want to read all images, you may want to Chapter modify 1 -your ADO.NET application Basics or make a loop through all rows. Chapter 2


Listing Reading Binary Data Chapter 3 - C-14: ADO.NET in Disconnected Environments Chapter 4

- ADO.NET in Connected Environments Private Sub UseReaderBtn_Click(ByVal sender As System.Object, _ Chapter 5 - Handling ADO.NET Events

ByVal e As System.EventArgs) Chapter 6 - Integrating XML with ADO.NET Handles UseReaderBtn.Click Chapter 7 Chapter Chapter Chapter Chapter Chapter Chapter Chapter


Construct a Data SQLRelations string and a connection object 8 '- Constraints and Dim sql As String = "SELECT UserPhoto FROM Users" 9 - ADO.NET Exception Handling Dim conn As OleDbConnection = New OleDbConnection() 10 - Working with the ODBC .NET Data Provider conn.ConnectionString = connectionString 11 - Stored Procedures and Views ' Open connection 12 - Oracle, SQLXML, and Other .NET Data Providers If conn.State ConnectionState.Open Then 13 - Developing a Custom Data Provider conn.Open() 14 - Developing Database Web Applications using ASP.NET End If

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16Dim - ASP.NET Server Controls and Data Binding cmd As OleDbCommand = New OleDbCommand(sql, conn) Chapter 17Dim - Building Real-World Web Applications fs As FileStream Chapter 18Dim - Object-Relational Mapping in .NET bw As BinaryWriter Chapter 19Dim - Mapped Objects: Performance Considerations bufferSize As Integer = 300000and Data Binding Chapter 20Dim - COM outbyte(300000 Interoperability and-ADO.NET 1) As Byte

retval As Long Chapter 21Dim - Messaging As Long = on 0 Performance Chapter 22Dim - SQLstartIndex Server and ADO.NET: Notes pub_id As String "" Concepts Appendix ADim - Relational Databases: Some=Basic readerUsed As SQL OleDbDataReader = _ Appendix BDim - Commonly Statements cmd.ExecuteReader(CommandBehavior.SequentialAccess) Appendix C - ADO.NET Frequently Asked Questions Index List of List of List of List of

' Read first record reader.Read() Figures fs = New FileStream(savedImageName, _ Tables FileMode.OpenOrCreate, FileAccess.Write) Listings bw = New BinaryWriter(fs) Sidebars startIndex = 0 retval = reader.GetBytes(0, 0, outbyte, 0, bufferSize) bw.Write(outbyte) bw.Flush() ' Close the output file. bw.Close() fs.Close() reader.Close() ' Display image curImage = Image.FromFile(savedImageName) PictureBox1.Image = curImage PictureBox1.Invalidate()

' Clean up connection Applied ADO.NET: Building Data-Driven Solutions If conn.State = ConnectionState.Open Then ISBN:1590590732 by Mahesh Chand and David Talbot conn.Close() Apress © 2003 (928 pages) ' Dispose connection This text provides extensive coverage of ADO.NET technology conn.Dispose() End Ifincluding ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML End Sub namespaces and classes, and how to integrate both with ADO.NET.

TableOnce of Contents a row is read, you get the data stored in the UserPhoto column (Image column) in a stream and save Applied ADO.NET—Building Data-Driven Solutions it as a bitmap file. Later you can view that bitmap file in the PictureBox control by setting its Image Introduction property to the filename. Chapter 1 - ADO.NET Basics

Now, probably want toinsee thisStudio program Chapter 2 you - Data Components Visual .NETin action. You can select any image by clicking the Browse

Image -button, which lets you browse images. Once you've selected a file, you need to save it by clicking the ADO.NET in Disconnected Environments Save Image button. To read the image, simply click the Read Image button. This creates a temporary Chapter 4 - ADO.NET in Connected Environments bitmap file named ImageFromDb.BMP file in c:// folder. You may want to change your path to C:\\. The Chapter 5 - Handling ADO.NET Events final output looks like Figure C-5. Chapter 3

Chapter 6


Chapter 7


Chapter 8


Chapter 9


Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQLC-5: Server and ADO.NET: Notes on reading Performance Figure Displaying a bitmap after data from a database Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

following sections discuss the Questions basics of DiffGrams and how a DataSet utilizes the DiffGram format A: The C Appendix - ADO.NET Frequently Asked Indexin this context. List of Figures

DiffGrams and DataSet

List of Tables

List ofThere Listings are occasions when you want to compare the original data with the current data to get the changes List ofmade Sidebars to the original data. A common example of this is saving data on Web Forms applications. When

working with Web-based data-driven applications, you read data using a DataSet, make some changes to the data, and send data back to the database to save the final data. Sending an entire DataSet may be a costly affair, especially when there are thousands of records in a DataSet. In this scenario, the best practice is to find out the updated rows of a DataSet and send only those rows back to the database instead of the entire DataSet. This is where the DiffGrams are useful. Note Do you remember the GetChanges method of a DataSet? This method returns the rows that have been modified in the current version in the form of a DataSet. This is how a DataSet knows the modified rows. ADiffGram is an XML format used to identify the current and original versions of data elements. Because

theDataSet uses XML to store and transfer data, it also uses DiffGrams to keep track of the original Applieddata. ADO.NET: Data-Driven Solutions data and the current When Building a DataSet is written as a DiffGram, not only does the DiffGram stores ISBN:1590590732 by Mahesh Chand and David Talbot original and current data, it also stores row versions, error information, and their orders. Apress © 2003 (928 pages)

DiffGram XML Format This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

The XML format interfaces, for a DiffGram and takes has a comprehensive three parts: data look instance, at XML DiffGram before, and DiffGram errors. namespacestag and classes, and integratepart both The represents thehow datatoinstance ofwith a DiffGram, which represents the current ADO.NET. data. The DiffGram before is represented by the tag, which represents the original version of the data. The tag represents the DiffGram errors part, which stores the and related information. The DiffGram itself is represented by the tag . Tableerrors of Contents Listing C-15 represents the XML skeleton Applied ADO.NET—Building Data-Driven Solutionsof a DiffGram. Introduction

Listing C-15: ADiffGram Format

Chapter 1

- ADO.NET Basics

Chapter 2

- Data Components in Visual Studio .NET Chapter 3 - ADO.NET in Disconnected Environments

Chapter 4

Chapter 7


Chapter 8


Chapter 9 - ADO.NET Exception Handling Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

The sections only store the changed rows, and the section only stores the rows that had errors. Each row in a DiffGram is identified with an ID, and these three sections Chapter 21 - Messaging communicate through this ID. For example, if the ID of a row is Id1, and it has been modified and has Chapter 22 - SQL Server and ADO.NET: Notes on Performance errors, the stores those errors. Besides the previously discussed three sections, a Appendix A - Relational Databases: Some Basic Concepts DiffGram uses other elements (see Table C-5). Chapter 20 - COM Interoperability and ADO.NET

Appendix B - Commonly Used SQL Statements Appendix C -C-5: ADO.NET Frequently Elements Asked Questions Table The DiffGram Index List of Figures List of Tables List of Listings List of Sidebars

ELEMENT Applied DESCRIPTION ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot This is the DiffGram ID, which is usually in the format of Apress © 2003 (928 pages)

id

[TableName][RowIdentifier]. For example: . including ADO.NET internals, namespaces, classes, and and takes a comprehensive look at XML parented interfaces, This is the parent row of the current row, which is usually in the format of namespaces and classes, and how to integrate both with [TableName][RowIdentifier]. For example: . This identifies a row in the block as modified. The hasChanges element can have one of the three values: inserted,modified, Applied ADO.NET—Building Data-Driven Solutions or descent. The value inserted means an added row, modifiedmeans a Introduction modified row, and descent means the children of a parent row have been Chapter 1 - ADO.NET Basics modified. hasChanges

Table of Contents

Chapter 2

- Data Components in Visual Studio .NET hasErrors identifies Environments a row in the block with a RowError. The error Chapter 3 - ADO.NET inThis Disconnected Chapter 4

is placed in the block. - ADO.NET inelement Connected Environments

Chapter 5 - Handling ADO.NET Eventsthe text of the RowError for a particular element in the error This contains Chapter 6 - Integrating XML with ADO.NET block. Chapter 7


Chapter 8 -are Constraints Data Relations There two moreand elements a DataSet-generatedDiffGram can have, and these elements are Chapter 9 - ADO.NET Exception Handling is the row order of the original data and identifies the index of a row in RowOrder and Hidden. RowOrder Chapter 10 - Working with the ODBC .NET Data Provider a particular DataTable. Hidden identifies a column as having a ColumnMapping property set to Chapter MappingType.Hidden. 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Listing C-16 reads data from the Employees tables and writes in an XML document in DiffGram format.



Listing C-16: ReadingDiffGrams


Dim connectionString As String = _ "Provider=Microsoft.Jet.OLEDB.4.0; Data Source=c:\\Northwind.mdb" Chapter 18 - Object-Relational Mapping in .NET Dim sql As String = _ Chapter 19 - Mapped Objects: Performance Considerations and Data Binding "SELECT EmployeeID, FirstName, LastName, Title FROM Employees" Chapter 20 - COM Interoperability and ADO.NET Dim conn As OleDbConnection = Nothing Chapter 21 - Messaging Dim ds As DataSet = Nothing Chapter 22'- SQL Serverand and open ADO.NET: Notes on Performance Create connection Appendix Aconn - Relational Databases: Some Basic Concepts = New OleDbConnection(connectionString) Appendix BIf - Commonly Used SQL conn.State Statements ConnectionState.Open Then Appendix C - ADO.NET Frequently Asked Questions conn.Open() Index End If List of Figures ' Create a data adapter Dim adapter As OleDbDataAdapter = New OleDbDataAdapter(sql, conn) List of Tables ' Create and fill a DataSet List of Listings ds = New DataSet("TempDtSet") List of Sidebars adapter.Fill(ds, "DtSet") ' Write XML in DiffGram format ds.WriteXml("DiffGramFile.xml", XmlWriteMode.DiffGram) ' Close connection If conn.State = ConnectionState.Open Then conn.Close() End If MessageBox.Show("Done") Chapter 17 - Building Real-World Web Applications

The output of Listing C-16 looks like Figure C-6.


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4Figure - ADO.NET in Connected Environments C-6: DiffGram format Chapter 5

- Handling ADO.NET Events Now update data, you'llADO.NET see new additions to the XML file with and Chapter 6 if -you Integrating XML with

if any errors occur during the update, the entries will go to the Chapter 7 - Data Bindingtags; and Windows Forms Data-Bound Controls section. Chapter 8 - Constraints and Data Relations Chapter 9


You can use the ReadXml method to read XML documents in DiffGram format. The first parameter of ReadXml is the XML document name, and the second parameter should be XmlReadMode.DiffGram:



'

Create a DataSet Object Dim ds As DataSet = New DataSet() Chapter 14 - Developing Database Web Applications using ASP.NET ' Fill with the data Chapter 15 - Using ADO.NET in Xml Web Services ds.ReadXml("DiffGramFile.xml", XmlReadMode.DiffGram) Chapter 13 - Developing a Custom Data Provider

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter Using 18 -the Object-Relational GetChanges Method Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

TheGetChanges method of DataSet can retrieve the rows that have been modified since the last time DataSet was filled, saved, or updated. The GetChanges method returns a DataSet's objects with Chapter 21 - Messaging modified rows. Chapter 20 - COM Interoperability and ADO.NET


Appendix A - Relational Databases: Some TheGetChanges method can takeBasic eitherConcepts no argument or one argument of type DataRowState. The Appendix B - Commonlyenumeration Used SQL Statements DataRowState defines the DataRow state, which can be used to filter a DataSet based on Appendix the types C - ADO.NET of rows.Frequently Table C-6Asked describes Questions the DataRowState members. Index

C-6: The DataRowState Members List ofTable Figures List of Tables

MEMBER

List of Listings

List of Added Sidebars

DESCRIPTION Add added rows to a DataRowCollection of a DataSet and AcceptChanges has not been called.

Deleted

All the deleted rows.

Detached

Rows were created but not added to the row collection. Either waiting for the addition to or removal from the collection.

Modified

Modified rows and AcceptChanges has not been called.

Unchanged

Unchanged rows since last AcceptChanges was called.

Listing C-17 copies only modified rows of ds to a new DataSet called tmpDtSet.

Listing C-17: Reading Only Modified Rows of a DataSet


ISBN:1590590732

' See if DataSet has or not Apress © 2003 (928changes pages) If Not ds.HasChanges(DataRowState.Modified) Then Exit Sub This text provides extensive coverage of ADO.NET technology Dim tmpDtSet As DataSet including ADO.NET internals, namespaces, classes, and ' GetChanges modified rows only. interfaces, for and takes a comprehensive look at XML namespaces and classes, and how to integrate both with tmpDtSet = ds.GetChanges(DataRowState.Modified) ADO.NET. If tmpDtSet.HasErrors Then MessageBox.Show("DataSet has errors") Exit Sub Table of Contents End If Applied ADO.NET—Building Data-Driven Solutions adapter.Update(tmpDtSet) Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3 you - ADO.NET Disconnected Environments Now can use in the new DataSet to bind it to data-bound controls or send back to the database to store Chapter 4 ADO.NET in Connected Environments results. Chapter 5

- Handling ADO.NET Events the defaultXML ExecuteReader Chapter A: Besides 6 - Integrating with ADO.NET method of SqlCommand or other data provider command objects, an

overloaded of ExecuteReader takes an argument of type CommandBehavior enumeration. The Chapter 7 - Dataform Binding and Windows Forms Data-Bound Controls CommandBehavior enumeration provides a description of the results of the query and its effect on the Chapter 8 - Constraints and Data Relations database. We've used the SchemaOnly and SequentialAccess members of CommandBehavior Chapter 9 - ADO.NET Exception Handling members in the samples discussed FAQ 2. However, the CommandBehavor enumeration has few more Chapter 10 - Working with the ODBC .NET in Data Provider members (see Procedures Table C-7).and Views Chapter 11 - Stored Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Table C-7: The CommandBehavior Enumeration


Chapter 14 - Developing DatabaseDESCRIPTION Web Applications using ASP.NET MEMBER Chapter 15 - Using ADO.NET in Xml Web Services

CloseConnection

TheConnection object associated with the DataReader is closed when the DataReader is closed.


Chapter 18 - Object-Relational Mapping .NET No effects. Hence, calling ExecuteReader with Default Defaultinoption. Chapter 19 - Mapped Objects: Performance CommandBehavior.Default Considerations and Data returns Binding the same result as calling

with no parameters. Chapter 20 - COM InteroperabilityExecuteReader and ADO.NET Chapter 21 - Messaging

Returns column and primary key information. You should use this option when you need to read the information about a table's columns and Appendix A - Relational Databases: Some Basic Concepts primary key. KeyInfo

Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix B - Commonly Used SQL Statements

SchemaOnly column information only. Useful when you want to know a table Appendix C - ADO.NET FrequentlyReturns Asked Questions Index

schema. We used this option in FAQ 2 to read a database table schema.

List of SequentialAccess Figures List of Tables

Used to read rows that contain columns with large binary values. The SequentialAccess option allows the DataReader to read data in a stream. We use this option in Listing C-14, where we read binary data.


SingleResult

Returns a single result set.

SingleRow

Returns a single row.

A: Unlike an ADO recordset, the DataReader doesn't provide any property or method that returns the total number of records fetched through a SELECT statement. There are two common ways to find out the total number of records fetched by a DataReader. First, you can use a SELECT COUNT * statement, which was discussed in FAQ 12. Second, you can loop through all the records and store the value in an increment counter. This method is not recommended when there are thousands of records.

Applied ADO.NET: Building Data-Driven Solutions recordset, the DataReader doesn't support EOF either. If there aren't any records left in a A: Unlike an ADO ISBN:1590590732 bythe Mahesh and Talbot DataReader, ReadChand method ofDavid the DataReader returns false. Apress © 2003 (928 pages)

doesn't provideextensive any property or method to sorttechnology the records. The easiest way to sort A: ADataReader This text provides coverage of ADO.NET DataReaderincluding records ADO.NET is using the internals, ORDERnamespaces, BY clause with classes, the SELECT and statement. The ORDER BY clause interfaces, takes a comprehensive look at XML followed by ASC or DESCand sorts in ascending or descending order, respectively. For example, if you want to namespaces and classes, and how to integrate both with sort records based on the Name column in descending order, you use the following SQL statement: ADO.NET. SELECT * FROM Table ORDER BY NAME DESC Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction A: The following Uniform Resource Locator (URL) lists the connection string for different data providers: www.able-consulting.com/ado_conn.htm. Chapter 1 - ADO.NET Basics Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Summary


ISBN:1590590732

In this appendix, we discussed some of the ADO.NET frequently asked questions. There could be a neverApress © 2003 (928 pages) ending list of FAQs related to ADO.NET. We've tried to almost every aspect of ADO.NET This text provides extensive coverage of cover ADO.NET technology programming, butincluding if you don't find the answer to your question in this book, you can go to the FAQ section ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive lookare at XML of C# Corner (www.c-sharpcorner.com) where there hundreds of FAQs. namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Index Numbers


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and 1NF (First Normal Form), 780–782 interfaces, and takes a comprehensive look at XML namespaces classes, and how to integrate both with 2NF (Second Normal Form), and 782–784 ADO.NET.

3NF (Third Normal Form), 784–785 4NF (Fourth Normal Form), 785 Table of Contents

5NF (Fifth Normal Form), 786


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Index A


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and aborted transactions, 747 interfaces, and takes a comprehensive look at XML namespaces and classes, and how integrate both listing), with AcceptChanges and RejectChanges Methods of atoDataSet (code 191-192 ADO.NET.

AcceptChanges method, 127,191-192,231 Access, Microsoft

Tableaccessing of Contents databases, 378-380 Applied ADO.NET—Building exporting table to text Data-Driven file, 383-385Solutions Introduction

Active Data Objects .NET (ADO.NET). SeeADO.NET

Chapter 1

- ADO.NET Basics

ActiveX Data Objects Multi-Dimensional Library (ADOMD), 718 Chapter 2 - Data Components in Visual Studio .NET Add Button Click Event Handler (code listing), 505 Chapter 3 - ADO.NET in Disconnected Environments Chapter 4 Reference - ADO.NET in Connected Add Web feature, 525 Environments Chapter 5 - Handling ADO.NET Events

AddCat1Stored Procedure (code listing), 404

Chapter 6


Chapter 7


AddHandler statement, 209

adding 8data (ASP.NET), 505 Chapter - Constraints and Data Relations Chapter 9 method - ADO.NET Exception130 Handling AddNew (DataView), Chapter 10 Working with the ODBC .NET Data Provider AddRowBtn_Click Method (code listing), 109-110 Chapter 11 - Stored Procedures and Views

administration queues (user), 726


ADO (ActiveX Data Objects) Chapter 13 - Developing a Custom Data Provider comparing with ADO.NET, 11-13 Chapter 14 - Developing Database Web Applications using ASP.NET connections and disconnected data, 11-12 RecordSets vs. DataSets, 12 Chapter 16 - ASP.NET Server Controls and Data Binding XML support, 12-13 Chapter 17 - Building Real-World Web Applications overview of, 6 Chapter 18 - Object-Relational Mapping in .NET recordset and ADO.NET, 712-716 Chapter 15 - Using ADO.NET in Xml Web Services


ADO Examples and Best Practices for Programmers ,760


ADODB Chapter 21Namespace - Messagingto Access a Database (code listing), 715-716 Chapter 22 - SQL Server and ADO.NET: Notes on Performance ADO.NET Appendix A - Relational Databases: Some Basic ADO.NET Application (code listing), 27 Concepts Appendix ADO.NET B - Commonly (Apress),Used 760 SQL Statements

ADOX, with,Frequently 716-718 Asked Questions Appendix C -using ADO.NET Indexarchitecture,75-76

COM interoperability and. SeeCOM interoperability List of Figures creating List of Tables a project, 33 exception List of Listings handling in. Seeexception handling in ADO.NET

Frequently Asked Questions. SeeFrequently Asked Questions, ADO.NET object-relational (OR) mapping in. Seeobject-relational (OR) mapping in .NET overview of, 6-7 SQL Server performance and. SeeSQL Server and ADO.NET using in XML Web services. SeeXML Web services Web application, creating, 478-480 XML, using with, 262-272 displaying XML data in DataSet format, 270 reading XML using DataSet, 262-264 saving data from DataSet to XML, 271-272 writing XML using DataSet, 264-267 XmlDataDocument and DataSet objects, 272 XmlDataDocument and XML, 267-269

List of Sidebars

ADO.NET basics, 1-31 Applied ADO.NET: Building Data-Driven Solutions advantages of, 9-11 ISBN:1590590732 by Mahesh Chand and David Talbot managed code, 10 Apress © 2003 (928 pages) performance and scalability, 11 This text provides extensive coverage of ADO.NET technology single object-oriented API, 9-10 including ADO.NET internals, namespaces, classes, and visual datainterfaces, components, 11 and takes a comprehensive look at XML XML support, 10 namespaces and classes, and how to integrate both with code listings ADO.NET. ADO.NET Application, 27 Viewing Data From SQL Server Database, 30-31 Table of Contents comparing with ADO, 11-13 Applied ADO.NET—Building Data-Driven Solutions connections and disconnected data, 11-12 Introduction RecordSets vs. DataSets, 12 Chapter XML 1 - ADO.NET Basics support, 12-13 Chapter 2 - Data of, Components in Visual Studio .NET components 15-22 Chapter Command 3 - ADO.NET in Disconnected Environments object, 17-18 Chapter CommandBuilder, 4 - ADO.NET in Connected 19 Environments object, 16-17 Chapter Connection 5 - Handling ADO.NET Events Chapter data 6 - providers, Integrating15-16 XML with ADO.NET object, Chapter DataAdapter 7 - Data Binding and19-20 Windows Forms Data-Bound Controls DataSet structure, 20-21 Chapter 8 - Constraints and Data Relations in DataViews, Chapter DataSets 9 - ADO.NET Exception 21-22 Handling creating simple ADO.NET application, 26-28 Chapter 10 - Working with the ODBC .NET Data Provider DataSet to read data, 28-31 Chapter 11 - Stored Procedures and Views Microsoft Data Access Technologies, overview Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers ADO,6 Chapter 13 - Developing a Custom Data Provider ADO.NET,6-7 Chapter 14 - Developing Database Web Applications using ASP.NET DAO,4-5 Chapter MFC, 15 - Using ADO.NET in Xml Web Services 5 Chapter ODBC, 16 - ASP.NET Server Controls and Data Binding 2-4 Chapter OLE 17 - DB, Building Real-World Web Applications 5-6 Chapter RDO, 18 - Object-Relational Mapping in .NET 5 Chapter 19 - Mapped Considerations and Data Binding namespaces andObjects: classesPerformance overview, 13-14 Chapter overview, 20 - COM 6-8 Interoperability and ADO.NET reasons for design of, 8-9 Chapter 21 - Messaging writing applications, 22-26 Chapter 22 -ADO.NET SQL Server and ADO.NET: Notes on Performance .NET Databases: providers, 22-23 Appendixchoosing A - Relational Some Basic Concepts or DataAdapter objects, creating, 25 AppendixCommand B - Commonly Used SQL Statements connections, closing, 26 Appendix C - ADO.NET Frequently Asked Questions connections, establishing, 24-25 Index displaying data, 25-26 List of Figures Filling data to DataSet or DataReader object, 25 List of Tables namespace references, adding, 23-24 List of Listings

ADO.NET events, handling, 209-232 List of Sidebars

code listings ColumnChanging and ColumnChanged Event Handlers, Writing, 222-223 Connection Events, Writing Code That Executes, 214-215 DataAdapter FillError Event Handler Code, 217 DataAdapter's Fill and Update Methods, Calling, 219-220 DataView Event Handler Caller, 230-231 DataView OnListChanged Event Handler, 230 InfoMessage and StateChange events, Writing Event Handlers for, 213 MergeFailed Event Handler, Calling, 220-221 NodeChanged Event Handler, 228 NodeInserted Event Handler, 229 NodeRemoved Event Handler, 229

RowChanging and RowChanged Event Handlers, Writing, 224 Applied ADO.NET: Building Data-Driven Solutions RowDeleting and RowDeleted Event Handlers, Writing, 225-226 ISBN:1590590732 by Mahesh Chand and David Talbot RowUpdated Event Handler, 218 Apress © 2003 (928 pages) RowUpdating Event Handler, 218-219 This text provides extensive coverage SqlDataAdapter Event Handler Bodies, 217 of ADO.NET technology including ADO.NET internals, namespaces, classes, and XmlDataDocument Event Handling Example, 227-228 interfaces, and takes a comprehensive look at XML Connection events, 211-215 namespaces and classes, and how to integrate both with DataAdapter events, 215-220 ADO.NET. DataSet events, 220-221 DataTable events, 221-226 TableDataView of Contents and DataViewManager events, 229-231 Applied ADO.NET—Building fundamentals, 209-211Data-Driven Solutions Introduction XmlDataDocument events, 226-229 Chapter 1

- ADO.NET Basics

ADO.NET in connected environments, 135-208 Chapter 2 - Data Components in Visual Studio .NET code listings Chapter AcceptChanges 3 - ADO.NET in and Disconnected Environments RejectChanges methods of a DataSet, Using, 191-192 Chapter Calling 4 - ADO.NET in Connected Environments a DataAdapter's Fill Method, 171 Chapter Connecting 5 - Handling Events to ADO.NET SQL Server and Reading SqlConnection Properties, 144-145 Chapter Connecting 6 - Integrating XML with to SQL ServerADO.NET Using OleDb Data Provider, 144 Chapter Creating 7 - DataTwo Binding and Windows Data-Bound Controls Connections withForms Different Strings, 147-148 Chapter DataAdapter's 8 - Constraints Update and Data Method, Relations Calling, 178 Using, 180-181 Chapter DataColumnMapping, 9 - ADO.NET Exception Handling From SQL Server Database, 162-164 Chapter DataReader 10 - WorkingReads with the ODBC .NET Data Provider Rows, Adding,and Editing, Deleting, 190-191 Chapter DataSet 11 - Stored Procedures Views toand MapOther Northwind Orders Table, 179 Chapter DataTableMapping 12 - Oracle, SQLXML, .NET Data Providers DataTableMapping with Table Option, Using, 179-180 Chapter 13 - Developing a Custom Data Provider DeleteCommand Property of DataAdapter, Setting, 176 Chapter 14 - Developing Database Web Applications using ASP.NET Displaying Customers Table's Data in DataGrid Using SqlDataAdapter, 174-175 Chapter 15 - Using ADO.NET in Xml Web Services Displaying Orders Table Data in DataGrid Using OleDbAdapter, 173-174 Chapter 16 - ASP.NET Server Controls and Data Binding ExecuteScalar Method to Retrieve Single Value, 160 Chapter 17 - Building Real-World Web Applications Executing Batches Using DataReader, 164-165 Chapter 18 - Object-Relational Mapping in .NET Executing Multiple SQL Queries Using SqlTransaction, 207-208 Chapter Fill 19 method - MappedofObjects: Performance Considerations and Data Binding a DataAdapter, Calling, 177 Chapter Filling 20 - COM Interoperability and ADO.NET Data From Multiple Tables, 188-189 Chapter FillSchema 21 - Messaging method of SqlDataAdapter, Using, 172 Chapter INSERT 22 - SQLSQL Server and ADO.NET: Notes on Performance Statement, Adding Records to Table Using, 159 AppendixMerging A - Relational Databases: Some Basic Two DataSet Objects, 189 Concepts AppendixOleDb B - Commonly Database, Used Connecting SQL Statements to, 143 Using to Access an Access Database, 154 AppendixOleDbCommand, C - ADO.NET Frequently Asked Questions Index Optimistic Concurrency, 202-203 Parameter, Creating a, 185-186 List of Figures Pessimistic Concurrency, 204 List of Tables Private Members, 196-197 List of Listings ReleaseObjectPool, Calling, 149 List of Sidebars Removing a Row and Calling Update Method of DataAdapter, 177 Savepoints in Sql Data Provider, Using, 205-206 Saving Only Modified Rows of DataSet, 193 SELECT Statement, Executing Using OleDbDataAdapter, 167-168 SqlCommand Properties, Setting and Getting, 151 SqlCommand to Read Data from Database, 153 SqlCommandBuilder Class, Creating and Using, 183-184 SqlConnection objects, creating, 139-140 SqlDataAdapter Instances, Creating, 167 SqlDataAdapter Properties, Using, 169 SqlParameter, Creating, 177 Stored Procedure, Calling Using SqlCommand, 155

Stored Procedure, Executing and Reading Results of, 156-157 Applied ADO.NET: Building Data-Driven Solutions Stored Procedure Results Output, Adding Subtotal Listing to, 157 ISBN:1590590732 by Mahesh Chand David Talbot Stored Procedure (Sales byand Year) in Northwind Database, 156 Apress © 2003 (928 pages) TableDirect to Read Table, 158 This text extensive coverage of150-160 ADO.NET technology Command objects andprovides executing SQL statements, including ADO.NET internals, namespaces, classes, and calling stored procedures, 155-157 interfaces, and takes a comprehensive look at XML Commandnamespaces methods, additional, 160 and classes, and how to integrate both with CommandADO.NET. properties, 150-151 CommandType enumeration, 154-155 creating Command objects, 151-153 Table of executing Contents Commands, 158-160 Applied ADO.NET—Building Data-Driven OleDbCommand, creating andSolutions using, 153-154 Introduction TableDirect,157-158 Chapter 1 - ADO.NET Basics CommandBuilder object Chapter creating, 2 - Data Components in Visual Studio .NET 182 Chapter SqlCommandBuilder 3 - ADO.NET in Disconnected members, Environments 182 using,Environments 182-184 Chapter SqlCommandBuilder, 4 - ADO.NET in Connected connecting to dataADO.NET sources,Events 139-150 Chapter 5 - Handling pooling, Chapter connection 6 - Integrating XML145-149 with ADO.NET properties and methods, Chapter Connection 7 - Data Binding and Windows Forms 140-141 Data-Bound Controls CreateCommand and ChangeDatabase methods, 149-150 Chapter 8 - Constraints and Data Relations creating connections, 139-140 Chapter 9 - ADO.NET Exception Handling opening and closing connections, 142-145 Chapter 10 - Working with the ODBC .NET Data Provider DataAdapter,166-181 Chapter 11 - Stored Procedures and Views adding DataTable to DataSet, 172 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers constructing DataAdapter objects, 166-168 Chapter 13 - Developing a Custom Data Provider DataAdapter example, 172-175 Chapter Filling 14 - Developing Database Web Applications using ASP.NET DataAdapter from RecordSet, 175-176 Chapter Filling 15 - Using ADO.NET in Xml Web Services DataSets, 170-171 Chapter methods, 16 - ASP.NET 170 Server Controls and Data Binding Chapter properties, 17 - Building Real-World Web Applications 168-169 Chapter table 18 - Object-Relational Mapping in .NET and column mapping, 178-181 Chapter updating 19 - Mapped database Objects: using Performance Update method, Considerations 176-178 and Data Binding DataReader, Chapter 20 - COM 160-166 Interoperability and ADO.NET 160-161 Chapter basics, 21 - Messaging Behaviors, 165-166Notes on Performance Chapter Command 22 - SQL Server and ADO.NET: 161 Databases: Some Basic Concepts Appendixinitializing, A - Relational batches queries, 164-165 Appendixinterpreting B - Commonly Usedof SQL Statements properties and methods, 161-162 Appendix C - ADO.NET Frequently Asked Questions reading with, 162-164 Index DataSet in connected environments, 188-194 List of Figures accepting/rejecting changes through DataSet, 191-192 List of Tables adding, updating, deleting through DataSet, 190-191 List of Listings DataSet vs. DataReader, 193 List of Sidebars fetching data based on wildcard characters, 194 Filling DataSet from multiple tables, 188-189 saving only changed data, 192-193 SQL statement, reading from two or more tables with, 190 DataView in connected environments, 194-208 batches, executing, 206-208 multiple views, creating, 195-197 Rollback, Commit, and Savepoints, 204-206 transactions and concurrency, 198-200 using concurrency, 201-204 using transactions, 200-201 generic data provider model, 135-136

namespaces, importing, 137 Applied ADO.NET: Building Data-Driven Solutions parameters, construction of, 184-187 ISBN:1590590732 by Mahesh Chand 137-139 and David Talbot System.SqlClient namespace, Apress © 2003 (928 pages)

ADO.NET in disconnected environments, 73-133 This text provides extensive coverage of ADO.NET technology architecture,75-76 including ADO.NET internals, namespaces, classes, and basics,73-74 interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with class hierarchy, 76-80 ADO.NET. code listings AddRowBtn_Click Method, 109-110 Class-Level DataTable and DataSet Variables, 107 Table of Contents ColumnMapping Property of DataColumn, Using, 92 Applied ADO.NET—Building Data-Driven Solutions Columns, Creating Using Different DataColumn Constructors, 88-89 Introduction Contains, Find, and Remove Method of DataRowCollection, Using, 116 Chapter 1 - ADO.NET Basics CreateCustomersTable Method, 107-109 Chapter 2 - Data Components in Visual Studio .NET Custom Properties, Adding and Removing, 93 Chapter Customer/Orders 3 - ADO.NET in Disconnected RelationshipEnvironments Example, 102-105 Chapter Data 4 - ADO.NET in Connected Environments Column, Setting as Primary Key, 90 Chapter DataColumn, 5 - Handling Creating ADO.NET and Events Setting Properties, 89-90 Chapter DataRelation, 6 - Integrating XML with ADO.NET Creating Customer/Order Relationship Using, 100 Chapter DataRow's 7 - Data Binding and Windows Controls98 RejectChanges andForms DeleteData-Bound Methods, Calling, Chapter DataTable 8 - Constraints Objects, andAdding Data Relations to a DataSet, 124-125 Saving in XML Documents, 114 Chapter DataTable, 9 - ADO.NET Exception Handling Objects, Creating from Data a DataTable, Chapter DataView 10 - Working with the ODBC .NET Provider 129 110-112 Chapter DeleteRowsBtn_ClickMethod, 11 - Stored Procedures and Views Constructor CreateCustomersTable, Chapter Form's 12 - Oracle, SQLXML,Calling and Other .NET Data Providers CreateOrdersTable, and BindData, 102 ID and Name Data Columns of Customers Table, Creating, 90 Chapter 13 - Developing a Custom Data Provider InsertAt and RemoveAt Methods, Using, 116 Chapter 14 - Developing Database Web Applications using ASP.NET Merging DataRow and DataTable Objects, 127 Chapter 15 - Using ADO.NET in Xml Web Services Merging Two DataSets, 126-127 Chapter 16 - ASP.NET Server Controls and Data Binding Ordinal and MaxLength properties, Using, 94 Chapter 17 - Building Real-World Web Applications Removing Column From a Collection, 117 Chapter 18 - Object-Relational Mapping in .NET Rows, Adding to DataTable Using DataRow, 96-98 Chapter Rows, 19 - Mapped Performance Considerations and Data Binding 119 EditingObjects: Using BeginEdit, CancelEdit, and EndEdit methods, Chapter Rows, 20 - COM Interoperability and ADO.NET Finding in DataView Using Find Method, 131 Chapter Rows 21 - Messaging of DataView, Adding, Updating, and Deleting, 130 Chapter RowState 22 - SQL Server andCalling, ADO.NET: property, 99 Notes on Performance AppendixSearchButtonClick A - Relational Databases: Some Basic Concepts Method, 112-113 AppendixSelect B - Commonly Method, Sorting Used SQL Data Statements Using, 113-114 and Reading Custom Properties AppendixSetting C - ADO.NET Frequently Asked Questionsof a DataSet, 123-124 Index Setting Values of ID, Address, and Name Columns of DataRow, 95 State of a Row, Determining, 118 List of Figures Table, Creating Using DataTable and DataColumn, 91-92 List of Tables data providers, choosing, 80 List of Listings DataSet objects. SeeDataSet objects List of Sidebars DataTables,83-119 AddRowBtn_Click Method, 109-110 Class-Level DataTable and DataSet Variables, 107 CreateCustomersTable Method, 107-109 DataColumnCollection class, 116-117 DataColumns.SeeDataColumns DataRelations,99-100 DataRow states and versions, 117-119 DataRowCollection class, 115-116 DataRows,94-99 DeleteRowsBtn_ClickMethod, 110-112 fundamentals,83-85

properties and methods, 100-105 Applied ADO.NET: Building Data-Driven Solutions Saving DataTable in XML Documents, 114 ISBN:1590590732 by Mahesh Chand and David Talbot SearchButtonClick Method, 112-113 Apress © 2003 (928 pages) Select Method, Sorting Data Using, 113-114 This text provides extensive coverage of ADO.NET technology DataView objects, 128-131 including ADO.NET internals, namespaces, classes, and DataViewManager,132 interfaces, and takes a comprehensive look at XML disconnected namespaces classes, 81-83 and classes, and how to integrate both with ADO.NET. ADOX From Managed Code, Using (code listing), 717-718

ADOX, using with ADO.NET, 716-718 Table of Contents aliases and joins, 806-807 Applied ADO.NET—Building Data-Driven Solutions

AllowNavigation in Action (code listing), 319

Introduction

AllowPaging, PageSize, and AllowSorting Properties (code listing), 501 Chapter 1 - ADO.NET Basics ALTER2TABLE Statement, 353 Studio .NET Chapter - DataSQL Components in Visual Chapter 3 - rows, ADO.NET in Disconnected Environments alternating multiple columns, and grid lines, 568-569 Chapter 4


Chapter 5


AlternatingItemTemplate code, 575

Appending- in an XML Document Fragment (code listing), 254 Integrating XML with ADO.NET

Chapter 6

Apple Data Access Language (DAL), Forms 4 Chapter 7 - Data Binding and Windows Data-Bound Controls Chapter 8 - Constraints and Data Relations applications Chapter 9 - Web. ADO.NET Handling building building SeeException Web applications, Chapter writing 10 -ADO.NET, Working with 22-26 the ODBC .NET Data Provider

.NET providers, Chapter choosing 11 - Stored Procedures and22-23 Views DataAdapter objects, 25 Chapter Command 12 - Oracle,orSQLXML, and Other .NETcreating, Data Providers closing, 26 Data Provider Chapter connections, 13 - Developing a Custom establishing, 24-25 Chapter connections, 14 - Developing Database Web Applications using ASP.NET 25-26 Chapter displaying 15 - Usingdata, ADO.NET in Xml Web Services

Filling data to DataSet or DataReader object, 25 namespace references, adding, 23-24


architecture, ADO.NET, 75-76 Chapter 18 - Object-Relational Mapping in .NET Chapter 19 -for Mapped Objects: and Data Binding ASP.NET database Web Performance applications,Considerations 465-516 Chapter ADO.NET 20 - COM Web Interoperability application, creating, and ADO.NET 478-480

ASP.NET application development, 468-478 Chapter 21 - Messaging Click event handler, writing code on, 477-478 Chapter Button 22 - SQL Server and ADO.NET: Notes on Performance properties, setting, Some 474-475 Appendixcontrol A - Relational Databases: Basic Concepts new application, Appendixcreating B - Commonly Used SQL 469-472 Statements Outline viewer,Asked 475-476 AppendixDocument C - ADO.NET Frequently Questions

Web controls, adding to Web Form, 472-473 code listings List of Figures Add Button Click Event Handler, 505 List of Tables AllowPaging, PageSize, and AllowSorting Properties, 501 List of Listings DataGrid's PageStyle Modes, Setting, 501 List of Sidebars Deleting Data on Delete Button Click, 507 ExecuteSQL Method, 504 FillDataGrid Method, 503 Filling Data from Database to Data-Bound Controls, 478-480 Filling DatSet from DataAdapter, 498-499 First ASP.NET Application, 486-487 Guest Data, Adding to Database, 510 HTML View of asp:DataGrid, 501 My Home Page and View Guest Book Buttons, 514 PageIndexChanged Handler of DataGrid Control, 500 Page_Load Event Handler Code of ViewGuestBook.aspx, 512-513 Setting Image as DataGrid Control's Next and Previous Page Text, 501 Index

Updating Data on Update Button Click, 506 Applied ADO.NET: Building Data-Driven Solutions ViewGuestBook.aspx, opening, 511 ISBN:1590590732 Mahesh Chand and David Talbot data binding inbyASP.NET, 487-507 Apress © 2003 (928 pages) adding data, 505 This text provides extensive coverage of ADO.NET technology data-bound server-side controls, 488-489 including ADO.NET internals, namespaces, classes, and DataGrid and DataList controls. SeeDataGrid and DataList controls in ASP.NET interfaces, and takes a comprehensive look at XML deleting data, 507 namespaces and classes, and how to integrate both with updating data, 506 ADO.NET. Web Forms, adding, editing, deleting in, 502-504 guest book, creating, 507-515 Table of basics, Contents 507-508 Applied ADO.NET—Building Data-Driven Solutions compiling and running, 514-515 Introduction default Web Form: MyGuestBook.aspx, 508-511 Chapter Web 1 - ADO.NET Basics 511-514 Forms, adding, Chapter 2 - Data Components in Visual Studio .NET overview of ASP.NET, 465-468 Chapter server-side 3 - ADO.NET controls, in Disconnected 480-487 Environments server controls, 481 Environments Chapter HTML 4 - ADO.NET in Connected Framework Library and, 483-485 Chapter .NET 5 - Handling ADO.NET Events 483 Chapter user 6 - controls, Integrating XML with ADO.NET 482-483 Chapter validation 7 - Data controls, Binding and Windows Forms Data-Bound Controls Web Forms, adding to, 485-487 Chapter 8 - Constraints and Data Relations Web Forms controls, 485 Chapter 9 - ADO.NET Exception Handling Web server controls, 481-482 Chapter 10 - Working with the ODBC .NET Data Provider

ASP.NET and and dataViews binding, 537-608 Chapter 11 -server Storedcontrols Procedures code Chapter 12listings - Oracle, SQLXML, and Other .NET Data Providers Click Handlers, Writing, 541 Chapter Button 13 - Developing a Custom Data Provider

ButtonColumn Click Event Handler, 592 Calendar Control, Getting Selected Date of, 542 Chapter 15 - Using ADO.NET in Xml Web Services Calendar Control's Properties, setting, 544 Chapter 16 - ASP.NET Server Controls and Data Binding Data Binding in a DataGrid Control, 583-584 Chapter 17 - Building Real-World Web Applications DataGrid Column's Sequence, Rearranging, 588 Chapter 18 - Object-Relational Mapping in .NET DataGrid Control, Sorting in, 606-607 Chapter DataGrid 19 - Mapped Objects: Performance Considerations and Data Binding Control's Style Properties, Setting, 585-586 Chapter DataGrid 20 - COM with Interoperability and ADO.NET Button Columns, 593-594 Chapter DataList 21 - Messaging Control, Data Binding in, 564-566 Chapter DataList 22 - SQLControl's Server and ADO.NET:Setting, Notes on Performance Properties, 568-569 AppendixDataList A - Relational Databases: Some Basic Concepts Control's Styles, Setting, 570-571 AppendixDropDownList B - CommonlyControl, Used SQL Data Statements Binding in, 559-560 DataGrid, 601-604 AppendixEditable C - ADO.NET Frequently Asked Questions Index Editable DataList Control, 578-581 Formatting BoundColumn's Header and Footers, 588-589 List of Figures ListBox Control, Data Binding in, 557-558 List of Tables Repeater Control, Using, 554-555 List of Listings Simple Template, Applying on a Repeater Control, 546-547 List of Sidebars Template Columns in a DataGrid Control, 596-598 Template Columns, Using, 595-596 Templates, Adding to a DataList Control, 549 Templates of a DataList Control, Adding Formatting to, 550-551 TextBox, Button, and Image Controls, Data Binding in, 561-562 Update, Delete, Cancel, and Edit Command Handlers, Adding, 572 Update, Delete, Cancel, and Edit Command Handlers Code, 573 VisibleMonthChanged Event, 545 complex Web Forms controls, data binding in, 562-607 BaseDataList class, 562-563 DataGrid Web server control. SeeDataGrid Web server control DataKeyCollection class, 563 Chapter 14 - Developing Database Web Applications using ASP.NET

DataList Web server control. SeeDataList Web server control ADO.NET: Building Data-Driven Solutions data binding inApplied Web Forms, 537-539 ISBN:1590590732 by Mahesh Chand andbinding David Talbot simple Web Forms controls, data in, 540-562 Apress © 2003 (928 pages) ASP.NET templates, 547-548 This text provides extensive coverage of ADO.NET technology Button control, 540-541 including ADO.NET internals, namespaces, classes, and Calendar control, 542-545 interfaces, and takes a comprehensive look at XML DropDownList control, and 558-560 namespaces classes, and how to integrate both with ListBox control, 556-558 ADO.NET. ListControl class, 555-556 Repeater control, 552-555 Table of templates, Contents Web server control. Seetemplates, Web server control templates Applied ADO.NET—Building Data-Driven Solutions TextBox, Button and Image controls, 560-562 Introduction

ASP.NET server-side controls, 480-487 - ADO.NET Basics adding to Web Forms, 485-487 Chapter 2 - Data Components in Visual Studio .NET HTML server controls, 481 .NET Framework Library and, 483-485 Chapter - ADO.NET user3 controls, 483in Disconnected Environments Chapter 4 ADO.NET Connected Environments validation controls,in482-483 Chapter 5 Handling ADO.NET Web Forms controls, 485 Events Chapter - Integrating XML with ADO.NET Web6 server controls, 481-482 Chapter 1

Chapter 7

Data Binding and Windows Forms Data-Bound Controls ASP.NET -syntax, 486

Chapter 8


Chapter 9


assemblies, defined, 709

atomic 10 values, 780 with the ODBC .NET Data Provider Chapter - Working Chapter 11 -defined, Stored Procedures and Views attributes, 779 Chapter 12 - Oracle, and 492-493, Other .NET Data Providers Auto Format optionSQLXML, (DataGrid), 552 Chapter 13 - Developing a Custom Data Provider

AutoGenerateColumns property, 586-587


AutoIncrement columns, creating, 822Services Chapter 15 - Using ADO.NET in Xml Web Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Index B


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and b-trees indexing method (SQL Server), 756 interfaces, and takes a comprehensive look at XML namespaces Base Class Library (BCL), 76and classes, and how to integrate both with ADO.NET.

base data providers, 37

BaseDataList class (Web Forms), 562-563 Table of Contents

batches executing, 206-208 Introduction Executing Using DataReader (code listing), 164-165 Chapter 1 - ADO.NET Basics of queries, interpreting, 164-165 Applied ADO.NET—Building Data-Driven Solutions

Chapter 2


Chapter 3


behavior of data, controlling with, 637

BFILEs4(Binary Files),in425 Chapter - ADO.NET Connected Environments Chapter 5 - Handling ADO.NET Events bidirectional data binding, 537-538 Chapter 6 - Integrating XML with ADO.NET Binary Data, Reading (code listing), 837-838 Chapter 7


Chapter 8


BindData method, 105

Binding9class, 288-292 Chapter - ADO.NET Exception Handling Binding Using .NET Binding (code listing), 289 Chapter 10 - Multiple Working Controls with the ODBC Data Provider Binding TextBox Using Binding (code listing), 288-289 BindingsCollection class, 289-290 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers constructing Binding object, 288-289 Chapter 13 - Developing a Custom Data Provider setting Binding class members, 290-292 Chapter 11 - Stored Procedures and Views


BindingContext, 296 Chapter 15 - Using ADO.NET in Xml Web Services BindingManagerBase functionality, Chapter 16 - ASP.NET Server Controls293-296 and Data Binding Chapter - Building Real-World Web Applications BindList17controls, 305 Chapter 18 - Object-Relational Mapping in .NET

bitmaps, reading and writing, 833-838


BLOB data, reading and writing, 833-838


BlockedTree table, 692 Chapter 21 - Messaging Chapter - SQL Server ADO.NET: Notes on Performance Borders22property page,and 497-498 Appendix A - Relational Databases: Some Basic Concepts

bound objects

Appendix B - Commonly Used Statements accessing properties of, SQL 678-680 Appendix - ADO.NET Frequently Asked Questions usingClogic with, 680-685 Index

Boyce-Codd Normal Form (BCNF), 780,785

List of Figures

Browse Button Click Event Handler (code listing), 835 List of Tables Building Distributed Applications with Microsoft .NET ,776 List of Listings List of SidebarsEvent Handler for Calling Order Retrieval Web Service (code listing), 528-529 Button-Click

Button Click event handler, writing code on, 477-478 Button Click Event Handlers (code listing), 614-615 Button Click Handlers, Writing (code listing), 541 Button Columns, using with DataGrid control, 591-594 Button Control (Web Forms), 540-541 Button, TextBox, and Image Controls, Data Binding in (code listing), 561-562 ButtonColumn Click Event Handler (code listing), 592

Index C


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and C++ exception handling, 359 interfaces, and takes a comprehensive look at XML namespaces and classes,706-708 and how to integrate both with caching mechanism, near-zero-impact, ADO.NET.

Calendar Control (Web Forms) Getting Selected Date of (code listing), 542 Setting (code listing), 544 TableProperties, of Contents using, 542-545 Applied ADO.NET—Building Data-Driven Solutions

Introduction Calling a DataAdapter's Fill Method (code listing), 171 Chapter 1 - ADO.NET Basics

Calling DataForm1 from Button Click (code listing), 65

Chapter 2


Calling DataForm2 from Button Click (code listing), 66

Chapter 3

- ADO.NET in Disconnected Environments Calling4DataRow's RejectChanges and Delete Methods (code listing), 98 Chapter - ADO.NET in Connected Environments Chapter - Handling ADO.NET Events Calling5RowState property (code listing), 99 Chapter 6 Integrating XML with ADO.NET Cancel All Button Click Event Handler (code listing), 71 Chapter 7 - Data Binding and Windows Forms Data-Bound Controls

Cancel method (SqlCommand), 160

Chapter 8


CancelCommand event handler, 576 Chapter 9 - ADO.NET Exception Handling Chapter candidate 10 -keys, Working 785 with the ODBC .NET Data Provider Chapter - Stored Procedures and Views caption11 properties Chapter 12 - Oracle, SQLXML, and Other .NET Data321 Providers DataGrid's Caption Properties (code listing), Chapter 13 -320-321 Developing a Custom Data Provider setting, Chapter 14 - Developing Database Web Applications using ASP.NET

CaseSensitive property, 122


ChangeDatabase method, 149-150


CHECK17constraints, defined, 346 Chapter - Building Real-World Web Applications Chapter - Object-Relational Mapping in .NET Check 18 In/Check Out component (Video Store Application), 663-665 Chapter 19 Mapped Objects: Performance Considerations and Data Binding child table, 99 Chapter 20 - COM Interoperability and ADO.NET

ChildNodes property, 252


ChildRelations (DataTable), 99-101 Chapter 22 - SQLproperty Server and ADO.NET: Notes on Performance Appendix class hierarchy, A - Relational ADO.NET, Databases: 76-80Some Basic Concepts Appendix B - Commonly Statements Class-Level DataTableUsed and SQL DataSet Variables (code listing), 107 Appendix C - ADO.NET Frequently Asked Questions

Class Wizard, 520

Index

classes and namespaces overview, 13-14 List of Figures Clear method, 125 List of Tables List of Listings clearing DataSets, 125 List of Sidebars

Client Event Handler for Executing Web Service (code listing), 533 cloning DataSets, 125 Close method (XMLWriter), 250 closing document (XML), 245-246 clustered indexes, 756-757 Code-Behind File of TestDataGrid Program (code listing), 676-677 Code-Behind Object of FancyBinding Page (code listing), 682-684 Code-Behind Object of LazyLoading Page (code listing), 697-700 code listings (by chapter)

ADO.NET basics ADO.NET: Building Data-Driven Solutions ADO.NET Applied application, 27 ISBN:1590590732 by Mahesh Chand andDatabase, David Talbot Viewing Data from SQL Server 30-31 Apress © 2003 (928 pages) ADO.NET events, handling, 222-223 This textand provides extensive coverage ADO.NETWriting, technology ColumnChanging ColumnChanged Event of Handlers, 222-223 including ADO.NET internals, namespaces, classes, and Connection Events, Writing Code That Executes, 214-215 interfaces, and takes a comprehensive look at XML DataAdapter FillError Event Handler Code, 217 namespaces and classes, and how to integrate both with DataAdapter's Fill and Update Methods, Calling, 219-220 ADO.NET. DataView Event Handler Caller, 230-231 DataView OnListChanged Event Handler, 230 Table of InfoMessage Contents and StateChange events, Writing Event Handlers for, 213 Applied ADO.NET—Building Solutions MergeFailed EventData-Driven Handler, Calling, 220-221 Introduction NodeChanged Event Handler, 228 Chapter NodeInserted 1 - ADO.NET Event Basics Handler, 229 Chapter NodeRemoved 2 - Data Components in Visual Studio Event Handler, 229 .NET Chapter RowChanging 3 - ADO.NET in and Disconnected RowChanged Environments Event Handlers, Writing, 224 RowDeleted Event Handlers, Writing, 225-226 Chapter RowDeleting 4 - ADO.NETand in Connected Environments Handler, Chapter RowUpdated 5 - Handling Event ADO.NET Events218 Event 218-219 Chapter RowUpdating 6 - Integrating XML Handler, with ADO.NET Handler Forms Bodies, 217 Chapter SqlDataAdapter 7 - Data BindingEvent and Windows Data-Bound Controls XmlDataDocument Event Handling Example, 227-228 Chapter 8 - Constraints and Data Relations ADO.NET in connected environments Chapter 9 - ADO.NET Exception Handling AcceptChanges and RejectChanges methods of a DataSet, Using, 191-192 Chapter 10 - Working with the ODBC .NET Data Provider Adding, Editing, Deleting DataSet Rows, 190-191 Chapter 11 - Stored Procedures and Views Calling a DataAdapter's Fill Method, 171 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Connecting to SQL Server and Reading SqlConnection Properties, 144-145 Chapter 13 - Developing a Custom Data Provider Connecting to SQL Server Using OleDb Data Provider, 144 Chapter Creating 14 - Developing Database Web using ASP.NET Two Connections withApplications Different Strings, 147-148 Chapter DataAdapter's 15 - Using ADO.NET in Xml Web Services Update Method, Calling, 178 Chapter DataColumnMapping, 16 - ASP.NET Server Controls Data Binding Using, and 180-181 Chapter DataReader 17 - Building Reads Real-World Web Applications From SQL Server Database, 162-164 Chapter DataTableMapping 18 - Object-Relational in .NET to Mapping Map Orders Table of Northwind, 179 Chapter DataTableMapping 19 - Mapped Objects: with Performance Table Option, Considerations Using, 179-180 and Data Binding Propertyand of ADO.NET DataAdapter, Setting, 176 Chapter DeleteCommand 20 - COM Interoperability Customers Table's Data in DataGrid Using SqlDataAdapter, 174-175 Chapter Displaying 21 - Messaging Orders Table Data in DataGrid Using OleDbAdapter, 173-174 Chapter Displaying 22 - SQL Server and ADO.NET: Notes on Performance Method to Retrieve Single Value, 160 AppendixExecuteScalar A - Relational Databases: Some Basic Concepts Batches Using AppendixExecuting B - Commonly Used SQL DataReader, Statements 164-165 Executing Multiple SQL Queries Using SqlTransaction, 207-208 Appendix C - ADO.NET Frequently Asked Questions Fill method of a DataAdapter, Calling, 177 Index Filling Data From Multiple Tables, 188-189 List of Figures FillSchema Method of SqlDataAdapter, Using, 172 List of Tables Merging Two DataSet Objects, 189 List of Listings OleDb Database, Connecting to, 143 List of Sidebars OleDbCommand, Using to Access an Access Database, 154 Optimistic Concurrency, 202-203 Parameter, Creating a, 185-186 Pessimistic Concurrency, 204 Private Members, 196-197 ReleaseObjectPool, Calling, 149 Removing a Row and Calling the Update Method of a DataAdapter, 177 Savepoints in Sql Data Provider, Using, 205-206 Saving Only Modified Rows of DataSet, 193 SELECT Statement, Executing Using OleDbDataAdapter, 167-168 SqlCommand Properties, Setting and Getting, 151 SqlCommand to Read Data from Database, 153

SqlCommandBuilder Class, Creating and Using, 183-184 Applied ADO.NET: Building Data-Driven Solutions SqlConnection objects, creating, 139-140 ISBN:1590590732 by Mahesh Chand Creating, and David167 Talbot SqlDataAdapter Instances, Apress © 2003 (928 pages) SqlDataAdapter properties, Using, 169 This text provides SqlParameter, Creating, 177extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Stored Procedure, Calling Using SqlCommand, 155 interfaces, and takes a comprehensive look at XML Stored Procedure, Executing and Reading of, 156-157 namespaces and classes, and how Results to integrate both with Stored Procedure Results Output, Adding Subtotal Listing to, 157 ADO.NET. Stored Procedure (Sales by Year) in Northwind Database, 156 Table, Adding Records to Using INSERT SQL Statement, 159 Table of TableDirect Contents to Read Table, 158 Applied ADO.NET—Building Data-Driven Solutions116 ADO.NET in disconnected environments, Introduction Adding, Updating, and Deleting Rows of DataView, 130 Chapter AddRowBtn_Click 1 - ADO.NET Basics Method, 109-110 Chapter Class-Level 2 - Data Components Visual StudioVariables, .NET DataTableinand DataSet 107 Chapter Column, 3 - ADO.NET Removing in Disconnected From a Collection, Environments 117 Property ofEnvironments DataColumn, Using, 92 Chapter ColumnMapping 4 - ADO.NET in Connected Creating Using Different DataColumn Constructors, 88-89 Chapter Columns, 5 - Handling ADO.NET Events Find, and Method of DataRowCollection, Using, 116 Chapter Contains, 6 - Integrating XMLRemove with ADO.NET Method, 107-109 Chapter CreateCustomersTable 7 - Data Binding and Windows Forms Data-Bound Controls Custom Properties, Adding and Removing, 93 Chapter 8 - Constraints and Data Relations Customer/Orders Relationship Example, 102-105 Chapter 9 - ADO.NET Exception Handling Data Column, Setting as Primary Key, 90 Chapter 10 - Working with the ODBC .NET Data Provider DataColumn, Creating and Setting Properties of, 89-90 Chapter 11 - Stored Procedures and Views DataRelation, Creating Customer/Order Relationship Using, 100 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers DataRow's RejectChanges and Delete Methods, Calling, 98 Chapter 13 - Developing a Custom Data Provider DataSet Custom Properties, Setting and Reading, 123 Chapter DataTable 14 - Developing Database Web using ASP.NET Objects, Adding to aApplications DataSet, 124-125 Chapter DataView 15 - UsingObjects, ADO.NETCreating in Xml Web Services From a DataTable, 129 Chapter DeleteRowsBtn_ClickMethod, 16 - ASP.NET Server Controls and Data Binding 110-112 Chapter Form's 17 - Building Real-World Web Applications Constructor Calling CreateCustomersTable, CreateOrdersTable, and BindData, 101 Chapter ID, 18 Address, - Object-Relational Mapping in .NET and Name Columns of DataRow, Setting Values of, 95 Chapter ID 19and - Mapped NameObjects: Data Columns Performance of Customers Considerations Table,and creating, Data Binding 90 and DataTable Objects, 127 Chapter Merging 20 - COMDataRow Interoperability and ADO.NET Two DataSets, 126-127 Chapter Merging 21 - Messaging and MaxLength properties, Using, 94 Chapter Ordinal 22 - SQL Server and ADO.NET: Notes on Performance Adding to DataTable Using DataRow, 96-98 AppendixRows, A - Relational Databases: Some Basic Concepts Rows, Editing Using BeginEdit, CancelEdit, and EndEdit methods, 119 Appendix B - Commonly Used SQL Statements Rows, Finding in DataView Using Find Method, 131 Appendix C - ADO.NET Frequently Asked Questions RowState property, Calling, 99 Index Saving DataTable in XML Documents, 114 List of Figures SearchButtonClick Method, 112-113 List of Tables Sorting Data Using Select Method, 113-114 List of Listings State of a Row, Determining, 118 List of Sidebars Table, Creating Using DataTable and DataColumn, 91-92 ASP.NET for database Web applications Add Button Click Event Handler, 505 AllowPaging, PageSize, and AllowSorting Properties, 501 DataGrid's PageStyle Modes, Setting, 501 Deleting Data on Delete Button Click, 507 ExecuteSQL Method, 504 FillDataGrid Method, 503 Filling Data from Database to Data-Bound Controls, 478-480 Filling DataSet from DataAdapter, 498-499 First ASP.NET Application, 486-487 Guest Data, Adding to Database, 510

HTML View of asp:DataGrid, 501 Applied ADO.NET: Building Data-Driven Solutions My Home Page and View Guest Book Buttons, 514 by MaheshHandler Chand and David Talbot PageIndexChanged of DataGrid Control, 500 ISBN:1590590732 Apress © 2003 (928 pages) Page_Load Event Handler Code of ViewGuestBook.aspx, 512-513 This as text providesControl's extensiveNext coverage of ADO.NET technology Setting Image DataGrid and Previous Page Text, 501 including ADO.NET internals, namespaces, classes, and Updating Data on Update Button Click, 506 interfaces, and takes a comprehensive look at XML ViewGuestBook.aspx, 511and how to integrate both with namespaces opening, and classes, ASP.NET server controls and data binding ADO.NET. Button Click Handlers, Writing, 541 ButtonColumn Click Event Handler, 592 Table of Calendar Contents Control, Getting Selected Date of, 542 Applied ADO.NET—Building Calendar Control'sData-Driven Properties, Solutions setting, 544 Introduction Data Binding in a DataGrid Control, 583-584 Chapter DataGrid 1 - ADO.NET BasicsSequence, Rearranging, 588 Column's Chapter DataGrid 2 - Data Control's Components in Properties, Visual Studio .NET 585-586 Style Setting, Chapter DataGrid 3 - ADO.NET with Button in Disconnected Columns,Environments 593-594 Control, Data Binding in, 564-566 Chapter DataList 4 - ADO.NET in Connected Environments Control's Properties, Chapter DataList 5 - Handling ADO.NET Events Setting, 568-569 Control's Styles, Settings, 570-571 Chapter DataList 6 - Integrating XML with ADO.NET Control, Data Binding 559-560 Controls Chapter DropDownList 7 - Data Binding and Windows Formsin, Data-Bound Editable DataGrid, 601-604 Chapter 8 - Constraints and Data Relations Editable DataList Control, 578-581 Chapter 9 - ADO.NET Exception Handling Formatting BoundColumn's Header and Footers, 588-589 Chapter 10 - Working with the ODBC .NET Data Provider ListBox Control, Data Binding in, 557-558 Chapter 11 - Stored Procedures and Views Repeater Control, Using, 554-555 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Simple Template, Applying on a Repeater Control, 546-547 Chapter 13 - Developing a Custom Data Provider Sorting in a DataGrid Control, 606-607 Chapter Template 14 - Developing Database Web Applications ASP.NET Columns in a DataGrid Control, using 596-598 Chapter Template 15 - UsingColumns, ADO.NET in Xml Web Services Using, 595-596 Chapter Templates, 16 - ASP.NET ServertoControls andControl, Data Binding Adding a DataList 549 Chapter Templates 17 - Building Real-World Web Applications of a DataList Control, Adding Formatting to, 550-551 Chapter TextBox, 18 - Object-Relational Mapping in .NET Data Binding in, 561-562 Button, and Image Controls, Chapter Update, 19 - Mapped Delete, Objects: Cancel, Performance and Edit Command Considerations Handlers, and Data Adding, Binding 572 Cancel, and Command Handlers Code, 573 Chapter Update, 20 - COMDelete, Interoperability and Edit ADO.NET Event, 545 Chapter VisibleMonthChanged 21 - Messaging COM Model) interoperability Chapter 22(Component - SQL ServerObject and ADO.NET: Notes on Performance Namespace to Access Database, 715-716 AppendixADODB A - Relational Databases: Some aBasic Concepts ADOX from Managed Code, Using, 717-718 Appendix B - Commonly Used SQL Statements Getting All Dimensions of a Cube, 722-723 Appendix C - ADO.NET Frequently Asked Questions Getting Cubes from FoodMart 2000 Database, 721-722 Index Getting Dimension Members, 723-724 List of Figures constraints List of Tables Adding and Removing, 350-351 List of Listings FOREIGN KEY Constraint, Creating, 347-348 List of Sidebars PRIMARY KEY Constraint, Adding to DataTable, 352 Reading All Constraints of a Collection, 352 UNIQUE constraint, Creating, 348-349 UNIQUE Constraints, Adding, 351 data binding and data-bound controls AllowNavigation in Action, 319 Binding Multiple Controls Using Binding, 289 Binding TextBox Using Binding, 288-289 Counting and Removing Binding objects, 290 CreateDataSet Method, 322-323 Custom Recordset, Creating, 337 CustRecordSet.vb, 335-336

DataGridBoolColumn class, Creating, 318 Data-Driven Solutions DataGrid'sApplied CaptionADO.NET: Properties,Building 321 ISBN:1590590732 by Mahesh Chand and David Talbot DataGrid's Color and Font Properties, Using, 320 Apress © 2003 (928 pages) DataGridTableStyle, Creating and Adding, 315 This text provides extensive coverage of ADO.NET technology DataGridTableStyle from CurrencyManager, 316 including ADO.NET internals, namespaces, classes, and DataSource and DataMember Properties of a DataGrid Control, Setting, 307 interfaces, and takes a comprehensive look at XML Exchanging the Buttonand Click Handler, namespaces classes, and329 how to integrate both with FillDataGrid and Form_Load Methods, 328 ADO.NET. FillDataGrid Method, 323-324,341 FillDataSet Method, 305 Table of Form Contents Load Event Handler, 304 Applied ADO.NET—Building Solutions Format and Parse Data-Driven Event Handlers, Adding, 292 Introduction Form's Load Method, 321 Chapter Getting 1 - ADO.NET Basics a DataGrid Column Header Name, 332 Chapter Getting 2 - Data Components in Visual Studio .NET a DataGrid Columns' Style Using DataGridColumnStyle, 330-331 Chapter Getting 3 - ADO.NET CurrentinDataGridColumnStyle, Disconnected Environments 333-334 in Action, 325-326 Environments Chapter HitTest 4 - ADO.NET in Connected and ComboBox Controls, Binding, 305-306 Chapter ListBox 5 - Handling ADO.NET Events Control Event Handler, Adding, 302-303 Chapter ListBox 6 - Integrating XML with ADO.NET and GetDataSet Methods, Chapter LoadData 7 - Data Binding and Windows Forms 298-299 Data-Bound Controls Move Next, Move Previous, Move First, Move Last Button Code, 299 Chapter 8 - Constraints and Data Relations Moving Record Button Click Event Handlers, 337-338 Chapter 9 - ADO.NET Exception Handling Raising ListBox Events, 303 Chapter 10 - Working with the ODBC .NET Data Provider Reading all Bindings of a Form, 290-291 Chapter 11 - Stored Procedures and Views Reading All Controls Participating in Data Binding, 294 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Reading TextBox Control's Binding Properties, 291-292 Chapter 13 - Developing a Custom Data Provider Record Navigation System Variables, 298 Chapter ReshuffleColumns 14 - Developing Database Web Applications using ASP.NET Method, 329-330 Chapter Saving 15 - Using ADO.NET in Xml Web ServicesFrom a DataGrid Control, 343-344 Updated Data in a Data Source Chapter Search 16 - ASP.NET Server Controls and Data Binding Button Click Event Handler, 341-342 Chapter Sorting 17 - Building Real-World Web Applications a DataGrid Control's Columns, 334 Chapter - Object-Relational data18providers, developingMapping customin .NET Chapter Implementation 19 - Mapped Objects: For anPerformance Enumerator, Considerations 442 and Data Binding Object,and 460-462 Chapter PipedDataAdapter 20 - COM Interoperability ADO.NET Object, 450-453 Chapter PipedDataCommand 21 - Messaging Object, 447-449 Chapter PipedDataConnection 22 - SQL Server and ADO.NET: Notes on Performance Test Case, AppendixPipedDataProvider A - Relational Databases: Some463 Basic Concepts PipedDataReader Object, 454-459 Appendix B - Commonly Used SQL Statements data relations Appendix C - ADO.NET Frequently Asked Questions Creating a DataRelation, 355 Index Deleting a Data Relation from the Collection, 358 List of Figures Filling a DataSet from Two Tables, 354 List of Tables Getting DataRelation Properties, 356-357 List of Listings exception handling in ADO.NET List of Sidebars Custom Filter and Error Message, Defining, 364-365 Nested Try...Catch and Multiple Catch Blocks, 363-364 Opening a File, 360 Reading Data from SQL Server, 371-373 Simple Exception Handling Block, 361 Simple Try...Catch Block, 362 SqlError and SqlErrorCollection objects, 373-374 Try...Catch...Finally statement, 362 Frequently Asked Questions, ADO.NET Binary Data, Reading, 837-838 Browse Button Click Event Handler, 835 DiffGram Format, 840-841

DiffGrams, Reading, 841-842 Applied ADO.NET: Building Data-Driven Solutions GetPageData Method, 816 by MaheshTable ChandSchema and David Talbot Getting a Database Using SqlCommand,ISBN:1590590732 811-812 Apress © 2003 (928 pages) Getting a Database's Table Schema, 826-827 This text provides extensive of ADO.NET technology Getting Database's Tables from SQL coverage Server Database, 825-826 including ADO.NET internals, namespaces, classes, and Paging, Implementing in ADO.NET, 817-820 interfaces, and takes a comprehensive look at XML Reading a namespaces Database Schema Programmatically, 825 both with and classes, and how to integrate Reading and Writing to and from Windows Registry, 831 ADO.NET. Reading DataSet Columns and Their Data Types, 814-815 Reading ODBC DSNs, 832-833 Table of Reading ContentsOnly Modified Rows of DataSet, 843 Applied ADO.NET—Building Save Image ButtonData-Driven Click EventSolutions Handler, 835-837 Introduction Selecting Distinct Rows from DataBase Table, 827-828 Chapter Transactions 1 - ADO.NETinBasics OleDb Data Provider, 821 Chapter 2 - Data Components in Visual Studio .NET mapped objects Chapter Adding 3 - ADO.NET Videos() in Array Disconnected to VideoCategory Environments Object, 695-696 of TestDataGrid Program, 676-677 Chapter Code-Behind 4 - ADO.NETFile in Connected Environments of Events FancyBinding Page, 682-684 Chapter Code-Behind 5 - Handling Object ADO.NET Object of LazyLoading Chapter Code-Behind 6 - Integrating XML with ADO.NET Page, 697-700 Procedure, 692-693 Controls Chapter GetBlockedCategory 7 - Data Binding and Stored Windows Forms Data-Bound HTML of FancyBinding Page, 681-682 Chapter 8 - Constraints and Data Relations HTML of TestGridObjects Page, 679-680 Chapter 9 - ADO.NET Exception Handling HTML Page of Lazy Loading Page, 696-697 Chapter 10 - Working with the ODBC .NET Data Provider HTML Side of TestDataGrid Page, 677-678 Chapter 11 - Stored Procedures and Views Incremental Lazy Loading Stored Procedure, 701 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Theoretical Shopping Cart Example, 680-681 Chapter 13 - Developing a Custom Data Provider VideoCategory and Related Objects, 686-691 Chapter VideoCategoryIndexer, 14 - Developing Database Web Applications using ASP.NET 701-703 Chapter VideoCategoryIndexer 15 - Using ADO.NET in Xml Services TestWeb Case, 703-704 Chapter WeakCache 16 - ASP.NETObject, Server Controls and Data Binding 707-708 Chapter 17 - Building Real-World Web Applications messaging Chapter Creating 18 - Object-Relational a Queue, 737Mapping in .NET Chapter Deleting 19 - Mapped a Queue, Objects: 738Performance Considerations and Data Binding Messages, Sending, 751 Chapter Encrypted 20 - COM Interoperability and ADO.NET Queues Based on Chapter Filtering 21 - Messaging Machine andNotes Label,on733-734 Chapter Category, 22 - SQL Server andName, ADO.NET: Performance a Queue's Properties, 738 AppendixGetting A - Relational Databases: Some Basic Concepts Queues,Used Retrieving, 732 AppendixPrivate B - Commonly SQL Statements Public Queues, Retrieving, 732-733 Appendix C - ADO.NET Frequently Asked Questions Receiving Messages from a Queue, 743-744 Index Sending Messages to a Queue, 743 List of Figures Transactional Messages, Sending and Receiving, 749-750 List of Tables object-relational (OR) mapping in .NET List of Listings SelectVideosCheckedOutToUser,665 List of Sidebars User Object in the User Component, 655-656 UserData Object in the User Component, 656-657 UserDataAccess Object in the User Component, 657-659 UserTestCase Object, 660-661 VideoCheckInCheckOut Component, Test Case for, 671-673 VideoCheckInCheckOut Object, 667-670 VideoTape Component, Test Case For, 653-654 VideoTape Object, 645-648 VideoTapeData Object, 643-644 VideoTapeDataAccess Object, 648-652 ODBC .NET data provider Employees.xls, Accessing Using ODBC Data Provider, 390

MySQL Database, Accessing, 382 Applied ADO.NET: Building Data-Driven Solutions Reading Data from Northwind Using ODBC Data Provider, 379-380 ISBN:1590590732 Mahesh Chand388 and David Talbot TextDB.txtby file, Accessing, Apress © 2003 (928 pages) Oracle .NET data provider textOracle provides extensive417-418 coverage of ADO.NET technology ConnectingThis to an Database, including ADO.NET internals, namespaces, classes, and Constructing SQL INSERT, UPDATE, DELETE Queries, 421 interfaces, and takes a comprehensive look at XML ExecuteSqlQuery Method, 420 namespaces and classes, and how to integrate both with FillDataGrid Method, 419-420 ADO.NET. Oracle-Specific DataReader Methods, 423 OracleDataAdapter, Reading/Writing Data Using, 423-424 Table of OracleDataReader, Contents Reading Data Using, 422-423 Applied ADO.NET—Building Data-Driven Solutions SQL Server and ADO.NET Introduction Generic Data Access Class, 771-773 Chapter Generic 1 - ADO.NET Basics Class, Using, 774-775 Data Access Chapter Query 2 - Data Components in Visual StudioNot .NET from SelectVideosCheckedIn, Optimized, 762-763 Chapter SelectVideosCheckedIn 3 - ADO.NET in Disconnected Query, Environments Optimized Version, 763-764 toConnected Execute aEnvironments Database Query, 765 Chapter sp_executesql 4 - ADO.NET in 773-774 Chapter User-Defined 5 - Handling Variables, ADO.NET Events SQLXML and SQL XML .NETADO.NET data providers Chapter 6 - Integrating XML with 429 Chapter SqlXmlAdapter, 7 - Data BindingUsing, and Windows Forms Data-Bound Controls SqlXmlCommand to Execute Commands, 433-435 Chapter 8 - Constraints and Data Relations stored procedures and views Chapter 9 - ADO.NET Exception Handling AddCat1 Stored Procedure, 404 Chapter 10 - Working with the ODBC .NET Data Provider Executing mySP Stored Procedure Using SQL Data Provider, 400-401 Chapter 11 - Stored Procedures and Views Executing Stored Procedure with Output Parameter, 404-405 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Executing Views Programmatically, 410 Chapter 13 - Developing a Custom Data Provider Parameters, Using in Stored Procedure, 402-404 Chapter 14 Studio - Developing Database Web Applications using ASP.NET Visual .NET data components Chapter Added 15 - Using ADO.NET in Xml Services 48-49 Sql Server Provider Web Components, Chapter Calling 16 - ASP.NET Server Controls and Data 65 Binding DataForm1 from Button Click, Chapter Calling 17 - Building Real-World Web Applications DataForm2 from Button Click, 66 Chapter Cancel 18 - Object-Relational in .NET 71 All Button ClickMapping Event Handler, Chapter DataAdapter 19 - Mapped Objects: Connection Performance through TableMapping, Considerations and 49 Data Binding Method Generated by Data Form Wizard, 69 Chapter FillDataSet 20 - COM Interoperability and ADO.NET Load Event Handler, 50-51 Chapter Form's 21 - Messaging and Server Updateand Button Click Event Handlers, 67-68 Chapter Load 22 - SQL ADO.NET: Notes on Performance Generated by Data Form Wizard, 68-69 AppendixLoadDataSet A - RelationalMethod Databases: Some Basic Concepts Methods Generated by Data Form Wizard, 70-71 AppendixUpdateDataSource B - Commonly Usedand SQLUpdateDataSet Statements Web applications, building Button Click Event Handlers, 614-615 Appendix C - ADO.NET Frequently Asked Questions DisplayData.aspx HTML View, 624-627 Index Done Button Click Event Handler, 620,623 List of Figures FillDataGrid and Page_Load Methods, 627,629 List of Tables FillPartialData Method, 628 List of Listings Login Button Click Event Handler Code, 613 List of Sidebars Post Job Button Click Event Handler, 619 Post Resume Button Click Event Handler, 622-623 Post Resume Page, Adding Options to, 621-622 Register.aspx Code, 616 Resumes.aspx HTML View, 630-632 Send Message Click Event Handler, 618 XML integration with ADO.NET Adding a Node with Attributes, 260 Adding Nodes to a Document, 256 Appending in an XML Document Fragment, 254 GetAttribute of a Node, Using, 243-244 Getting Node Information, 240-241

Getting Root Node of Document, 256 Applied ADO.NET: Building Data-Driven Solutions Getting XML Node Information, 240 ISBN:1590590732 by Mahesh Chand David Talbot Inserting XML Fragment intoand Document, 259 Apress © 2003 (928 pages) MoveToContent Method, Using, 243 This text extensive of ADO.NET technology Moving to Root andprovides First Child Nodes coverage Using XPathNavigator, 274-275 including ADO.NET internals, namespaces, classes, and Output of XmlWriterSample.vb Class, 249-250 interfaces, and takes a comprehensive look at XML Reading an XML file, 239 namespaces and classes, and how to integrate both with RemoveAllADO.NET. for books.xml, Calling, 258 Removing All Items of a Node, 257 ReplaceChild, Calling, 258 Table of Saving Contents DataSet Data to XML Document, 271-272 Applied ADO.NET—Building Data-Driven Solutions Skip Method, Using, 244 Introduction WriteXml method Output, 266 Chapter WriteXml 1 - ADO.NET Basics method, Using, 265-266 Chapter WriteXmlSchema 2 - Data Components in Visual Studio Method, Using, 267 .NET Chapter XML 3 - ADO.NET Schema Generated in Disconnected for Database Environments Table, 284-285 Class, Using, 251 Chapter XmlConvert 4 - ADO.NET in Connected Environments Chapter XmlDataDocumentSample.vb, 5 - Handling ADO.NET Events 270 Chapter XmlDocumentFragment 6 - Integrating XML withSample, ADO.NET254 Example, Chapter XmlWriter 7 - Data Binding and248-249 Windows Forms Data-Bound Controls andand Select, Using, 276-277 Chapter XPathIterator 8 - Constraints Data Relations XPathNavigator, Reading Document Using, 275-276 Chapter 9 - ADO.NET Exception Handling XSL Transformation, 262 Chapter 10 - Working with the ODBC .NET Data Provider XML Web services Chapter 11 - Stored Procedures and Views Button-Click Event Handler for Calling Order Retrieval Web Service, 528-529 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Client Event Handler for Executing Web Service, 533 Chapter 13 - Developing a Custom Data Provider ExecuteQuery Method, 534 Chapter GetOrdersFromDatabase 14 - Developing Database Web Applications using ASP.NET Method, 521 Chapter Populating 15 - Using ADO.NET in Xml Web Services an Order in Database, Web Service Method for, 530-531 Chapter WebService 16 - ASP.NETand Server Controls and Data Binding WebMethod Attributes, Adding Descriptions to, 522-524 Chapter 17 - Building Real-World Web Applications

Color and Font Properties, Using DataGrid's (code listing), 320


columns column and table mapping, 178-181 Chapter 20 - COM Interoperability and ADO.NET ColumnChanged event, 222-223 Chapter 21 - Messaging ColumnChanging and ColumnChanged Event Handlers, Writing (code listing), 222-223 Chapter 22 - SQL Server and ADO.NET: Notes on Performance ColumnMapping property, 92 Appendix A - Relational Databases: Some Basic Concepts ColumnMapping Property of DataColumn, Using (code listing), 92 AppendixColumns B - Commonly Used SQL494-495 Statements property page, AppendixCreating C - ADO.NET Frequently Asked Questions Using Different DataColumn Constructors (code listing), 88-89 Index customizing and rearranging, 587-589 List of Figures defined, 779 List of Tables determinant,785 List of Listings header names, getting, 332 mappings, 45 List of Sidebars selecting for indexing, 757-758 understanding, 586-587 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

COM (Component Object Model) marshaling,12-13 Web services and, 517 COM interoperability, 709-724 .NET Framework interop tools, 710-712 Type Library Exporter (Tlbexp.exe), 712 Type Library Importer (Tlbimp.exe), 711 Visual Studio .NET, 710 ADO recordset and ADO.NET, 712-716

ADOX, using with ADO.NET, 716-718 Applied ADO.NET: Building Data-Driven Solutions basics,709-710 ISBN:1590590732 code listings by Mahesh Chand and David Talbot Apress © 2003 (928 pages) ADODB Namespace to Access a Database, 715-716 This text provides coverage of ADO.NET technology ADOX from Managed Code,extensive Using, 717-718 including ADO.NET internals, namespaces, classes, and Getting All Dimensions of a Cube, 722-723 interfaces, and takes a comprehensive look at XML Getting Cubes from FoodMart 2000and Database, 721-722both with namespaces and classes, how to integrate Getting Dimension ADO.NET.Members, 723-724 COM and .NET Interoperability,709 OLAP server data, accessing, 718-724

Table of Contents

ComboBox and ListBox controls, data binding in, 304-306


Comma Separated Values (CSV) format, 438 Introduction Chapter 1 - Behaviors, ADO.NET Basics Command 165-166 Chapter 2 - components, Data Components Command 75 in Visual Studio .NET Chapter 3


Command objects - ADO.NET in Connected Environments basics,17-18 Chapter 5 - Handling ADO.NET Events creating,25 Chapter 6 - Integrating XML with ADO.NET in custom data provider interfaces, 440-441 Chapter 7 - Datafor Binding anddata Windows Forms Data-Bound Controls vs. DataSet updating sources, 776 Chapter 8 - Constraints and Data Relations properties, 150 Chapter - ADO.NET executing, Exception Handling SQL9 statements, 150-160 Chapter calling 10 - Working the ODBC155-157 .NET Data Provider stored with procedures, Chapter Command 11 - Storedmethods, Procedures and Views 160 Chapter Command 12 - Oracle,properties, SQLXML, and 150-151 Other .NET Data Providers CommandType enumeration, Chapter 13 - Developing a Custom Data154-155 Provider Command objects, 151-153 Chapter creating 14 - Developing Database Web Applications using ASP.NET 158-160 Chapter executing 15 - UsingCommands, ADO.NET in Xml Web Services OleDbCommand, creating and using, Chapter 16 - ASP.NET Server Controls and Data 153-154 Binding TableDirect, 157-158 Chapter 17 - Building Real-World Web Applications Chapter 4

CommandBehavior Chapter 18 - Object-Relational Mapping in .NET enumeration, 843-844 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding understanding, 165-166 Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging CommandBuilder object Chapter creating, 22 - SQL 182 Server and ADO.NET: Notes on Performance

defined, Appendix A - 19 Relational Databases: Some Basic Concepts SqlCommandBuilder members, 182 Appendix B - Commonly Used SQL Statements SqlCommandBuilder, using, Asked 182-184 Appendix C - ADO.NET Frequently Questions Index CommandType enumeration, 154-155 List of Figures Commit, Rollback, and Savepoints, 204-206 List of Tables

committed transactions, 747

List of Listings

complex and simple data binding, 288,538 List of Sidebars complex Web Forms controls, data binding in, 562-607 BaseDataList class, 562-563 DataGrid Web server control. SeeDataGrid Web server control DataKeyCollection class, 563 DataList Web server control. SeeDataList Web server control component isolation, 666-670 components of ADO.NET, 15-22 Command object, 17-18 CommandBuilder, 19 Connection object, 16-17 data providers, 15-16

DataAdapter object, 19-20 Applied ADO.NET: Building Data-Driven Solutions DataSet structure, 20-21 ISBN:1590590732 by Mahesh 21-22 Chand and David Talbot DataSets in DataViews, Apress © 2003 (928 pages)

concurrency This text provides extensive coverage of ADO.NET technology concurrency control, including199 ADO.NET internals, namespaces, classes, and transactions and, 198-200 interfaces, and takes a comprehensive look at XML using,201-204namespaces and classes, and how to integrate both with ADO.NET.

conditional statements in SQL, 799 Configure Data Adapter property, 46-47 Table of Contents

connected environments, ADO.NET in. SeeADO.NET in connected Introduction environments

Applied ADO.NET—Building Data-Driven Solutions Chapter 1

- ADO.NET Basics

connecting to data sources. Seedata sources, connecting to Chapter 2 - Data Components in Visual Studio .NET Connecting to SQL Server and Reading SqlConnection Properties (code listing), 144-145 Chapter 3 - ADO.NET in Disconnected Environments Chapter 4 - ADO.NET in Connected Environments Connecting to SQL Server Using OleDb Data Provider (code listing), 144 Chapter 5 - Handling ADO.NET Events

Connection class members, 141

Chapter 6


Chapter 7


Connection component of DataProvider, 136

Connection events, 211-215 Chapter 8 - Constraints and Data Relations Chapter 9 - ADO.NET Exception Handling Connection Events, Writing Code That Executes (code listing), 214-215 Chapter 10 Working with the ODBC .NET Data Provider Connection objects Chapter 11 - Stored Procedures and Views in custom data provider interfaces, 439-440 Chapter 12 - Oracle, SQLXML, and 16-17 Other .NET Data Providers definition and fundamentals, Chapter 13 - Developing a Custom Data Provider properties, 140 Chapter 14 - Developing Database Web Applications using ASP.NET

connection pooling, 145-149


connection strings for different data providers, 845 Chapter 17 - Building Real-World Web Applications Oracle .NET data provider, 417 Chapter 18 - Object-Relational Mapping in .NET pooling and, 777 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding SqlXmlAdapter object, 428 Chapter 20 - COM Interoperability and ADO.NET understanding, 40 Chapter 16 - ASP.NET Server Controls and Data Binding


connections closing,26,142-145 Appendix A - Relational Databases: Some Basic Concepts Connections, Creating Two with Different Strings (code listing), 147-148 Appendix B - Commonly Used SQL Statements ConnectionState enumeration members, 213 Appendix C - ADO.NET Frequently Asked Questions ConnectionString property, 142 IndexConnectionType enumeration members, 141 List of Figures139-140 creating, List of Tables creating in Oracle .NET data provider, 416-418 List of Listings data, 38-40 List of disconnected Sidebars data and, 11-12 establishing,24-25 opening and closing, 142-145 properties and methods, 140-141 Chapter 22 - SQL Server and ADO.NET: Notes on Performance

constraints adding and removing, 350-351 code listings Adding PRIMARY KEY Constraint to DataTable, 352 Constraints, Adding and Removing, 350-351 FOREIGN KEY Constraint, Creating, 347-348 Reading All Constraints of a Collection, 352 UNIQUE Constraint, Creating, 348-349

UNIQUE Constraints, Adding, 351 Applied ADO.NET: Building Data-Driven Solutions Constraint classes, implementing, 346 ISBN:1590590732 by85 Mahesh Chand and David Talbot constraint rule, Apress © 2003 (928 pages) ConstraintCollection class, 349-350 This text class, provides extensive coverage of ADO.NET technology ForeignKeyConstraint implementing, 346-348 including ADO.NET internals, namespaces, classes, and PRIMARY KEY constraints, adding, 352 interfaces, and takes a comprehensive look at XML property,101 namespaces and classes, and how to integrate both with reading all constraints, ADO.NET. 352 SQL statements to add and remove, 352-353 types of, 345-346 TableUniqueConstraint of Contents class, 348-349 Applied ADO.NET—Building Data-Driven Solutions

Contact.aspx page (Online Job Board Application), 617-618

Introduction

Contains, and Remove Chapter 1 Find, - ADO.NET Basics Method of DataRowCollection, Using (code listing), 116 Chapter content2node, - Data moving Components to (XML), in Visual 242-243 Studio .NET Chapter - ADO.NET in Disconnected Environments Control3and Page classes in data binding, 301,539 Chapter 4


Count (*) to determine number of rows, 823

Chapter 5

- Handling ADO.NET Events Counting Removing Binding Objects (code listing), 290 Chapter 6 and - Integrating XML with ADO.NET

CREATE SQLWindows statement, 393Data-Bound Controls Chapter 7 PROCEDURE - Data Binding and Forms Chapter 8 TABLE - Constraints and Data Relations CREATE SQL statement, 353 Chapter 9 - ADO.NET Exception Handling

CREATE TABLE statements, 803


CREATE VIEW SQL statements, 808-809


CreateCommand ChangeDatabase methods, 149-150 Chapter 12 - Oracle,and SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Method Custom (code Data Provider CreateCustomersTable listing), 107-109 Chapter 14 - Developing Database Web Applications using ASP.NET

CreateDataSet Method (code listing), 322-323


Creating a Queue (code listing), 737


Creating From a DataTable Chapter 17DataView - BuildingObjects Real-World Web Applications(code listing), 129 Chapter Cubes 18 - Object-Relational Mapping in .NET Chapter Getting 19 -All Mapped Dimensions Objects:ofPerformance (code listing), Considerations 722-723 and Data Binding

Getting 2000 and Database (code listing), 721-722 Chapter 20 -from COM FoodMart Interoperability ADO.NET Chapter 21 - object, Messaging CultureInfo 123 Chapter 22 - SQL Server and ADO.NET: Notes on Performance

CurrencyManager DataGridTableStyle From (code listing), 316 Appendix B - Commonly Used295-296 SQL Statements and PropertyManager, Appendix C ADO.NET Frequently Asked for synchronization of controls, 293Questions


Index

cursors locks and, 766 List of Tables and recordsets, 786-787 List of Figures

List of Listings

CustEmpView, 409-410

List of Sidebars

custom controls (server-side), 483 custom data providers, developing. Seedata providers, developing custom custom filters and error messages, 364-365 Custom Properties, Adding and Removing (code listing), 93 Custom Properties of a DataSet, Setting and Reading (code listing), 123-124 Custom Recordset, Creating (code listing), 337 Customer/Orders Relationship Example (code listing), 102-105 CustRecordSet.vb (code listing), 335-336

Index D


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and DAO (Data Access Objects), 4-5 interfaces, and takes a comprehensive look at XML namespaces and 641, classes, and how to integrate both with Data Access Component (DAC), 648-652, 770-775 ADO.NET.

Data Adapter Configuration Wizard, 41-51 DataAdapter, adding, 42-44 TableDataAdapter of Contents properties, setting and reviewing, 44-46 DataGrid control, adding, 42 Applied ADO.NET—Building Data-Driven Solutions DataGrid control, filling with data, 50-51 Introduction project Chapter 1 -template, ADO.NET 42 Basics reviewing options, 46-48 in Visual Studio .NET Chapter 2 - Data Components source code, 48-49 Chapter 3 - ADO.NET in Disconnected Environments data binding Chapter 4 - ADO.NET in Connected Environments

ASP.NET server controls SeeASP.NET server controls and data binding Chapter 5 - Handling ADO.NETand. Events in ComboBox and ListBox controls, 304-306 Chapter 6 - Integrating XML with ADO.NET in complex Web Forms Chapter 7 - Data Binding andcontrols, Windows562-607 Forms Data-Bound Controls

BaseDataList class, 562-563 - Constraints and Data Relations DataGrid Web server control. SeeDataGrid Web server control Chapter 9 - ADO.NET Exception Handling DataKeyCollection class, 563 Chapter 10 - Working with the ODBC .NET Data Provider DataList Web server control. SeeDataList Web server control Chapter 11 - Stored Procedures and Views Control and Page classes in, 539 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers mapped objects and, 675-684 Chapter bound 13 - Developing a Custom Data Provider objects, accessing properties of, 678-680 Chapter bound 14 - Developing Database Web Applications objects, using logic with, 680-685 using ASP.NET Chapter connection 15 - Using ADO.NET in Xml Web Services strings, 676 Chapter 16 ASP.NET Server Controls and Data Binding read-only,537 Chapter 17 Building Real-World Repeater control and, 553 Web Applications Chapter simple 18 -and Object-Relational complex, 538 Mapping in .NET in simple Web Forms controls, 540-562 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding templates, 547-548 Chapter ASP.NET 20 - COM Interoperability and ADO.NET control, 540-541 Chapter Button 21 - Messaging control,and 542-545 Chapter Calendar 22 - SQL Server ADO.NET: Notes on Performance 558-560 AppendixDropDownList A - Relational control, Databases: Some Basic Concepts ListBox control, 556-558 Appendix B - Commonly Used SQL Statements ListControl class, 555-556 Appendix C - ADO.NET Frequently Asked Questions Repeater control, 552-555 Index templates, Web server control. Seetemplates, Web server control templates List of Figures TextBox, Button and Image controls, 560-562 List of Tables in Web Forms, 537-539 Chapter 8

List of Listings

data binding and data-bound controls, 287-344 code listings AllowNavigation in Action, 319 Binding Multiple Controls Using Binding, 289 Binding TextBox Using Binding, 288-289 Counting and Removing Binding objects, 290 CreateDataSet Method, 322-323 Custom Recordset, Creating, 337 CustRecordSet.vb, 335-336 DataGridBoolColumn Class, Creating, 318 DataGrid's Caption Properties, 321 DataGrid's Color and Font Properties, Using, 320 DataGridTableStyle, Creating and Adding, 315

List of Sidebars

DataGridTableStyle From CurrencyManager, 316 Applied ADO.NET: Building Data-Driven Solutions Exchanging the Button Click Handler, 329 ISBN:1590590732 byand Mahesh Chand and David Talbot FillDataGrid Form_Load Methods, 328 Apress © 2003 (928 pages) FillDataGrid Method, 323-324,341 text provides extensive coverage of ADO.NET technology FillDataSetThis Method, 305 including ADO.NET internals, namespaces, classes, and Form Load Event Handler, 304 interfaces, and takes a comprehensive look at XML Format and Parse Event Adding, 292 namespaces andHandlers, classes, and how to integrate both with Form's Load Method, 321 ADO.NET. Getting a DataGrid Column Header Name, 332 Getting a DataGrid Columns' Style Using DataGridColumnStyle, 330-331 Table of Getting Contents Current DataGridColumnStyle, 333-334 Applied ADO.NET—Building Data-Driven Solutions HitTest in Action, 325-326 Introduction ListBox and ComboBox Controls, Binding, 305-306 Chapter ListBox 1 - ADO.NET ControlBasics Event Handler, Adding, 302-303 Chapter LoadData 2 - Data Components in Visual Studio298-299 .NET and GetDataSet Methods, Chapter Move 3 - ADO.NET Next, Move in Disconnected Previous, Move Environments First, Move Last Button Code, 299 RecordinButton ClickEnvironments Event Handlers, 337-338 Chapter Moving 4 - ADO.NET Connected ListBox Events, Events 303 Chapter Raising 5 - Handling ADO.NET all Bindings of a Form, 290-291 Chapter Reading 6 - Integrating XML with ADO.NET Controls in Data Binding,Controls 294 Chapter Reading 7 - DataAll Binding andParticipating Windows Forms Data-Bound Reading TextBox Control's Binding Properties, 291-292 Chapter 8 - Constraints and Data Relations Record Navigation System Variables, 298 Chapter 9 - ADO.NET Exception Handling ReshuffleColumns Method, 329-330 Chapter 10 - Working with the ODBC .NET Data Provider Saving Updates Data in a Data Source From a DataGrid Control, 343-344 Chapter 11 - Stored Procedures and Views Search Button Click Event Handler, 341-342 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Setting DataSource and DataMember Properties of a DataGrid Control, 307 Chapter 13 - Developing a Custom Data Provider Sorting a DataGrid Control's Columns, 334 Chapter 14 - Developing Applications using ASP.NET complex data-boundDatabase controls,Web 301-307 Chapter ComboBox 15 - Using ADO.NET in Xml Web and ListBox controls,Services data binding in, 304-306 Chapter Control 16 - ASP.NET Server class in data Controls binding, and 301Data Binding Chapter DataGrid 17 - Building Real-World Web Applications control, data binding in, 306-307 Chapter deleting 18 - Object-Relational in .NET data binding, Mapping 307 Chapter ListControl 19 - Mapped class, Objects: 301-302 Performance Considerations and Data Binding DataBinding-related events, 302-303 Chapter ListControl 20 - COM Interoperability and ADO.NET DataGrid control. SeeDataGrid control Chapter 21 - Messaging fundamentals of data binding, 287-301 Chapter 22 - SQL Server and ADO.NET: Notes on Performance class, 288-292 AppendixBinding A - Relational Databases: Some Basic Concepts AppendixBindingContext, B - Commonly 296 Used SQL Statements BindingManagerBase functionality, 293-296 Appendix C - ADO.NET Frequently Asked Questions record navigation system, building, 296-300 Index

Data Binding in a DataGrid Control (code listing), 583-584 List of Figures List of binding Tables in ASP.NET, 487-507 data List of adding Listings data, 505

data-bound List of Sidebars server-side controls, 488-489 DataGrid and DataList controls. SeeDataGrid and DataList controls in ASP.NET deleting data, 507 updating data, 506 Web Forms, adding, editing, and deleting in, 502-504 data-bound connectivity, 193 data-bound controls. See alsodata binding and data-bound controls ASP.NET, 488-489 basics,38 Data Column, Setting as Primary Key (code listing), 90 data components, Visual Studio .NET. SeeVisual Studio .NET data components

data connections, understanding, 38-40


data consumers (OLE DB), 5-6 ISBN:1590590732 by Mahesh Chand and David Talbot Data Form Wizard Apress © 2003 (928 pages) adding items, This 58 text provides extensive coverage of ADO.NET technology calling form from including application, ADO.NET 65-66 internals, namespaces, classes, and and takes a comprehensive look at XML code listings, interfaces, 68-71 namespaces and classes, and how to integrate both with creating relationship between tables, 60-61 ADO.NET. Data Connection, choosing, 59 DataForm1.vb,67-71 choosing, 59 TableDataSet, of Contents display style, choosing, 62-65 Applied ADO.NET—Building Data-Driven Solutions displaying tables and columns, 62 Introduction MyDS.xsd, 67 Chapter 1 - ADO.NET Basics project template, 58 Chapter 2 - Data Components in Visual Studio .NET tables or views, choosing, 59-60 Chapter 3 - ADO.NET in Disconnected Environments viewing output, 66 Chapter 4

- ADO.NET in Connected Environments Data Link Wizard, 35, 40 Chapter 5 Properties - Handling ADO.NET Events

Chapter 6 - (mapped Integratingobjects), XML with641, ADO.NET data object 643-644 Chapter 7 Data Binding and Windows Forms Data-Bound Controls data providers. See alsoOracle .NET data provider; SQLXML and SQL XML .NET Chapter 8 data - Constraints base providers,and 37 Data Relations Chapter 9 - ADO.NET Exception Handling choosing, 80 Chapter 10 - Working with the ODBC .NET Data Provider choosing .NET, 22-23 Chapter 11 - Stored Procedures and Views definition and fundamentals, 15-16 Chapter generic 12 - model, Oracle, 135-136 SQLXML, and Other .NET Data Providers

MySQL and .NET data Chapter 13 - database Developing a Custom Dataprovider, Provider 435 ODBC provider, 414 Chapter 14 -data Developing Database Web Applications using ASP.NET ODBC ODBCin.NET data Services provider Chapter 15 -.NET. UsingSee ADO.NET Xml Web ODP.NET data provider, 414 Chapter 16 - ASP.NET Server Controls and Data Binding OleDb provider, 5-6,414 Chapter 17 -data Building Real-World Web Applications

OraDirect.NET, 413 selecting,769-770 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Web-service-based, 437 Chapter 18 - Object-Relational Mapping in .NET


data providers, developing custom, 437-464 Chapter 21 - Messaging advantages 437-438 Chapter 22 - SQLof, Server and ADO.NET: Notes on Performance building,446-463 PipedDataAdapter object, 460-462 Appendix B - Commonly Used SQL Statements PipedDataCommand object, 449-453 Appendix C - ADO.NET Frequently Asked Questions PipedDataConnection object, 446-449 Index PipedDataProvider application, testing, 462-463 List of Figures PipedDataReader object, 453-459 List of Tables code listings List of Listings Implementation for an Enumerator, 442 List of Sidebars PipedDataAdapter Object, 460-462 PipedDataCommand Object, 450-453 PipedDataConnection Object, 447-449 PipedDataProvider Test Case, 463 PipedDataReader Object, 454-459 debugging,464 interfaces, overview of, 438-445 Adapter objects, 443-445 Command objects, 440-441 Connection objects, 439-440 grouped by function, 438 Reader objects, 441-443 Appendix A - Relational Databases: Some Basic Concepts

data relations, 353-358 code listings Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 Mahesh Chand and David Talbot Creating aby DataRelation, 355 Apress © 2003 (928 pages) Deleting a Data Relation from the Collection, 358 This text provides extensive coverage of ADO.NET technology Filling a DataSet from Two Tables, 354 including ADO.NET internals, namespaces, classes, and Getting DataRelation Properties, 356-357 interfaces, and takes a comprehensive look at XML DataRelation namespaces and DataRelationCollection 354-358both with and classes, and objects, how to integrate fundamentals,ADO.NET. 353-354 data sources connecting to, 139-150 Table of Contents connection pooling, 145-149 Applied ADO.NET—Building Data-Driven Solutions connection properties and methods, 140-141 Introduction CreateCommand and ChangeDatabase methods, 149-150 Chapter 1 - ADO.NET Basics creating connections, 139-140 Chapter 2 - Data Components in Visual Studio .NET opening and closing connections, 142-145 Chapter 3 - ADO.NET in Disconnected Environments updating, 776 Chapter 4


data synchronization, 293-294

Chapter 5

- Handling ADO.NET Events DataAdapter objects. See object Chapter 6 - Integrating XMLalso withPipedDataAdapter ADO.NET

constructing, Chapter 7 - Data166-168 Binding and Windows Forms Data-Bound Controls

DataAdapter Connection through TableMapping (code listing), 49 - Constraints and Data Relations DataAdapter events, 215-220 Chapter 9 - ADO.NET Exception Handling DataAdapter example, 172-175 Chapter 10 - Working with the ODBC .NET Data Provider DataAdapter FillError Event Handler Code (code listing), 217 Chapter 11 - Stored Procedures and Views DataAdapter's Fill and Update Methods, Calling (code listing), 219-220 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers DataAdapter's Update Method, Calling (code listing), 178 Chapter 13 - Developing a Custom Data DataTable, adding to DataSet, 172Provider Chapter 14 Developing Database Web Applications Filling DataAdapter from RecordSet, 175-176 using ASP.NET Chapter 15 Using ADO.NET in Xml Web Services Filling DataSets, 170-171 Chapter 16 - ASP.NET Server Controls and Data Binding fundamentals, 19-20 Chapter 17 Building Real-World Web Applications methods,170 Chapter paging 18 -with, Object-Relational 815-816 Mapping in .NET properties, 168-169 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding reading data using, 423-424 Chapter 20 - and COMwriting Interoperability and ADO.NET relationship to DataSet and DataView objects, 121 Chapter 21 - Messaging SQL22DataAdapters, 40-51 Chapter - SQL Server and ADO.NET: Notes on Performance tableAand column mapping, Appendix - Relational Databases:178-181 Some Basic Concepts updating database using Update method, 176-178 Appendix B - Commonly Used SQL Statements Chapter 8

Database Schema, Getting Using SqlCommand (code listing), 811-812 Appendix C -Table ADO.NET Frequently Asked Questions Index databases List of Figures owners, 395 database List of database Tables Web applications using ASP.NET. SeeASP.NET for database Web applications

Database's List of Listings Tables, Getting from SQL Server Database (code listing), 825-826 defined, 779 List of Sidebars design slippage, dangers of, 768-769 pages, checking size of, 767-768 schemas getting programmatically using DataSet, 824-827 obtaining programmatically, 811 Video Store Application design, 641-643 DataBind method, 539 DataBinder.Eval, 678 DataColumns adding to DataTables, 90-92 class properties, 86

creating,86-89 Applied ADO.NET: Building Data-Driven Solutions Creating and Setting Properties (code listing), 89-90 ISBN:1590590732 by Maheshclass, Chand116-117 and David Talbot DataColumnCollection Apress © 2003 (928 pages) DataColumnCollection object, 115 This text provides extensive coverage of ADO.NET technology DataColumnMapping, Using (code listing), 180-181 including ADO.NET internals, namespaces, classes, and properties,85-86,92-94 interfaces, and takes a comprehensive look at XML setting properties, 89-90 and classes, and how to integrate both with namespaces ADO.NET. DataForm1.vb,67-71

DataGrid and DataList controls in ASP.NET, 490-502 TableAutoFormat, of Contents492-493

Borders property page, 497-498 Solutions Applied ADO.NET—Building Data-Driven Columns property page, 494-495 Introduction DataGrid control properties, 490-492 Chapter 1 - ADO.NET Basics Filling 498-499in Visual Studio .NET Chapter 2 a- DataSet, Data Components

Format- property page, 496-497 ADO.NET in Disconnected Environments Paging in DataGrid control, 499-500 Chapter 4 - ADO.NET in Connected Environments Paging programmatically, enabling, 500-502 Chapter 5 - Handling ADO.NET Events Paging property page, 496 Chapter 6 - Integrating XML with ADO.NET Property Builder, 493-494 Chapter 3

Chapter 7


DataGrid control, 307-344 Chapter 8 - Constraints and Data Relations avoiding plus (+) sign in, 813 Chapter 9 - ADO.NET Exception Handling basics,307-308 Chapter 10 - Working with the ODBC .NET Data Provider building DataGrid record navigation system, 335-338 Chapter 11 - Stored Procedures and Views Button Columns, using with, 591-594 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers class properties and methods, 309-312 Chapter 13 - Developing a Custom Data Provider columns Chapter hiding, 14 - Developing 332-334 Database Web Applications using ASP.NET Chapter reshuffling, 15 - Using ADO.NET 326-331 in Xml Web Services Chapter 16 ASP.NET Controls and Data Binding creating editable, Server 598-604 Chapter 17 Building Real-World Web Applications custom sorting in, 334 Chapter data18binding - Object-Relational in, 306-307 Mapping in .NET DataGrid and DataGrid stylesConsiderations and Data Binding Chapter 19 - Mapped Objects:Column Performance Style,and Getting Using DataGridColumnStyle (code listing), 330-331 Chapter DataGrid 20 - COM Columns' Interoperability ADO.NET Control's Columns, Sorting (code listing), 334 Chapter DataGrid 21 - Messaging Getting Notes Current listing), 333-334 Chapter DataGridColumnStyle, 22 - SQL Server and ADO.NET: on (code Performance and DataGridColumnStyle, AppendixDataGridTableStyle A - Relational Databases: Some Basic Concepts 321-324 DataGridTableStyle and DataGridColumnStyle in action, 321-324 Appendix B - Commonly Used SQL Statements DataGrid Column Header Name, Getting (code listing), 332 and DataGrid Column styles, 313-321 Appendix C - ADO.NET Frequently Asked Questions basics,313 Index caption properties, setting, 320-321 List of Figures coloring and font styles, 320 List of Tables DataGridBoolColumn class, 317-318 List of Listings DataGridBoolColumn Class, Creating (code listing), 318 List of Sidebars DataGridColumnStyle class, 316-317 DataGrid's Caption Properties (code listing), 321 DataGrid's Color and Font Properties, Using (code listing), 320 DataGridStyle, constructing and adding, 315-316 DataGridTableStyle class, 314 DataGridTableStyle, Creating and Adding (code listing), 315 DataGridTableStyle from CurrencyManager (code listing), 316 GridColumnStyles property, 314 GridTableStyleCollection members, 314-315 sorting and Navigation, setting, 318-319 DataGrid control events, calling, 589-590 DataGrid Control's Next and Previous Page Text, Setting Image as (code listing), 501

DataGrid's PageStyle Modes, Setting (code listing), 501 Applied ADO.NET: Building Data-Driven Solutions helper objects, 312-313 ISBN:1590590732 by 324-334 Mahesh Chand and David Talbot HitTest method, Apress © 2003 (928 pages) DataGrid.HitTestInfo class, 324-326 This text provides extensive coverage of ADO.NET technology getting column header name, 332 including ADO.NET internals, namespaces, classes, and hiding DataGrid columns, 332-334 interfaces, and takes a comprehensive look at XML reshufflingnamespaces DataGrid columns, 326-331 and classes, and how to integrate both with inserting, updating, and deleting through DataGrids, 342-344 ADO.NET. rows, determining number in, 815 searching a DataGrid, 338-342 Tablesupporting of Contents templates, 548 Applied ADO.NET—Building Data-Driven Solutions

DataGrid Web server control, 582-607 Button Columns, using with, 591-594 Chapter 1 - ADO.NET Basics calling DataGrid events, 589-590 Chapter 2 - Data Components in Visual Studio .NET columns Chapter customizing 3 - ADO.NET in Disconnected Environments and rearranging, 587-589 Chapter understanding, 4 - ADO.NET in Connected Environments 586-587 Chapter 5 - Handling ADO.NET Events creating programmatically, 582 Chapter 6 - Integrating XML with ADO.NET DataGrid Control's Style Properties, Setting (code listing), 585-586 Chapter 7 Data Binding and Windows Forms Data-Bound DataGrid with Button Columns (code listing), 593-594Controls Chapter DataGridColumn 8 - Constraints class, and Data using,Relations 587 DataGridCommandEventArgs class, 591 Chapter 9 - ADO.NET Exception Handling editable DataGrid, creating, 598-604 Chapter 10 - Working with the ODBC .NET Data Provider sorting searching in, 605-607 Chapter 11 -and Stored Procedures and Views styles, Chapter 12 setting, - Oracle,584-586 SQLXML, and Other .NET Data Providers Template Columns, with, 594-598 Chapter 13 - Developing ausing Custom Data Provider Introduction

DataKeyCollection class (Web Forms), 563 Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15Web - Using ADO.NET in 564-582 Xml Web Services DataList server control, Chapter - ASP.NET Server Controls and Data Binding Data16Binding in (code listing), 564-566 Chapter 17 - Building DataKeys, 571 Real-World Web Applications Chapter DataList 18 - Object-Relational Control's Properties, Mapping Setting in .NET (code listing), 568-569

DataList Control's Styles,Performance Settings (code listing), 570-571 Chapter 19 - Mapped Objects: Considerations and Data Binding DataList events, 571-573 Chapter 20 - COM Interoperability and ADO.NET editing, Chapter 21 -updating, Messagingand deleting through, 573-581 multiple columns, and alternating rows, setting, 568-569 Chapter 22 - SQL Servergrid andlines, ADO.NET: Notes on Performance properties Appendix A - Relational Databases: Some Basic Concepts setting,566-567 setting with VS .NET IDE, 581-582 Appendix C - ADO.NET Frequently Asked Questions setting style and templates of, 569-571 Index supporting templates, 548 Appendix B - Commonly Used SQL Statements

List of Figures

DataReader List of Tables

basics,160-161 Command Behaviors, 165-166 List of Sidebars counting total records in, 844 vs. DataSet, 193 end of file, discovering, 844 Executing Batches Using (code listing), 164-165 initializing,161 interpreting batches of queries, 164-165 introduction to, 75 Oracle-Specific DataReader Methods, Using (code listing), 423 properties and methods, 161-162 reading fast data using, 421-423 reading with, 162-164 Reads Data From SQL Server Database (code listing), 162-164 List of Listings

retrieving data with, 775-776 Applied ADO.NET: Building Data-Driven Solutions sorting records using, 845 by Mahesh Chand and David Talbot

ISBN:1590590732

DataRelations Apress © 2003 (928 pages) DataRelation and DataRelationCollection objects, 354-358 This text provides extensive coverage of ADO.NET technology DataRelation,including CreatingADO.NET a (code listing), 355 internals, namespaces, classes, and DataRelation,interfaces, Creating Customer/Order Relationship Using (code listing), 100 and takes a comprehensive look at XML and classes, how to integrate both with DataRelation namespaces Properties, Getting (codeand listing), 356-357 fundamentals,ADO.NET. 99-100 DataRow class properties and methods, 94-95 Table of Contents DataRow states and versions, 117-119 Applied ADO.NET—Building Data-Driven Solutions

DataRowCollection class, 115-116

Introduction

DataRows Chapter 1 - ADO.NET Basics

DataRowState enumeration, 98-99 - Data Components in Visual Studio .NET DataRowState members, 843 Chapter 3 - ADO.NET in Disconnected Environments DataRowView class, 118 Chapter 4 - ADO.NET in Connected Environments fundamentals,94-99 Chapter 2

Chapter 5

- Handling ADO.NET Events DataSet Chapter 6 objects - Integrating XML with ADO.NET

AcceptChanges method, 127 - Data Binding and Windows Forms Data-Bound Controls basics,121-122 Chapter 8 - Constraints and Data Relations vs. commands, 776 Chapter 9 - ADO.NET Exception Handling in connected environments, 188-194 Chapter 10 - Working with the ODBC .NET Data Provider accepting and rejecting changes through DataSet, 191-192 Chapter 11 - Stored Procedures and Views adding, updating, and deleting through DataSet, 190-191 Chapter vs. 12 DataReader, - Oracle, SQLXML, 193 and Other .NET Data Providers Chapter fetching 13 - Developing a Custom Data Provider data based on wildcard characters, 194 Chapter Filling 14 - Developing Database Webtables, Applications using ASP.NET DataSet from multiple 188-189 Chapter saving 15 - Using Xml 192-193 Web Services onlyADO.NET changedindata, Chapter SQL 16 - statement ASP.NET Server Controls and Data Binding to read data from two or more tables, 190 Chapter copying, 17 - Building cloning,Real-World and clearing, Web125 Applications copying of, 822-823 Chapter 18 - contents Object-Relational Mapping in .NET creating, 122 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding DataSet format, displaying XML in, 270 Chapter 20 - COM Interoperability anddata ADO.NET DataSet Rows, Adding, Editing, Deleting (code listing), 190-191 Chapter 21 - Messaging DataSetName property, 122 Chapter 22 - SQL Server and ADO.NET: Notes on Performance DataSetView properties, 132 Appendix A - Relational Databases: Some Basic Concepts DataTables, adding to, 172 Appendix B - Commonly Used SQL Statements DataTables, attaching to, 124-125 Appendix C - ADO.NET Frequently Asked Questions DataView components and, 51-57 Index typed DataSets in VS .NET, 51-54 List of Figures understanding DataView, 54-57 List of in Tables DataViews, 21-22 List of Listings defined, 8,120 List of Sidebars events, 220-221 Filling, 170-171 Filling from multiple views, 411 fundamentals,121-128 getting changed rows of, 125-126 getting column names and data types from, 814 merging DataRow, DataTable or DataSet, 126-127 vs. object-relational mapping, 638 properties,122-124 to read data, 28-31 reading XML using, 262-264 ReadXml method, 127 Chapter 7

ReadXmlSchema method, 127 Applied ADO.NET: Building Data-Driven Solutions vs. RecordSets, 12 ISBN:1590590732 by method, Mahesh Chand RejectChanges 127 and David Talbot Apress © 2003 (928 pages) retrieving data with, 775-776 text provides extensive coverage of ADO.NET technology saving data toThis XML, 271-272 including ADO.NET internals, namespaces, classes, and structure,20-21 interfaces, and takes a comprehensive look at XML typed and untyped, 51-54,and 127-128 namespaces classes, and how to integrate both with WriteXml method, 127 ADO.NET. WriteXmlSchema method, 127 writing XML using, 264-267 TableXmlDataDocument of Contents and, 272 Applied ADO.NET—Building Data-Driven Solutions

DataSource and DataMember Properties of a DataGrid Control, Setting (code listing), 307

Introduction

DataTables Chapter 1 - ADO.NET Basics adding to, 90-92 Chapter 2 -DataColumns Data Components in Visual Studio .NET

adding -DataSet to, 172 ADO.NET in Disconnected Environments AddRowBtn_Click Method, 109-110 Chapter 4 - ADO.NET in Connected Environments attaching to DataSet objects, 124-125 Chapter 5 - Handling ADO.NET Events Class-Level DataTable and DataSet Variables, 107 Chapter 6 - Integrating XML with ADO.NET class properties and methods, 101 Chapter 7 - Data Binding and Windows Forms Data-Bound Controls columns, hiding, 814 Chapter 8 - Constraints and Data Relations CreateCustomersTable Method, 107-109 Chapter 9 ADO.NET Exception Handling DataTable and DataView, searching using, 339-341 Chapter 10 - Working withAdding the ODBC Data(code Provider DataTable Objects, to a.NET DataSet listing), 124-125 Chapter 11 Stored Procedures and Views DataTableCollection class, 124 Chapter 12 - Oracle, SQLXML, and Other Table .NET Data Providers (code listing), 179 DataTableMapping to Map Orders of Northwind Chapter DataTableMapping 13 - Developing awith Custom TableData Option, Provider Using (code listing), 179-180 DataTable.Rows.Add method, 95 Applications using ASP.NET Chapter 14 - Developing Database Web DeleteRowsBtn_ClickMethod, Chapter 15 - Using ADO.NET in Xml 110-112 Web Services events, Chapter 16 -221-226 ASP.NET Server Controls and Data Binding multiple constraints and, 349 Chapter 17 - Building Real-World Web Applications Saving DataTable in XML Documents, 114 Chapter 18 - Object-Relational Mapping in .NET SearchButtonClick Method, 112-113 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Sorting Data Using Select Method, 113-114 Chapter 20 - COM Interoperability and ADO.NET working with, 83-119 Chapter 21 - Messaging DataColumnCollection class, 116-117 Chapter 22 - SQL Server and ADO.NET: Notes on Performance DataColumns.See DataColumns DataRelations, 99-100 Appendix A - Relational Databases: Some Basic Concepts DataRow states and versions, 117-119 AppendixDataRowCollection B - Commonly Usedclass, SQL Statements 115-116 AppendixDataRows, C - ADO.NET Frequently Asked Questions 94-99 Index fundamentals, 83-85 List of Figures properties and methods, 100-105 Chapter 3

List of Tables

DataViews

List of Listings class properties and methods, 128-129 List of Sidebars in connected environments, 194-208

batches, executing, 206-208 concurrency, using, 201-204 multiple views, creating, 195-197 Rollback, Commit, and Savepoints, 204-206 transactions and concurrency, 198-200 transactions, using, 200-201 DataSets in, 21-22 DataView and DataViewManager events, 229-231 DataView Event Handler Caller (code listing), 230-231 DataView OnListChanged Event Handler (code listing), 230 DataViewManager,132

fundamentals,128-131 ADO.NET: Building Data-Driven Solutions relationship toApplied DataSets and DataAdapters, 121 ISBN:1590590732 by Mahesh Chand and David Talbot understanding, 54-57 Apress © 2003 (928 pages)

DBTools Manager, 381


dead letter queues including (system), ADO.NET 726 internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

deadlocks,791 namespaces and classes, and how to integrate both with ADO.NET. debugging custom data providers, 464 default Web Form (guest book), 508-511 Table of Contents DefaultViewManager property, 123 Applied ADO.NET—Building Data-Driven Solutions

Delete methods DataRow, 96 Chapter 1 - ADO.NET Basics DataView, 130 Introduction Chapter 2


Chapter 3


DELETE statements, 534,802-803

DeleteCommand event handler, 577 Chapter 4 - ADO.NET in Connected Environments Chapter DeleteCommand 5 - Handling Property ADO.NET of DataAdapter, Events Setting (code listing), 176 Chapter 6 - Integrating XML with ADO.NET DeleteRowsBtn_ClickMethod (code listing), 110-112 Chapter 7 - Data Binding and Windows Forms Data-Bound Controls

deleting - Constraints and Data Relations data (ASP.NET), 507 Chapter 9 - ADO.NET Exception Handling data binding, 307 Chapter 10 - Working the listing), ODBC .NET Deleting a Queuewith (code 738 Data Provider Chapter 11 Stored Procedures and Views Deleting Data on Delete Button Click (code listing), 507 Chapter 12 - Oracle, SQLXML,through and Other .NET Data Providers inserting, and updating DataGrids, 342-344 Chapter 13 - Developing a through Custom Data Provider updating, and editing DataList control, 573-581 Chapter 8


denormalization

Chapter 15 - 786 Using ADO.NET in Xml Web Services defined, Chapter 16 - ASP.NET Server Controls and Data Binding of tables, 768 Chapter 17 - Building Real-World Web Applications

dependencies, managing (Video Store Application), 661-662


design 19 tradeoffs, 665-673 Chapter - Mapped Objects: Performance Considerations and Data Binding component isolation, 666-667 component isolation workaround, 667-670 Chapter 21 - Messaging stored procedures, logic in, 665-666 Chapter 22 - SQL Server and ADO.NET: Notes on Performance VideoCheckInCheckOut test case, 670-673 Chapter 20 - COM Interoperability and ADO.NET


designerBvs. manual development mode, 775 Appendix - Commonly Used SQL Statements detail table, loading when master is loaded, 703-704 Appendix C - ADO.NET Frequently Asked Questions Index determinant columns, 785 List of Figures

Determining State of a Row (code listing), 118

List of Tables

DiffGrams Format (code listing), 840-841 List of Sidebars fundamentals,839-843 Reading (code listing), 841-842 List of Listings

Dimension Members, Getting (code listing), 723-724 dirty reads, 788 disconnected classes, 74,81-83 disconnected data components, 51 disconnected environments, ADO.NET in.SeeADO.NET in disconnected environments discovery files (Service1.disco), 527

Discovery Service Protocol, 517


DisplayData.aspxby Mahesh Chand and David Talbot HTML View (code listing), 624-627 Apress © 2003 (928 pages) Online Job Board Application, 623-632

ISBN:1590590732


Displaying Customers including Table's ADO.NET Data internals, in DataGrid namespaces, Using SqlDataAdapter classes, and (code listing), 174-175 interfaces, and takes a comprehensive look at XML

displaying data, 25-26 namespaces and classes, and how to integrate both with Displaying OrdersADO.NET. Table Data in DataGrid Using OleDbAdapter (code listing), 173-174 Dispose method (connections), 143,148 Table Contents DLL of hell, 10 Applied ADO.NET—Building Data-Driven Solutions

dnjHeader.aspx page (Online Job Board Application), 632-633

Introduction

Document-Outline viewer, 475-476 ADO.NET Basics

Chapter 1

documents Chapter 2 - Data Components in Visual Studio .NET adding to, 256 Chapter 3 -nodes ADO.NET in Disconnected Environments closing 245-246 Chapter 4 -XML, ADO.NET in Connected Environments XML5 classes, 234ADO.NET Events Chapter - Handling DOM (Document Object Model) Chapter 6 - Integrating XML with ADO.NET implementation, 251-260 Chapter 7 - Data Binding and Windows Forms Data-Bound Controls attributesand to nodes, 259-260 Chapter adding 8 - Constraints Data Relations documents, 253 Handling Chapter saving 9 - ADO.NET Exception class, Chapter XmlDocument 10 - Working with the 252-253 ODBC .NET Data Provider

XmlDocumentFragment class, 253-254 XmlElement class, 254-259 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers XmlNode class, 252 Chapter 13 - Developing a Custom Data Provider interfaces,237 Chapter 11 - Stored Procedures and Views


Done Button ClickADO.NET Event Handler (codeServices listing), 620,623 Chapter 15 - Using in Xml Web drag-and-drop design-time Chapter 16 - ASP.NET Server feature, Controls 485 and Data Binding Chapter 17 - Building Real-World driver manager, ODBC, 2-3 Web Applications Chapter 18 - Object-Relational Mapping in .NET

DROP TABLE statements, 803-804


DropDownList Control Data Binding (code listing), 559-560 Chapter 21 - Messaging using,558-560

Chapter 20 - COM Interoperability and ADO.NET Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Duwamish7 demo application, 639 Appendix A - Relational Databases: Some Basic Concepts Appendix dynamicBcursors, - Commonly 786-787 Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Index E


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and editing interfaces, and takes a comprehensive look at XML Editable DataGrid (code listing), 601-604 namespaces and classes, and how to integrate both with Editable DataList Control (code listing), 578-581 ADO.NET.

EditCommand event handler, 576 EditCommandColumn class, 599 TableEditing of Contents Rows Using BeginEdit, CancelEdit, and EndEdit methods (code listing), 119 Applied ADO.NET—Building Data-Driven EditItemTemplate code, 575-576 Solutions Introduction updating, and deleting through DataList control, 573-581 Chapter 1

- ADO.NET Basics

Chapter 2


editors, ASP.NET, 466-467

Employees.xls, Accessing Using ODBC Data Provider (code listing), 390 - ADO.NET in Disconnected Environments

Chapter 3

encapsulation (OR mapping), 637Environments Chapter 4 - ADO.NET in Connected Chapter 5 -Messages, Handling ADO.NET Encrypted SendingEvents (code listing), 751 Chapter 6 - Integrating XML with ADO.NET

encrypting messages, 750-751

Chapter 7


EnforceConstraints property, 123

Chapter 8

- Constraints and Data Relations Enterprise Planning (ERP) systems, 438 Chapter 9 -Resource ADO.NET Exception Handling Chapter 10 - Working with the ODBC Data Provider Enumerator, Implementation for an.NET (code listing), 442 Chapter 11 - Stored Procedures and Views environments Chapter 12 - Oracle, SQLXML, See and ADO.NET Other .NETin Data Providers ADO.NET in connected. connected environments Chapter 13 - Developing a Custom Data Provider in disconnected environments ADO.NET in disconnected. See ADO.NET Chapter 14 - Developing Database Web Applications using ASP.NET

error logs, SQL Server, 370


error messages and custom filters, 364-365


error severity levels,Real-World 368-369 Web Applications Chapter 17 - Building Chapter 18 - Object-Relational Mapping in .NET event handlers, defined, 209-210 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

events

Chapter 20 - COM Interoperability ColumnChanged, 222-223 and ADO.NET Chapter 21 - Messaging Connection, 211-215 Chapter 22 - SQL Server and ADO.NET: Notes on Performance DataAdapter, 215-220 Appendix A - Relational DataSet, 220-221 Databases: Some Basic Concepts Appendix B - Commonly DataTable, 221-226Used SQL Statements Appendix DataView C - ADO.NET and DataViewManager, Frequently Asked 229-231 Questions IndexFillError, 215, 217

handling List of Figures ADO.NET. SeeADO.NET events, handling InfoMessage, 211-212 List of Tables ListChanged, 229-230 List of Listings MergeFailed, 220-221 List of Sidebars

RowChanged, 222,224 RowDeleted, 222,225-226 RowUpdating and RowUpdated, 216,218-219 StateChange,211-212 XmlDataDocument,226-229

Excel databases, accessing, 389-390 exception handling in ADO.NET, 359-374 advantages of using, 360-365 custom filters and error messages, 364-365 nesting Try...Catch statements, 363 Try...Catch statements, 361-362

Try...Catch with multiple Catch statements, 363-364 Applied ADO.NET: Building Data-Driven Solutions Try...Catch...Finally statements, 362 ISBN:1590590732 code listings by Mahesh Chand and David Talbot Apress © 2003 (928 pages) Custom Filter and Error Message, Defining, 364-365 This text provides extensive of ADO.NET technology Nested Try...Catch and Multiple Catchcoverage Blocks, 363-364 including ADO.NET internals, namespaces, classes, and Opening a File, 360 interfaces, and takes a comprehensive look at XML Reading Data from SQL Server, 371-373 namespaces and classes, and how to integrate both with Simple Exception Handling Block, 361 ADO.NET. Simple Try...Catch Block, 362 SqlError and SqlErrorCollection objects, 373-374 Table of Try...Catch...Finally Contents Statement, 362 Applied ADO.NET—Building Data-Driven Solutions Exception classes, 365-366 Introduction fundamentals,359-360 Chapter - ADO.NET SQL1 Server 2000 Basics Chapter 2 368-369 - Data Components in Visual Studio .NET errors, Chapter SQL3 Server - ADO.NET error logs, in Disconnected 370 Environments SqlError and SqlErrorCollection classes, 373-374 Chapter 4 - ADO.NET in Connected Environments SqlException class, 371-373 Chapter 5 - Handling ADO.NET Events System.Data Exception 366-368 Chapter 6 - Integrating XML classes, with ADO.NET Chapter 7 - Data BindingClick and Windows Forms listing), Data-Bound Exchanging the Button Handler (code 329 Controls Chapter 8 - Constraints and Data Relations ExecuteNonQuery method, 158-159 Chapter 9


ExecuteQuery Method (code listing), 534


ExecuteReader method, 165 and Views Chapter 11 - Stored Procedures Chapter ExecuteScalar 12 - Oracle, method, SQLXML, 158-160 and Other .NET Data Providers Chapter 13 - Developing Data Provider ExecuteScalar Method atoCustom Retrieve Single Value (code listing), 160 Chapter 14 - Developing Database Web Applications using ASP.NET

ExecuteSQL Method (code listing), 504


ExecuteSqlQuery Method listing), 420 Binding Chapter 16 - ASP.NET Server(code Controls and Data ExecuteXmlReader method, 158 Chapter 17 - Building Real-World Web Applications Chapter 18 -Multiple Object-Relational Mapping .NET Executing SQL Queries UsinginSqlTransaction (code listing), 207-208 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Executing mySP Stored Procedure Using SQL Data Provider (code listing), 400-401


Export Text Wizard, 383-385


ExtendedProperties property, 93,123 Notes on Performance Chapter 22 - SQL Server and ADO.NET: Appendix - Relational (message Databases:queuing), Some Basic Concepts external Atransactions 747 Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Index F


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and fields, defined, 779 interfaces, and takes a comprehensive look at XML namespaces and classes, Fifth Normal Form (5NF or PJ/NF), 786 and how to integrate both with ADO.NET.

Fill methods defined, 170,188 of a DataAdapter, Calling (code listing), 177 TableFill of method Contents FillDataGrid and Form_Load Methods (code listing), 328 Applied ADO.NET—Building Data-Driven Solutions FillDataGrid and Page_Load Methods (code listing), 627,629 Introduction FillDataGrid Method (code listings), 305,323–324,341,419–420,503 Chapter 1 - ADO.NET Basics FillDataSet Method Generated by Data Form Chapter 2 - Data Components in Visual Studio .NETWizard (code listing), 69 FillPartialData Method (code listing), 628 Chapter 3 - ADO.NET in Disconnected Environments FillSchema method of SqlDataAdapter, Using (code listing), 172 Chapter 4


FillError5 event, 215,217 Chapter - Handling ADO.NET Events Chapter - Integrating XML with ADO.NET Filling a6 DataSet, 498–499 Chapter - Data Binding andTables Windows Forms Data-Bound Filling a7 DataSet from Two (code listing), 354 Controls Chapter 8


Chapter 9


Filling Data From Database to Data-Bound Controls (code listing), 478–480

Filling Data From Multiple Tables listing), 188–189 Chapter 10 - Working with the ODBC(code .NET Data Provider Chapter Filling data 11 - to Stored DataSet Procedures or DataReader and Views object, 25 Chapter 12 - Oracle, SQLXML, and Other411 .NET Data Providers Filling DataSets from multiple views, Chapter 13 - Developing a Custom Data Provider

Filling DatSet From DataAdapter (code listing), 498–499


filtering15 - Using ADO.NET in Xml Web Services Chapter

custom filters, 364–365 filter statements, defined, 112 Chapter 17 - Building Real-World Web Applications Filtering Queues Based on Category, Machine Name, and Label (code listing), 733–734 Chapter 18 - Object-Relational Mapping in .NET queues,734–735 Chapter 16 - ASP.NET Server Controls and Data Binding


Finding20 Rows in DataView Usingand Find Method (code listing), 131 Chapter - COM Interoperability ADO.NET FindRow (DataView), 131 Chapter 21 method - Messaging Chapter - SQL 161 Server and ADO.NET: Notes on Performance firehose22cursor, Appendix A - Relational Databases: Some Basic Concepts

First ASP.NET Application (code listing), 486–487


First Normal Form (1NF), 780–782


Font and Color Properties, Using DataGrid's (code listing), 320 Index List of Figures FoodMart 2000 database, 718 List of Tables

FOR XML keyword, 427–428

List of Listings

FOREIGN KEY Constraint, Creating (code listing), 347–348 constraints, defined, 346 ForeignKeyConstraint class, 346–348

List of Sidebars

foreign keys (relational databases), 779 form designer, creating templates with, 551 Form Load Event Handler (code listing), 304 Format and Parse Event Handlers, Adding (code listing), 292 Format event, 291–292 Format property page, 496–497 Formatting BoundColumn's Header and Footers (code listing), 588–589

Form_Load and FillDataGrid Methods (code listing), 328


Form's Constructor Calling CreateCustomersTable, and BindData (code listing), 101 ISBN:1590590732 by Mahesh Chand and David Talbot CreateOrdersTable, Apress © 2003 (928 pages) Form's Load Event Handler (code listing), 50–51 This (code text provides coverage of ADO.NET technology Form's Load Method listing),extensive 321 including ADO.NET internals, namespaces, classes, and

forward-only cursors, interfaces, 161,786–787 and takes a comprehensive look at XML namespaces and classes, and how to integrate both with

Fourth Normal Form (4NF), 785 ADO.NET. FoxPro,4

Frequently Asked Questions, ADO.NET, 811–845 Table of Contents Applied ADO.NET—Building Data-Driven Solutions Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Index G


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology ADO.NET internals, namespaces, classes, and Generate Datasetincluding property, 46-47 interfaces, and takes a comprehensive look at XML namespaces and classes, how to integrate both with Generic Data Access Class (code listing),and 771-773 ADO.NET.

Generic Data Access Class, Using (code listing), 774-775 generic data access components, writing, 770-775 Table of Contents

GetAttributes of a node (XML), 243-244


GetBlockedCategory Stored Procedure (code listing), 692-693 Introduction Chapter GetChanges 1 - ADO.NET methodBasics

defined, Chapter 2 - 125, Data192 Components in Visual Studio .NET saving and, 777 Chapter 3 -data ADO.NET in Disconnected Environments using, Chapter 4 842 - ADO.NET in Connected Environments Chapter 5 - Handling ADO.NET Events GetOrdersFromDatabase Method (code listing), 521 Chapter 6 Integrating XML with ADO.NET GetPageData Method (code listing), 816 Chapter 7


Chapter 8


grid lines, multiple columns, and alternating rows, 568-569

GridColumnStyles property, 314 Chapter 9 - ADO.NET Exception Handling Chapter GridTableStyleCollection 10 - Working with the members, ODBC .NET 314-315 Data Provider Chapter 11 - Stored Procedures and 507-515 Views guest book, creating (ASP.NET), Chapter 12 -507-508 Oracle, SQLXML, and Other .NET Data Providers basics, Chapter 13 - Developing a Custom Data Provider compiling and running, 514-515 Chapter 14 -Web Developing Database Web Applications using ASP.NET default Form: MyGuestBook.aspx, 508-511 Chapter Guest 15 Data, - Using Adding ADO.NET to Databases in Xml Web(code Services listing), 510

Web16Forms, adding, 511-514 Chapter - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Index H


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and HasChanges method, 126,192 interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with HasErrors property, 123 ADO.NET.

hash tables, 93

helper classes, DataGrid, 312-313 Table of Contents

Hitchhiker's Guide to Visual Basic and SQL Server,760


HitTest method, 324-334 Introduction DataGrid.HitTestInfo class, 324-326 Chapter 1 - ADO.NET Basics

getting -column header name, 332 Data Components in Visual Studio .NET hiding DataGrid columns, 332-334 Chapter 3 - ADO.NET in Disconnected Environments HitTest in Action (code listing), 325-326 Chapter 4 - ADO.NET in Connected Environments reshuffling DataGrid columns, 326-331 Chapter 2

Chapter 5


HTML 6 Chapter


of FancyBinding Page (code listing), 681-682 - Data Binding and Windows Forms Data-Bound Controls Page of Lazy Loading Page (code listing), 696-697 Chapter 8 - Constraints and Data Relations server controls, 481 Chapter 9 - ADO.NET Exception Handling Side of TestDataGrid Page (code listing), 677-678 Chapter 10 - Working with the ODBC .NET Data Provider of TestGridObjects Page (code listing), 679-680 Chapter 11 - Stored Procedures and Views View, creating templates with, 549-551 Chapter 12of- asp:DataGrid Oracle, SQLXML, andlisting), Other .NET View (code 501 Data Providers Chapter 7


HTTP (Hypertext Transfer Protocol), 517


HTTP-post HTTP-get, 518 Chapter 15 - and Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Index I


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology ADO.NET internals, namespaces, classes, and ID, Address, and including Name Columns of DataRow, Setting Values of (code listing), 95 interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate bothlisting), with ID and Name Data Columns of Customers Table, Creating (code 90 ADO.NET.

IDataReader interface properties and methods, 441-442 812-813 TableMeta-Data, of Contents

Applied ADO.NET—Building Data-Driven IDataRecord interface properties andSolutions methods, 442-443 Introduction

IDbCommand interface properties and methods, 440-441

Chapter 1

- ADO.NET Basics

IDbConnection interface properties and methods, 439-440 Chapter 2 - Data Components in Visual Studio .NET IDbDataAdapter interface/object properties and methods, 444-445 Chapter 3 - ADO.NET in Disconnected Environments Chapter 4 - ADO.NET in Connected Environments IDE (Integrated Development Environment), 33,39,466 Chapter 5

- Handling ADO.NET Events identity, mapped object, 637

Chapter 6


Chapter 7


IEnumerable, 675

Image,8Button, and TextBox Controls, Data Binding in (code listing), 561-562 Chapter - Constraints and Data Relations Chapter - ADO.NET Imports9directive, 137Exception Handling Chapter 10 - Working with the ODBCProcedure .NET Data Provider Incremental Lazy Loading Stored (code listing), 701 Chapter 11 - Stored Procedures and Views

indexing improving SQL Server performance using, 753-757 Chapter 13 - Developing a Custom Data Provider index strings, 694 Chapter 14 - Developing Database Web Applications using ASP.NET Index Tuning Wizard, 760 Chapter 15 - views, Using ADO.NET in Xml Web Services indexed 809 Chapter 16 ASP.NET Server Controls and Data Binding selecting columns for, 757-758 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers


InfiniteTimeout method, 745


InfoMessage and StateChange events, Writing Event Handlers for (code listing), 213 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding InfoMessage event, 211-212 Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging properties, 212 InfoMessageEventArgs Chapter 22 - SQL Server and ADO.NET: Notes on Performance

injection, SQL, 810


INSERT statements, 805


InsertAt C and RemoveAt Methods, Using (code listing), 116 Appendix - ADO.NET Frequently Asked Questions Index inserting, deleting, and updating through DataGrids, 342-344 List of Figures

Inserting XML Fragment into Document (code listing), 259

List of Tables

InsertOrder method, 530

List of Listings

interfaces, data provider, 438-445 List of Sidebars Command objects, 440-441 Connection objects, 439-440 grouped by function, 438 Reader objects, 441-443 internal transactions (message queuing), 747 Internet Explorer Web controls package, 693 interoperability COM.SeeCOM interoperability marshaling,710 isolation, component, 666-670

isolation levels ADO.NET: Building Data-Driven Solutions definition and Applied fundamentals, 788-789 ISBN:1590590732 by Mahesh for transactions, 200-201Chand and David Talbot Apress © 2003 (928 pages)

ItemTemplate code, 574



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Index J


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology joins and aliases,including 806-807ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces journal queues (system), 726and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Index K


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and keyset cursors, 786-787 interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.


- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Index L


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and language support, ASP.NET, 466 interfaces, and takes a comprehensive look at XML namespaces and199 classes, and how to integrate both with last in wins concurrency control, ADO.NET.

lazy loading, 695-705 leaf pages, 756 Table of Contents

ListBox Control binding methods and, 300 Introduction and ComboBox Controls, Binding (code listing), 305-306 Chapter 1 - ADO.NET Basics and ComboBox, data binding in, 304-306 Chapter - Data in Components in Visual Studio .NET Data2 Binding (code listing), 557-558 Chapter 3 -Control ADO.NET in Disconnected Environments ListBox Event Handler, Adding (code listing), 302-303 Chapter 4 556-558 - ADO.NET in Connected Environments using, Applied ADO.NET—Building Data-Driven Solutions

Chapter 5


Chapter 6


ListChanged event, 229-230

ListControl- class, 301-302 Data Binding and Windows Forms Data-Bound Controls ListControl (Web and Forms), Chapter 8 - class Constraints Data 555-556 Relations Chapter 7

Chapter 9 - DataBinding-related ADO.NET Exception Handling ListControl events, 302-303 Chapter 10 - Working with the ODBC .NET Data Provider

listings. Seecode listings


Load method (XmlDocument class), 252-253


LoadData GetDataSet Methods listing), 298-299 Chapter 13 -and Developing a Custom Data(code Provider Chapter 14 - Developing Database Web Applications using ASP.NET LoadDataSet Method Generated by Data Form Wizard (code listing), 68-69 Chapter 15 Using ADO.NET in Xml Web Services LoadXml method, 269 Chapter 16 - ASP.NET Server Controls and Data Binding

LOBs (Large Object Binary data types), 425


locking,18 788-791 Chapter - Object-Relational Mapping in .NET isolation levels, 788-789 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding locking modes, 790-791


locks, avoiding, 766 Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on listing), Performance Login Button Click Event Handler Code (code 613 Appendix A - Relational Databases: Some Basic Concepts

Login.aspx page (Online Job Board Application), 612-615



Index M


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and managed classes, 10 interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with managed code, 10,709 ADO.NET.

manual coding vs. IDE, 39

manual vs. designer development mode, 775 Table of Contents

mapped objects caching mechanism, near-zero- impact, 706–708 Introduction code listings Chapter 1 - ADO.NET Basics Adding Videos() Array to VideoCategory Object, 695–696 Chapter Code-Behind 2 - Data Components in Visual Studio .NET 676–677 File of TestDataGrid Program, Chapter Code-Behind 3 - ADO.NETObject in Disconnected Environments of FancyBinding Page, 682–684 Chapter Code-Behind 4 - ADO.NETObject in Connected Environments of LazyLoading Page, 697–700 Chapter GetBlockedCategory 5 - Handling ADO.NET Events Stored Procedure, 692–693 Chapter HTML 6 - Integrating XML with ADO.NET of FancyBinding Page, 681–682 Chapter HTML 7 - Data of TestGridObjects Binding and Windows Page,Forms 679–680 Data-Bound Controls HTML Page of Lazy Loading Page, 696–697 Chapter 8 - Constraints and Data Relations Side of TestDataGrid Page, 677–678 Chapter HTML 9 - ADO.NET Exception Handling Incremental Lazy Loading Stored Procedure, Chapter 10 - Working with the ODBC .NET Data Provider701 Theoretical Shopping Cart Example, 680–681 Chapter 11 - Stored Procedures and Views and Related Objects, 686–691 Chapter VideoCategory 12 - Oracle, SQLXML, and Other .NET Data Providers VideoCategoryIndexer, 701–703 Chapter 13 - Developing a Custom Data Provider VideoCategoryIndexer Test Case, 703–704 Chapter 14 - Developing Database Web Applications using ASP.NET WeakCache Object, 707–708 Chapter 15 - Using ADO.NET in Xml Web Services creating,644–648 Chapter 16 - ASP.NET Server Controls and Data Binding data binding and, 675–684 Chapter 17 - Building Real-World Web Applications bound objects, accessing properties of, 678–680 Chapter bound 18 - Object-Relational Mapping .NET objects, using logic with,in680–685 Chapter connection 19 - Mapped Objects: Performance Considerations and Data Binding strings, 676 Chapter 20 - COM definition and Interoperability fundamentals, and 641ADO.NET Chapter 21master-detail - Messaging relationships, 694–705 large Chapter incremental 22 - SQL Server ADO.NET: Notes700–705 on Performance lazyand loading schemes, Appendixlazy A - loading, Relational 695–700 Databases: Some Basic Concepts detail when is loaded, 705 Appendixloading B - Commonly Usedmaster SQL Statements master-detail relationships, problematic, 684–694 Appendix C - ADO.NET Frequently Asked Questions highly nested structures, 685–691 Index large tree structures, 691–693 List of Figures tree optimization, 693–694 List of Tables mappings List of Listings column,45 List of Sidebars object-relational in .NET. Seeobject- relational (OR) mapping in .NET table,45–46 Applied ADO.NET—Building Data-Driven Solutions

marshaling, interoperability, 710 master-detail relationships defined, 99 problematic,684–694 highly nested structures, 685–691 large tree structures, 691–693 tree optimization, 693–694 working with large, 694–705 incremental lazy loading schemes, 700–705

lazy loading, 695–700 Applied ADO.NET: Building Data-Driven Solutions loading detail when master is loaded, 705 by Mahesh Chand and David Talbot

materialized views, 809 Apress © 2003 (928 pages)

ISBN:1590590732

MaxLength property, This 93–94 text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Merging interfaces, and takes a comprehensive look at XML DataRow andnamespaces DataTable Objects (code listing), and classes, and how to127 integrate both with DataRow, DataTable or DataSet, 126–127 ADO.NET. Merge method, 126–127 MergeFailed event, 220–221 TableMergeFailed of ContentsEvent Handler, Calling (code listing), 220–221 Applied ADO.NET—Building Solutions Two DataSet Objects Data-Driven (code listing), 189 Introduction Two DataSets (code listing), 126–127 Chapter 1

- ADO.NET Basics MessagePriority Enumeration members, 746

Chapter 2


messaging,725–752 - ADO.NET in Disconnected Environments code listings Chapter 4 - ADO.NET in Connected Environments Creating a Queue, 737 Chapter 5 - Handling ADO.NET Events Deleting a Queue, 738 Chapter 6 - Integrating XML with ADO.NET Encrypted Messages, Sending, 751 Chapter Filtering 7 - Data BindingBased and Windows Forms Data-Bound Controls Queues on Category, Machine Name, and Label, 733–734 Chapter Getting 8 - Constraints and Data Relations a Queue's Properties, 738 Chapter Private 9 - ADO.NET Exception Handling and Public Queues, Retrieving, 732–733 Chapter Receiving 10 - Working with thefrom ODBC Data Provider Messages a .NET Queue, 743–744 Chapter Sending 11 - Stored Views andProcedures Receiving and Transactional Messages, 749–750 Chapter Sending 12 - Oracle, Messages SQLXML, toand a Queue, Other .NET 743 Data Providers encrypting messages, 750–751 Chapter 13 - Developing a Custom Data Provider message queuing Database Web Applications using ASP.NET Chapter 14 - Developing creating and deletinginmessage Chapter 15 - Using ADO.NET Xml Web queues Servicesprogrammatically, 735–736 fundamentals, 725 Chapter 16 - ASP.NET Server Controls and Data Binding 726–727 Chapter installing, 17 - Building Real-World Web Applications managing queues with VS .NET, 731–732 Chapter 18 - Object-Relational Mapping in .NET MessageQueue class properties, 729–730 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding MessageQueue instance, creating, 738–739 Chapter 20 - COM Interoperability and ADO.NET MessageQueueCriteria, filtering queues with, 734–735 Chapter 21 - Messaging MessageQueueTransaction class, 747 Chapter 22 - SQL Server and ADO.NET: Notes on Performance queue path, setting, 739–740 Appendixretrieving A - Relational Databases: Basic Concepts available queues,Some 732–734 Appendixsample B - Commonly Usedcreating, SQL Statements application, 736–738 Appendixsending C - ADO.NET Frequently Asked Questions and receiving messages, 740–741 Index simple messaging application, creating, 741–745 List of Figures System.Messaging namespace, 727–728 List of Tables types of message queues, 725–726 transactional messaging, 747–750 List of Listings working with messages, 745–750 List of Sidebars creating and removing, 745 setting queue and message priorities, 746 Chapter 3

meta-data, defined, 780 MFC (Microsoft Foundation Classes) overview, 5 Microsoft Access, 4,43 Microsoft Data Access Technologies, overview, 2–7 ADO,6 ADO.NET,6–7 DAO,4–5 MFC,5

ODBC,2–4 OLE DB, 5–6 Applied ADO.NET: Building Data-Driven Solutions ISBN:1590590732 by Mahesh Chand and David Talbot RDO, 5 Apress © 2003 (928 pages)

Microsoft Message Queuing (MSMQ), 725


Microsoft .NET Class including Library, ADO.NET 465 internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

Microsoft Transaction Server and (MTS), 7 and how to integrate both with namespaces classes, ADO.NET. Microsoft Universal Description, Discovery and Integration (UDDI) Business Registry, 526 Microsoft Visual Studio .NET (VS .NET). SeeVisual Studio .NET Table of Contents Microsoft.Data.Odbc namespace, 377, Applied ADO.NET—Building Data-Driven Solutions

Microsoft.Data.SqlXml namespace, 427

Introduction

Mobile Internet Toolkit, ASP.NET, 388 466–467 - ADO.NET Basics

Chapter 1

Move Next, MoveComponents Previous, Move First,Studio Move.NET Last Button Code (code listing), 299 Chapter 2 - Data in Visual Chapter 3 - ADO.NET in Disconnected MoveToContent method (nodes), 242Environments Chapter 4

- ADO.NET in Connected Environments MoveToContent Method, Using (code listing), 243

Chapter 5


Chapter 6


MoveToMethod (nodes), 242

Moving7Record Click Handlers (code listing), 337–338 Chapter - DataButton Binding and Event Windows Forms Data-Bound Controls Chapter Constraints and Data Relations Moving8to -Root and First Child Nodes Using XPathNavigator (code listing), 274–275 Chapter 9 ADO.NET Exception Handling msadomd.dll library, 718–719 Chapter 10 - Working with the ODBC .NET Data Provider

MSXML (Microsoft XML), 6


multi-item controls, Chapter 12 -data-bound Oracle, SQLXML, and 488 Other .NET Data Providers Chapter multiple13Catch - Developing statements, a Custom 363–364 Data Provider Chapter - Developing Database Applications ASP.NET multiple14columns, grid lines, andWeb alternating rows,using 568–569 Chapter 15 - Using ADO.NET in Xml Web Services

multiple tables, filling DataSet from, 188–189


multiple17views Chapter - Building Real-World Web Applications creating,195–197 filling DataSets from, 411

Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

My Home View Guestand Book Buttons (code listing), 514 Chapter 20 -Page COM and Interoperability ADO.NET Chapter 21 -67 Messaging MyDS.xsd, Chapter - SQL Server and ADO.NET: Notes on Performance MySQL22 Database Appendix A - Relational Databases: and .NET data provider, 435 Some Basic Concepts Appendix B - Commonly accessing, 380–382Used SQL Statements Appendix C - ADO.NET Frequently Accessing (code listing), 382Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Index N


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and namespaces interfaces, and takes a comprehensive look at XML and classes overview, 13-14 namespaces and classes, and how to integrate both with data provider,ADO.NET. 38

importing,137 references, adding, 23-24 TableSystem.SqlClient, of Contents 137-139 Applied ADO.NET—Building Data-Driven Solutions

Navigation and DataGrid sorting, setting, 318-319

Introduction

nested 1data relations,Basics 356 Chapter - ADO.NET Chapter nested 2structures, - Data Components 685-691 in Visual Studio .NET Chapter - ADO.NET 198 in Disconnected Environments nested 3transactions, Chapter 4


Chapter 5


Nested Try...Catch and Multiple Catch Blocks (code listing), 363-364

nesting6Try...Catch statements, Chapter - Integrating XML with 363 ADO.NET .NET 7 Chapter


1.1 8updates, implementing, Chapter - Constraints and Data391 Relations Base Class Library, 14 Chapter 9 - ADO.NET Exception Handling Common Language (CLR) services, 1 Chapter 10 - Working withRuntime the ODBC .NET Data Provider data provider, MySQL and, 435 Chapter 11 - Stored Procedures and Views data providers, choosing, 22-23 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Framework and XML, 233-238 Chapter 13 - Developing a Custom Data Provider Document Object Model (DOM) interfaces, 237 Chapter 14 - Developing Database Web Applications using ASP.NET System.Xml namespace, 234-235 Chapter 15 - Using ADO.NET in Xml Web Services System.Xml namespace reference, adding, 238 Chapter 16 - ASP.NET Server Controls and Data Binding System.Xml.Schema namespace, 235 Chapter System.Xml.Serialization 17 - Building Real-World Web Applications namespace, 236 Chapter System.Xml.XPath 18 - Object-Relational Mapping in 236 .NET namespace, Chapter System.Xml.Xsl 19 - Mapped Objects: Performance namespace, 236 Considerations and Data Binding Chapter XML 20 - COM and ADO.NET .NETInteroperability architecture, 237-238 Chapter 21 - Messaging Framework Class Library, 366 Chapter Framework 22 - SQLinterop Server tools, and ADO.NET: 710-712 Notes on Performance Library Exporter (Tlbexp.exe), 712 AppendixType A - Relational Databases: Some Basic Concepts Type Library Importer (Tlbimp.exe), 711 Appendix B - Commonly Used SQL Statements Studio .NET, 710 Asked Questions AppendixVisual C - ADO.NET Frequently Framework Library Index data providers in, 38 List of Figures server-side controls and, 483-485 List of Tables XML Web services and, 518 List of Listings Runtime Class Library, 76 List of Sidebars Software Development Kit (SDK), 376,710 XML API, 237 New Query Wizard (Access), 43 nodes Adding a Node With Attributes (code listing), 260 adding attributes to, 259-260 adding to documents, 256 GetAttributes of (XML), 243-244 getting root, 256 node information, getting (XML), 239-242 NodeChanged Event Handler (code listing), 228

NodeInserted Event Handler (code listing), 229 Applied ADO.NET: Building Data-Driven Solutions NodeRemoved Event Handler (code listing), 229 ISBN:1590590732 Chand (code and David Talbot Nodes, AddingbytoMahesh a Document listing), 256 Apress © 2003 (928 pages) removing and replacing, 257 text244 provides extensive coverage of ADO.NET technology searching for This (XML), including ADO.NET internals, namespaces, classes, and

nonrepeatable reads, 788 and takes a comprehensive look at XML interfaces, namespaces and classes, and how to integrate both with normalization,780-786 ADO.NET. Boyce-Codd Normal Form (BCNF), 780,785 Fifth Normal Form (5NF or PJ/NF), 786 Normal Form (1NF), 780-782 TableFirst of Contents Fourth Normal Form (4NF), 785 Solutions Applied ADO.NET—Building Data-Driven Second Normal Form (2NF), 782-784 Introduction Third Form (3NF), 784-785 Chapter 1 Normal - ADO.NET Basics Chapter NOT NULL 2 - Data constraints, Components defined, in Visual 345 Studio .NET Chapter 3 - ADO.NET in Disconnected Environments NotSupportedException, 445-447 Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9


null values, 647


Index O


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology ADO.NET internals, namespaces, classes, and object databases,including 639–640 interfaces, and takes a comprehensive look at XML namespaces andinclasses, and how to integrate both with object-relational (OR) mapping .NET, 637–673 ADO.NET. advantages of, 640

code listings SelectVideosCheckedOutToUser,665 Table of Contents User Object in the User Component, 655–656 Applied ADO.NET—Building Data-Driven Solutions UserData Object in the User Component, 656–657 Introduction UserDataAccess Object in the User Component, 657–659 Chapter 1 - ADO.NET Basics UserTestCase Object, 660–661 Chapter 2 - Data Components in Visual Studio .NET VideoCheckInCheckOut Component, Test Case for, 671–673 Chapter VideoCheckInCheckOut 3 - ADO.NET in Disconnected Environments Object, 667–670 Chapter VideoTape 4 - ADO.NET in Connected Environments Component, Test Case for, 653–654 Chapter VideoTape 5 - Handling ADO.NET Events Object, 645–648 Chapter VideoTapeData 6 - Integrating XML with ADO.NET Object, 643–644 Chapter VideoTapeDataAccess 7 - Data Binding and Windows Data-Bound Controls Object, Forms 648–652 Chapter DataSet 8 - Constraints inadequacy, and 638 Data Relations design Chapter 9 -tradeoffs, ADO.NET 665–673 Exception Handling isolation, Chapter component 10 - Working with the 666–667 ODBC .NET Data Provider workaround, Chapter component 11 - Stored isolation Procedures and Views 667–670 procedures, logic 665–666 Chapter stored 12 - Oracle, SQLXML, andin, Other .NET Data Providers VideoCheckInCheckOut test case, creating, 670–673 Chapter 13 - Developing a Custom Data Provider fundamentals, 637 Chapter 14 - Developing Database Web Applications using ASP.NET object databases, 639–640 Chapter 15 - Using ADO.NET in Xml Web Services Video Store Application, basic design, 640–665 Chapter 16 - ASP.NET Server Controls and Data Binding Check In/Check Out component, 663–665 Chapter 17 - Building Real-World Web Applications data access component, 648–652 Chapter 18 - Object-Relational Mapping in .NET data object, 643–644 Chapter database 19 - Mapped Objects: Performance Considerations and Data Binding design, 641–643 Chapter dependencies, 20 - COM Interoperability ADO.NET managing,and 661–662 Chapter mapped 21 - Messaging object, 644–648 Chapter User 22 - SQL Server and ADO.NET: Notes on Performance component, 654–659 AppendixUser A - Relational Databases: test case, 659–661 Some Basic Concepts Appendixvideo B - Commonly tape test case, Used SQL building, Statements 652–654 Appendix C - ADO.NET Frequently Asked Questions ODBC .NET data provider, 375–391 IndexAccess databases, accessing, 378–380 List of Figures basics, 375 List of Tables code listings List of Listings Employees.xls, Accessing Using ODBC Data Provider, 390

MySQL Database, Accessing, 382 List of Sidebars Reading Data from Northwind Using ODBC Data Provider, 379–380 TextDB.txt file, Accessing, 388 Excel databases, accessing, 389–390 installing,376–377 MySQL databases, accessing, 380–382 .NET 1.1 updates, implementing, 391 ODBC .NET data provider classes, 377–378 text file databases, accessing, 382–388 accessing text files, 385–388 exporting Access table to text file, 383–385 ODBC (Open Database Connectivity)

basics,2–4 Applied ADO.NET: Building Data-Driven Solutions data source names (DSNs), 34,80,832–833 ISBN:1590590732 by Mahesh Chand and David Talbot drivers,80 Apress © 2003 (928 pages) ODBC DSNs, Reading (code listing), 832–833 This 38 text provides extensive coverage of ADO.NET technology OdbcConnection, including ADO.NET internals, namespaces, classes, and

ODP.NET data provider, 414 interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with OLAP (On-Line Analytical Processing) ADO.NET. server cubes, 718 server data, accessing, 718–724 Table Contents OLEof DB (Object Linking and Embedding Database) Applied ADO.NET—Building OleDb data provider Data-Driven Solutions Introduction compared to others, 80 Chapter implementing 1 - ADO.NET transactions Basics in, 820–821 Chapter Oracle 2 - Data databases Components and,in414 Visual Studio .NET

OleDb Connecting to (code listing), 143 Chapter 3 -Database, ADO.NET in Disconnected Environments OleDbCommand, creating andEnvironments using, 153–154 Chapter 4 - ADO.NET in Connected OleDbCommand, Using to Events Access an Access Database (code listing), 154 Chapter 5 - Handling ADO.NET OleDbConnection, Chapter 6 - Integrating38 XML with ADO.NET OleDbConnection class, Chapter 7 - Data Binding and 140 Windows Forms Data-Bound Controls OleDbDataAdapter command properties, 169 - Constraints and Data Relations overview of, 5–6 Chapter 9 - ADO.NET Exception Handling services settings, 146–147 Chapter 8


On Error (VB), 359and Views Chapter 11statements - Stored Procedures Chapter OnDataBinding 12 - Oracle, method, SQLXML, 539and Other .NET Data Providers Chapter Developing a Custom Data Provider Online 13 Job- Board Application Chapter 14 - Developing Database Web Applications using ASP.NET database schema, 610–611 Chapter 15 - Using ADO.NET in Xml Web Services developing, 611–635 Chapter Contact.aspx 16 - ASP.NET page, Server617–618 Controls and Data Binding Chapter DisplayData.aspx 17 - Building Real-World and Resumes.aspx Web Applications pages, 623–632

page,Mapping 632–633in .NET Chapter dnjHeader.aspx 18 - Object-Relational 635–636 Chapter improving/modifying 19 - Mapped Objects:application, Performance Considerations and Data Binding page, 612–615and ADO.NET Chapter Login.aspx 20 - COM Interoperability page, 618–620 Chapter PostJob.aspx 21 - Messaging page, 620–623 Chapter PostResume.aspx 22 - SQL Server and ADO.NET: Notes on Performance Register.aspx page, 615–616 running the application, 633–635 Appendix B - Commonly Used SQL Statements specifications, 609–610

Appendix A - Relational Databases: Some Basic Concepts Appendix C - ADO.NET Frequently Asked Questions

Opening a File (code listing), 360 Index List optimistic of Figures concurrency

ADO.NET List of Tables default, 44 control, 199 List of Listings Optimistic List of Sidebars Concurrency (code listing), 202–203 optimistic locking, 790–791 Oracle Database, Connecting to (code listing), 417–418 Enterprise Manager, 393 managed provider, 413 Oracle .NET data provider, 413–426 adding reference to, 415 basics,413–414 classes,416–425 BFILEs and LOBs, reading, 425 connections, creating, 416–418

OracleConnection class, 416–417 Applied ADO.NET: Building Data-Driven Solutions OracleDataReader class, 421–423 ISBN:1590590732 bydata Mahesh Chand and David421–423 Talbot reading fast using DataReader, Apress © 2003 (928 pages) reading/writing data using DataAdapter, 423–424 This textexecuting, provides extensive SQL commands, 418–421 coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and code listings interfaces, and takes a comprehensive look at XML Connectingnamespaces to an Oracle 417–418 andDatabase, classes, and how to integrate both with Constructing SQL INSERT, UPDATE, DELETE Queries, 421 ADO.NET. ExecuteSqlQuery Method, 420 FillDataGrid Method, 419–420 Table of Oracle-Specific Contents DataReader Methods, 423 Applied ADO.NET—Building Data-Driven Solutions OracleDataAdapter, Reading/Writing Data Using, 423–424 Introduction OracleDataReader, Reading Data Using, 422–423 Chapter 1

- ADO.NET Basics

Chapter 2


OracleClient data provider, 770

Ordinal and MaxLength properties, Using (code listing), 94 - ADO.NET in Disconnected Environments

Chapter 3

Ordinal4property, 93–94 Chapter - ADO.NET in Connected Environments Chapter - HandlingExecuting ADO.NET Stored Events Procedures with (code listing), 404–405 Output 5Parameter, Chapter 6 - Integrating XML with ADO.NET Chapter 7


Chapter 8


Chapter 9



Index P


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology internals, namespaces, classes, and Page and Controlincluding classes ADO.NET in data binding, 539 interfaces, and takes a comprehensive look at XML namespaces and classes, and how(code to integrate both PageIndexChanged Handler of DataGrid Control listing), 500with ADO.NET.

Page_Load and FillDataGrid Methods (code listing), 627,629

Page_Load Event Handler Code of ViewGuestBook.aspx (code listing), 512-513 Table of Contents

paging in DataGrid control, 499-500 Introduction defined, 708 Chapter 1 - ADO.NET Basics enabling programmatically, 500-502 Chapter 2 - Data Components in 815-820 Visual Studio .NET implementing in ADO.NET, Chapter 3 - ADO.NET in Disconnected Implementing in ADO.NET (code Environments listing), 817-820 Chapter 4 -property ADO.NETpage, in Connected Environments Paging 496 Applied ADO.NET—Building Data-Driven Solutions

Chapter 5


Chapter 6


ParameterDirection members (stored procedures), 402

parameters - Data Binding and Windows Forms Data-Bound Controls construction of, 184-187 Chapter 8 - Constraints and Data Relations Creating (code listing), 185-186 Chapter 9 - ADO.NET Exception Handling Using in Stored Procedures (code listing), 402-404 Chapter 7


paranoid 662 and Views Chapter 11 programming, - Stored Procedures parent/child relationship, 99 and Other .NET Data Providers Chapter 12 - Oracle, SQLXML, Chapter - Developing a Custom Data Provider parent 13 table, 99 Chapter 14 - Developing Database Web Applications using ASP.NET

ParentRelations property (DataTable), 99-101


Parse and Format Event Handlers, Adding (code listing), 292


Parse event, 291-292 Chapter 17 - Building Real-World Web Applications Chapter 18 different - Object-Relational Mapping in .NET paths for queues, 739-740 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Pessimistic Concurrency (code listing), 204


pessimistic concurrency control, 199


pessimistic 790-791 Chapter 22 - locking, SQL Server and ADO.NET: Notes on Performance Appendix - Relational phantomA records, 788Databases: Some Basic Concepts Appendix B - Commonly pipe-delimited format, Used 438 SQL Statements Appendix C - ADO.NET Frequently Asked Questions

piped format file, 446

Index

PipedDataAdapter object, 460-462 List of Figures List PipedDataCommand of Tables object, 449-453 List of Listings PipedDataConnection object, 446-449 List of Sidebars

PipedDataProvider application, testing, 462-463 PipedDataProvider Test Case (code listing), 463 PipedDataReader object, 453-459 PJ/NF (Fifth Normal Form), 786 platform requirements, ASP.NET, 466 pooling connection,145-149 Connection strings and, 777 session,146 Populating an Order in Database, Web Service Method for (code listing), 530-531

Post Job Button Click Event Handler (code listing), 619


Post Resume Button Click Event Handler (code listing), 622-623 ISBN:1590590732 by Mahesh Chand and David Talbot Post Resume Page, Adding Options to (code listing), 621-622 Apress © 2003 (928 pages) This618-620 text provides extensive coverage of ADO.NET technology PostJob.aspx page, including ADO.NET internals, namespaces, classes, and

PostResume.aspx page, 620-623 interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Prepare method (SqlCommand), 160 ADO.NET.

Preview Data property, 46-47 primary keys defined, 779 Applied ADO.NET—Building Data-Driven Solutions PRIMARY KEY constraints Introduction adding,352 Chapter defined, 1 - ADO.NET 345 Basics

Table of Contents

Chapter 2


Chapter 3


Private Members (code listing), 196-197

Private4Queues, Retrieving (code listing), 732 Chapter - ADO.NET in Connected Environments Chapter private 5queues - Handling (user), ADO.NET 726 Events Chapter - Integrating private 6system queues,XML 726 with ADO.NET Chapter 7


Profiler, SQL Server, 758-762

Chapter 8

- Constraints and Data Relations Property 493-494, 581-582 Chapter 9 Builder, - ADO.NET Exception Handling

PropertyCollection 93 ODBC .NET Data Provider Chapter 10 - Workingclass, with the Chapter 11 - Stored and Procedures and Views 295-296 PropertyManager CurrencyManager, Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

proxy files (Service1 .vb), 527


Public Queues, Retrieving (code listing), 732-733


public queues (user), 726 in Xml Web Services Chapter 15 - Using ADO.NET Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Index Q


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Query Analyzer, 760–761 interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Query Builder, 43–44, 45 ADO.NET.

Query from SelectVideosCheckedIn, Not Optimized (code listing), 762–763 Queue's Properties, Getting a (code listing), 738 Table of Contents

queues, transactional, 748


queuing, message Introduction creating/deleting queues programmatically, 735–736 Chapter 1 - ADO.NET message Basics fundamentals, 725 - Data Components in Visual Studio .NET installing,726–727 Chapter 3 - ADO.NET in Disconnected Environments managing queues with VS .NET, 731–732 Chapter 4 - ADO.NET in Connected Environments MessageQueue class properties, 729–730 Chapter 5 - Handling ADO.NET Events MessageQueue instance, creating, 738–739 Chapter 6 - Integrating XML with ADO.NET MessageQueueCriteria, filtering queues with, 734–735 Chapter 7 path, - Datasetting, Binding739–740 and Windows Forms Data-Bound Controls queue Chapter 8 - Constraints and Data732–734 Relations retrieving available queues, Chapter 9 - application, ADO.NET Exception Handling sample 736–738 Chapter 10 - Working with the ODBC .NET Data Provider sending/receiving messages, 740–741 Chapter 11 -queue Storedand Procedures and Views 746 setting message priorities, Chapter simple 12 -messaging Oracle, SQLXML, application, and Other 741–745 .NET Data Providers System.Messaging namespace, 727–728 Chapter 13 - Developing a Custom Data Provider types message queues, 725–726 Chapter 14of - Developing Database Web Applications using ASP.NET Chapter 2

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Index R


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Raising ListBox Events (code listing), 303 interfaces, and takes a comprehensive look at XML namespaces and(RAD) classes, anddevelopment, how to integrate Rapid Application Development Web 488both with ADO.NET.

RDO (Remote Data Objects), overview of, 5 Read method (DataReader), 162 Table of Contents

read-only data binding, 537


Reader objects. See alsoDataReader;PipedDataReader object,441-443 Introduction Chapter Reading 1 - ADO.NET Basics

All Bindings a Form (code listing), 290-291 Chapter 2 - DataofComponents in Visual Studio .NET All Constraints of a (code listing), 352 Chapter 3 - ADO.NET in Collection Disconnected Environments All Controls Participating in Data Binding (code listing), 294 Chapter 4 - ADO.NET in Connected Environments Data5 from Northwind UsingEvents ODBC Data Provider (code listing), 379-380 Chapter - Handling ADO.NET Data6 from SQL Server listing), 371-373 Chapter - Integrating XML(code with ADO.NET

Database Schema Programmatically (code listing), 825 - Data Binding and Windows Forms Data-Bound Controls DataSet Columns and Their Data Types (code listing), 814-815 Chapter 8 - Constraints and Data Relations Only Modified Rows of DataSet (code listing), 843 Chapter 9 - ADO.NET Exception Handling TextBox Control's Binding Properties (code listing), 291-292 Chapter 10 - Working with the ODBC .NET Data Provider and Writing to and from Windows Registry (code listing), 831 Chapter 11 - Stored Procedures and Views an XML File (code listing), 239 Chapter 7


reading XML, 238-246 closing document, 245-246 Chapter 14 - Developing Database Web Applications using ASP.NET fundamentals,238-239 Chapter 15 - Using ADO.NET in Xml Web Services GetAttributes of a node, 243-244 Chapter 16 - ASP.NET Server Controls and Data Binding getting node information, 239-242 Chapter 17 - to Building Real-World Web Applications moving content node, 242-243 Chapter 18 - Object-Relational searching for a node, 244Mapping in .NET Chapter 13 - Developing a Custom Data Provider


ReadXml method, 122,127,262-263


ReadXmlSchema method, 127,264 Chapter 21 - Messaging Rearranging a DataGrid Column's Sequence listing), 588 Chapter 22 - SQL Server and ADO.NET: Notes on(code Performance Appendix - Relational Databases: Some ReceiveAmethod (MessageQueue), 741Basic Concepts Appendix B - Commonly Used SQL Statements

Receiving and Sending Transactional Messages (code listing), 749-750


Receiving Messages from a Queue (code listing), 743-744

Index

Record Button Click Event Handlers, Moving (code listing), 337-338 List of Figures List of Tables record navigation system List of Listings296-300 building, List of building Sidebars DataGrid, 335-338

Record Navigation System Variables (code listing), 298 RecordSets Creating Custom (code listing), 337 and cursors, 786-787 vs. DataSets, 12 defined, 121 Filling DataAdapter from, 175-176 reference materials ADO Examples and Best Practices for Programmers ,760 ADO.NET,760 Building Distributed Applications with Microsoft .NET ,776

Concurrency Control and Recovery in Database Systems ,789 Applied ADO.NET: Building Data-Driven Solutions Hitchhiker's Guide to Visual Basic and SQL Server,760 ISBN:1590590732 by Mahesh relational databases info,Chand 792 and David Talbot Apress © 2003 (928 pages) SQL online references, 810 This text provides extensive coverage of, 791 ADO.NET technology Transaction Processing: Concepts and Techniques including ADO.NET internals, namespaces, classes, and

references, adding to Oracle .NET data provider, 415 look at XML interfaces, and takes a comprehensive namespaces and classes, and how to integrate both with RefreshSchema method, 184 ADO.NET.

Register.aspx Code (code listing), 616 Register.aspx page (Online Job Board application), 615-616

Table of Contents

Registry, Windows, 828-831 Applied ADO.NET—Building Data-Driven Solutions Introduction RejectChanges method (DataRow), 95-96,127,191-192,231 Chapter 1 databases, - ADO.NET Basics relational 779-792 Chapter 2 - Data Components fundamentals, 779-780 in Visual Studio .NET Chapter 3 -788-791 ADO.NET in Disconnected Environments locking, Chapter isolation 4 - ADO.NET Connected Environments levels,in788-789 Chapter locking 5 - Handling ADO.NET modes, 790-791Events Chapter normalization, 6 - Integrating 780-786 XML with ADO.NET

Normal (BCNF), Chapter Boyce-Codd 7 - Data Binding andForm Windows Forms785 Data-Bound Controls Form (5Data NF or PJ/NF), 786 Chapter Fifth 8 - Normal Constraints and Relations (1 NF), 780-782 Chapter First 9 - Normal ADO.NETForm Exception Handling Normalwith Form NF),.NET 785 Data Provider Chapter Fourth 10 - Working the (4 ODBC Normal Form (2 NF), 782-784 Chapter Second 11 - Stored Procedures and Views

Third Normal Form (3 NF), 784-785 online resources, 792 Chapter 13 - Developing a Custom Data Provider recordsets and cursors, 786-787

Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 14 - Developing Database Web Applications using ASP.NET

Relations 124 Chapter 15 property, - Using ADO.NET in Xml Web Services Chapter ReleaseObjectPool, 16 - ASP.NET Server CallingControls (code listing), and Data 149Binding Chapter 17 - Building Real-World Web Applications Removing Chapter 18 - Object-Relational in .NET All Items of a Node (codeMapping listing), 257 Chapter 19 - Mapped Performance Considerations and Data Binding Column From a Objects: Collection (code listing), 117 Chapter 20 - COM and ADO.NET RemoveAll forInteroperability books.xml, Calling (code listing), 258 Chapter RemoveHandler 21 - Messaging statement, 209

a Row Method a Performance DataAdapter (code listing), 177 Chapter 22 -and SQLCalling Serverthe andUpdate ADO.NET: Notesofon Appendix A control - Relational Databases: Repeater (Web Forms) Some Basic Concepts Appendix B - Commonly Used SQL Statements supporting templates, 548 Appendix C552-555 - ADO.NET Frequently Asked Questions using, Index ReplaceChild, Calling (code listing), 258 List of Figures

report queues (system), 726

List of Tables

ResetCommandTimeout method (SqlCommand), 160 List of Listings List ReshuffleColumns of Sidebars Method (code listing), 329-330

reshuffling DataGrid columns, 326-331 response queues (user), 726 Resumes.aspx HTML View (code listing), 630-632 Resumes.aspx pages (Online Job Board Application), 623-632 retrieving data, 775-777 Rollback, Commit, and Savepoints, 204-206 root nodes, getting, 256 rows Adding to DataTable Using DataRow (code listing), 96-98

and DataTable operations Applied ADO.NET: Building Data-Driven Solutions adding,106, 109-110 ISBN:1590590732 by 110-111 Mahesh Chand and David Talbot deleting, 106, Apress © 2003 (928 pages) editing,119 text provides extensive coverage of ADO.NET technology searching,This 106,112-113 including ADO.NET internals, namespaces, classes, and sorting, 106,113-114 interfaces, and takes a comprehensive look at XML of DataView, Adding, Updating, and Deleting listing),both 130 with namespaces and classes, and how(code to integrate deleting, 176 ADO.NET. RowChanged event, 222,224 RowChanging and RowChanged Event Handlers, Writing (code listing), 224 TableRowDeleted of Contentsevent, 222, 225-226 Applied ADO.NET—Building Data-Driven Solutions RowDeleting and RowDeleted Event Handlers, Writing (code listing), 225-226 Introduction RowFilter property (DataView), 131 Chapter 1 - ADO.NET Basics RowState property, 99 Chapter 2 - Data Components in Visual RowUpdated Event Handler (code Studio listing),.NET 218 Chapter RowUpdating 3 - ADO.NET andinRowUpdated Disconnectedevents, Environments 216,218-219 RowUpdating Event Handler (code listing), 218-219 Chapter 4 - ADO.NET in Connected Environments Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Index S


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Save Image Button Click Event Handler (code listing), 835–837 interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Save method, 253 ADO.NET.

Savepoints defined, 198 and Commit, 204–206 TableRollback of Contents in Sql Data Provider, Using (code Solutions listing), 205–206 Applied ADO.NET—Building Data-Driven Introduction Saving

Chapter - ADO.NET Basics data1 and using GetChanges, 777 Chapter DataSet 2 - Data DataComponents to XML Document in Visual (code Studio listing), .NET 271–272

DataTable in XMLinDocuments (code listing), 114 Chapter 3 - ADO.NET Disconnected Environments documents (DOM), Chapter 4 - ADO.NET in 253 Connected Environments Only5 Modified Rows of DataSet (code listing), 193 Chapter - Handling ADO.NET Events Updated Data in a Data From a DataGrid Control (code listing), 343–344 Chapter 6 - Integrating XML Source with ADO.NET Chapter scalability 7 -and Data performance Binding and (ADO.NET), Windows Forms 11 Data-Bound Controls Chapter 8 - Constraints and Data Relations schemas Chapter 9 - ADO.NET Handling database, defined,Exception 779 Chapter 10See - Working withintegration the ODBC .NET Data Provider XML. under XML with ADO.NET Chapter 11 - Stored Procedures and Views

Search Button Click Event Handler (code listing), 341–342


SearchButtonClick Method (code listing), 112–113


searching Chapter 14 - Developing Database Web Applications using ASP.NET a DataGrid, 338–342 Chapter 15 - Using ADO.NET in Xml Web Services using DataView, Chapter 16DataTable - ASP.NET and Server Controls 339–341 and Data Binding using SELECT statement, 339 using XPathNavigator, 276–277


Second19Normal Form (2 NF), 782–784 Considerations and Data Binding Chapter - Mapped Objects: Performance Chapter 20 DISTINCT - COM Interoperability and ADO.NET SELECT and duplicates, 827–828 Chapter 21 statements - Messaging SELECT Chapter 22 - SQL Server and ADO.NET: Notes on listing), Performance Executing Using OleDbDataAdapter (code 167–168 Appendix A - Relational Some Basic Concepts retrieving data with,Databases: 777 Appendix B - Commonly searching with, 339Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions SELECT TOP SQL statement, paging with, 816 IndexSELECT...FOR XML clauses, 809–810

SELECT...LIKE SQL statement, 194 List of Figures using, 796–802 List of Tables List of Listings SelectCommand, 184 List of Sidebars

Selecting Distinct Rows From DataBase Table (code listing), 827–828 SelectVideosCheckedIn Query, Optimized Version (code listing), 763–764 SelectVideosCheckedOutToUser (code listing), 665 Send Message Click Event Handler (code listing), 618 Send method (MessageQueue), 740–741 Sending and Receiving Transactional Messages (code listing), 749–750 Sending Messages to a Queue (code listing), 743 serialization, defined, 236 server controls in ASP.NET. SeeASP.NET server controls and data binding

server cubes, OLAP, 718


Server Explorer, 34–36 ISBN:1590590732 by Mahesh Chand and David Talbot adding new connection, 35 Apress © 2003 (928 pages) available views, 408 This text provides extensive coverage of ADO.NET technology creating DataAdapters with, 41 internals, namespaces, classes, and including ADO.NET expanding databases with, interfaces, and54 takes a comprehensive look at XML and36 classes, and how to integrate both with managing andnamespaces viewing data, ADO.NET.

server-side controls, ASP.NET. SeeASP.NET server-side controls service components (OLE DB), 5–6 Table of Contents

session pooling, 146


severity level errors, 368–369 Introduction Chapter simple 1and- complex ADO.NET data Basics binding, 288,538 Chapter - Data Components in Visual Studio .NET Simple2Exception Handling Block (code listing), 361 Chapter 3


simple Web Forms controls, data binding in, 540–562 - ADO.NET in Connected Environments Button control, 540–541 Chapter 5 - Handling ADO.NET Events Calendar control, 542–545 Chapter 6 - Integrating XML558–560 with ADO.NET DropDownList control, Chapter 7 Data Binding and ListBox control, 556–558 Windows Forms Data-Bound Controls Chapter 8 - Constraints and Data Relations ListControl class, 555–556 Chapter 9 - ADO.NET Repeater control, Exception 552–555 Handling Chapter 10 - Working with the ODBC .NET Data Provider templates, Web server control. Seetemplates, Web server control templates Chapter TextBox, 11 - Stored ButtonProcedures and Imageand controls, Views 560–562 Chapter 4

Chapter 12 - data-bound Oracle, SQLXML, and Other single-item controls, 488 .NET Data Providers Chapter 13 - Developing a Custom Data Provider

single object-oriented API, 9–10


Skip Method, Using (code listing), 244 Services Chapter 15 - Using ADO.NET in Xml Web SOAP (Simple Object Access Protocol), 517–518 Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17Explorer, - Building525, Real-World Web Applications Solution 527 Chapter 18 - Object-Relational Mapping in .NET

sorting custom in DataGrid, 334 Chapter - COM Interoperability and ADO.NET Data20Using Select Method (code listing), 113–114 Chapter 21 Messaging in a DataGrid Control (code listing), 606–607 Chapter 22 - SQLControl's Server and ADO.NET: Notes on Performance a DataGrid Columns (code listing), 334 Appendix A Relational Databases: Some Basic Concepts default sorting order, 605 Appendix B - Commonly Used SQL605–607 Statements and searching in DataGrid, Appendix Sort property C - ADO.NET (DataView), Frequently 131 Asked Questions


Index sp_executesql to Execute Database Query (code listing), 765 List of Figures

SQL Server and ADO.NET, 753–778 ADO.NET performance issues, 769–777 List of Listings Connection strings and pooling, 777 List of Sidebars data providers, selecting, 769–770 designer vs. manual development, 775 generic data access components, writing, 770–775 GetChanges method and saving data, 777 retrieving data, 775–777 stored procedures vs. SQL commands, 777 updating data sources, 776 code listings Generic Data Access Class, 771–773 Generic Data Access Class, Using, 774–775 Query from SelectVideosCheckedIn, Not Optimized, 762–763 SelectVideosCheckedIn Query, Optimized Version, 763–764 List of Tables

sp_executesql to Execute a Database Query, 765 Applied ADO.NET: Building Data-Driven Solutions User-Defined Variables, 773–774 ISBN:1590590732 by Mahesh Chand and David Talbot SQL Server performance, improving, 753–769 Apress © 2003 (928 pages) columns, selecting for indexing, 757–758 This text providesdangers extensive database design slippage, of,coverage 768–769of ADO.NET technology including ADO.NET internals, namespaces, classes, and database pages, checking size of, 767–768 interfaces, and takes a comprehensive look at XML denormalization, 768 and classes, and how to integrate both with namespaces indexes, using, 753–757 ADO.NET. locks, avoiding, 766 SQL Server Profiler, 758–762 Table of stored Contents procedure recompilation, 765 Applied ADO.NET—Building Data-Driven Solutions tables, optimal design of, 766–767 Introduction Transact-SQL queries, optimizing, 762–764 Chapter 1

- ADO.NET Basics

SQL (Structured Query Language) Chapter 2 - Data Components in Visual Studio .NET Access Group (SAG), 3 Chapter 3 - ADO.NET in Disconnected Environments commands, executing (Oracle .NET data provider), 418–421 Chapter 4 ADO.NET in Connected Environments data provider Chapter classes, 5 - Handling 138 ADO.NET Events Chapter Sql 6 -Data Integrating XML with Savepoints ADO.NET in (code listing), 205–206 Provider, Using Chapter transaction 7 - Data Binding and Windows Forms Data-Bound Controls methods in, 204–205 Chapter DataAdapters, 8 - Constraints 40–51and Data Relations Adapter Configuration Wizard. SeeData Adapter Configuration Wizard Chapter Data 9 - ADO.NET Exception Handling Explorer, DataAdapters with, 41 Chapter Server 10 - Working withcreating the ODBC .NET Data Provider injection, 405–406, 810 Chapter 11 - Stored Procedures and Views queries Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers batches of, 164 a Custom Data Provider Chapter 13 - Developing defined, 7 Chapter 14 - Developing Database Web Applications using ASP.NET executing, 504 Chapter 15 - Using ADO.NET in Xml Web Services SQL INSERT, UPDATE, DELETE Queries, Constructing (code listing), 421 Chapter 16 - ASP.NET Server Controls and Data Binding types, selecting, 42–43 Chapter 17 - Building Real-World Web Applications SQL Server Chapter 18 - Object-Relational Mapping in .NET Analysis Server in 2000, 718 Chapter Enterprise 19 - Mapped Objects:84, Performance Considerations and Data Binding Manager, 393 Chapter error 20 - COM Interoperability and ADO.NET logs, 370 Chapter errors, 21 - Messaging recognizing, 368–369 Chapter INSERT 22 - SQLcommand, Server and 186 ADO.NET: Notes on Performance AppendixProfiler, A - Relational Databases: Some Basic Concepts 758–762 AppendixProvider B - Commonly Components, Used SQL Added Statements (code listing), 48–49 Data From (codeAsked listing), 371–373 AppendixReading C - ADO.NET Frequently Questions Index storing data in, 757 version 2000, 430,666 List of Figures SQL statements List of Tables to add and remove constraints, 352–353 List of Listings ALTER TABLE, 353 List of Sidebars commonly used, 793–810 CREATE TABLE, 353,803 DELETE,534,802–803 DROP TABLE, 803–804 executing. See under Command objects generating, 43 INSERT,805 inserting dates in, 814 joins and aliases, 806–807 reading from two or more tables with, 190 SELECT,796–802 SELECT...FOR XML clauses, 809–810 stored procedures and, 398

TRUNCATE TABLE, 804 Applied ADO.NET: Building Data-Driven Solutions UPDATE,534, 802 ISBN:1590590732 Mahesh Chand and David Talbot views and,by 807–809 Apress © 2003 (928 pages) SqlCommand Properties, Setting and Getting (code listing), 151 text provides extensive coverage ADO.NET SqlCommandThis to Read Data from Database (code of listing), 153technology including ADO.NET internals, namespaces, classes, and SqlCommandBuilder, 182–184 interfaces, and takes a comprehensive look at XML SqlCommandBuilder Class, listing), namespaces andCreating classes, and and Using how to(code integrate both183–184 with SqlConnectionADO.NET. class, 38,139 SqlConnection objects, creating (code listing), 139–140 SqlDataAdapter Table of class Contents properties, 168–169 Applied ADO.NET—Building Data-Driven Solutions Event Handler Bodies (code listing), 217 Introduction Instances, Creating (code listing), 167 Chapter Properties, 1 - ADO.NET Basics Using (code listing), 169 Chapter 2 - Data Components in Visual Studio 373–374 .NET SqlError and SqlErrorCollection classes, Chapter SqlException 3 - ADO.NET class, in 371–373 Disconnected Environments SqlParameter Chapter 4 - ADO.NET in Connected Environments properties, 185–187 Chapter class 5 - Handling ADO.NET Events (code listing), 177 Chapter Creating 6 - Integrating XML with ADO.NET SqlTransaction, Executing MultipleForms SQL Queries Using (code listing), 207–208 Chapter 7 - Data Binding and Windows Data-Bound Controls Chapter SQLXML 8 and - Constraints SQL XMLand .NET Data data Relations providers, 426–435

code Chapter 9 listings - ADO.NET Exception Handling Using, 429 .NET Data Provider Chapter SqlXmlAdapter, 10 - Working with the ODBC to Execute Commands, 433–435 Chapter SqlXmlCommand 11 - Stored Procedures and Views fundamentals, Chapter 12 - Oracle,426–427 SQLXML, and Other .NET Data Providers SqlXmlAdapter object, 428–429 Chapter 13 - Developing a Custom Data Provider

SqlXmlCommand object, 430–435 applied,432–435 Chapter 15 - Using ADO.NET in Xml Web Services methods,430–431 Chapter 16 - ASP.NET Server Controls and Data Binding properties,431–432 Chapter 17 - Building Real-World Web Applications SqlXmlParameter object, 429 Chapter 18 - Object-Relational Mapping in .NET FOR XML keyword, 427–428



StateChange event, 211–212


static cursors, 786 Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance stored procedures Appendix calling, A -155–157 Relational Databases: Some Basic Concepts

codeBlistings Appendix - Commonly Used SQL Statements Stored Procedure, 404Questions AppendixAddCat1 C - ADO.NET Frequently Asked Calling Stored Procedure Using SqlCommand, 155 Executing and Reading Results of Stored Procedure, 156–157 List of Figures Executing Stored Procedures with Output Parameter, 404–405 List of Tables Executing the mySP Stored Procedure Using SQL Data Provider, 400–401 List of Listings GetBlockedCategory Stored Procedure, 692–693 List of Sidebars Incremental Lazy Loading Stored Procedure, 701 Parameters, Using in Stored Procedures, 402–404 Sales by Year Stored Procedure in Northwind Database (code listing), 156 Stored Procedure Results Output, Adding Subtotal Listing to, 157 creating,393–397 executing from VS .NET, 397–399 executing programmatically, 399–405 logic in, 665–666 recompilation, avoiding excessive, 765 vs. SQL commands, 777 SQL injection, 405–406 and views, 393–411 Index

storing data in SQL Server, 757


strings, connection. Seeconnection strings by Mahesh Chand and David Talbot structured exceptions (VB .NET), Apress © 2003 (928 359 pages)

ISBN:1590590732

This text584–586 provides extensive coverage of ADO.NET technology styles, setting DataGrid, including ADO.NET internals, namespaces, classes, and

stylesheets,260–261 interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with SXPD add-on, 426 ADO.NET.

system queues, 725–726 system stored procedures, 393

Table of Contents

System.Data Exception classes, 366–368 Applied ADO.NET—Building Data-Driven Solutions Introduction System.Data namespace, 13,77,81–82,138 Chapter 1 - ADO.NET Basics System.Data.Common namespace, 77–78,82–83,138 Chapter 2 - Data Components in Visual Studio .NET

System.Data.OleDb namespace, 78–79

Chapter 3


System.Data.OracleClient namespace, 415 Chapter 4 - ADO.NET in Connected Environments System.Data.SqlClient namespace, Chapter 5 - Handling ADO.NET Events 214 Chapter 6 - Integrating XML with ADO.NET System.Data.SqlTypes namespace, 78–79 Chapter 7


Chapter 8


SystemException class, 366

System.Messaging namespace, 727–728 - ADO.NET Exception Handling

Chapter 9

System.Runtime.InteropServices 710 Chapter 10 - Working with the ODBCnamespace, .NET Data Provider Chapter 11 - Storednamespace, Procedures and Views System.SqlClient 137–139 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

System.Web namespace, 483–484


System.Web.Services namespace, 485,518


System.Web.UI 484,Web 539,540 Chapter 15 - Usingnamespace, ADO.NET in Xml Services Chapter 16 - ASP.NET Server Controls and Data Binding System.Web.UI.HtmlControls namespace, 484 Chapter 17 - Building Real-Worldnamespace, Web Applications System.Web.UI.WebControls 484 Chapter 18 - Object-Relational Mapping in .NET

System.Xml namespace, 226,234–235,238,261,431


System.Xml.Schema namespace, Chapter 20 - COM Interoperability and235 ADO.NET Chapter System.Xml.Serialization 21 - Messaging namespace, 236 Chapter 22 - SQL Server and ADO.NET: System.Xml.XPath namespace, 236 Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

System.Xml.Xsl namespace, 236

Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Index T


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and tables interfaces, and takes a comprehensive look at XML Adding Records to Using INSERT SQLand Statement (code listing), 159 namespaces and classes, how to integrate both with column mapping and, 178-181 ADO.NET.

creating relationship between, 60-61 Creating Using DataTable and DataColumn (code listing), 91-92 Tabledefined, of Contents 779 Applied ADO.NET—Building Data-Driven Solutions designing for optimal performance, 766-767 Introduction loading detail when master is loaded, 703-704 Chapter 1 - ADO.NET mappings, 45-46 Basics Chapter 2 - Data Components in Visual Studio .NET schema, obtaining using Command object, 811 Chapter SQL3 statement - ADO.NET to in read Disconnected two or more, Environments 190 TableDirect, using, Chapter 4 - ADO.NET in157-158 Connected Environments TableItemStyle properties, Chapter 5 - Handlingclass ADO.NET Events585 TableMappings property, 178-180 Chapter 6 - Integrating XML with ADO.NET Tables 124 and Windows Forms Data-Bound Controls Chapter 7 -property, Data Binding Chapter templates 8 - Constraints and Data Relations

Adding a DataList ControlHandling (code listing), 549 Chapter 9 -to ADO.NET Exception Applying on a Repeater (code listing), 546-547 Chapter 10 - Working with theControl ODBC .NET Data Provider DataGrid control, using withand template Chapter 11 - Stored Procedures Views columns, 594-598 Template Columns in a DataGrid (code listing), 596-598 Chapter 12 - Oracle, SQLXML, and OtherControl .NET Data Providers Template Columns,aUsing (code 595-596 Chapter 13 - Developing Custom Datalisting), Provider

Templates of a DataList Control, Adding Formatting to (code listing), 550-551 Web server control templates, 546-552 Chapter 15 - Using ADO.NET in Xml Web Services basics,546-547 Chapter 16 - ASP.NET Server Controls and Data Binding controls supporting templates, 548 Chapter 17 - Building Real-World Web Applications form designer, creating with, 551 Chapter 18 - Object-Relational Mapping in .NET HTML View, creating with, 549-551 Chapter Repeater 19 - Mapped Objects: Performance control support of, 552 Considerations and Data Binding Chapter types 20 - COM Interoperability and ADO.NET of, 547-548 Chapter working 21 - Messaging with programmatically, 551-552 Chapter 14 - Developing Database Web Applications using ASP.NET


text file databases, 382-388 accessing text files, 385-388 Appendix B - Commonly UsedtoSQL exporting Access table textStatements file, 383-385

Appendix A - Relational Databases: Some Basic Concepts Appendix C - ADO.NET Frequently Asked Questions

TextBox, Button and Image controls (Web Forms), 560-562

Index

TextDB.txt File, Accessing (code listing), 388 List of Figures List Thanks.aspx of Tables page, 513 List of ListingsShopping Cart Example (code listing), 680-681 Theoretical List of Sidebars

Third Normal Form (3 NF), 784-785 three-tier model, 663

Tlbimp.exe and Tlbexp.exe, 711-712 transactions avoiding to reduce locks, 766 class methods, 200 and concurrency, 198-200 implementing in OleDb data provider, 820-821 Isolation Levels (TILs), 788 methods in Sql data provider, 204-205 objects and classes, 17

in OleDb Data Provider (code listing), 821 Building Data-Driven Solutions Transact-SQLApplied queries,ADO.NET: optimizing, 762-764 ISBN:1590590732 by Mahesh Chand and transactional messaging, 747-750 David Talbot Apress © 2003 (928 pages) using,200-201 This text provides extensive coverage of ADO.NET technology

Transform method, 261 ADO.NET internals, namespaces, classes, and including interfaces, and takes a comprehensive look at XML Transformation and XSLT, 260-262


tree optimization,ADO.NET. 693-694

tree structures, large, 691-693 TreeView control, Microsoft, 693 Table of Contents Applied ADO.NET—Building Troelsen, Andrew, 709 Data-Driven Solutions Introduction

TRUNCATE TABLE statements, 804

Chapter 1

- ADO.NET Basics

Chapter 5


Try...Catch statements, 361-364 Chapter 2 - Data Components in Visual Studio .NET with multiple Catch statements, 363-364 Chapter 3 - ADO.NET in Disconnected Environments Try...Catch Block, Simple (code listing), 362 Chapter 4 - ADO.NET in Connected Environments Try...Catch...Finally statements, 362 Type Library Importer/Exporter, 711-712 - Integrating XML with ADO.NET

Chapter 6

typed DataSets Chapter 7 - Data Binding and Windows Forms Data-Bound Controls generating from XML schema, 272 Chapter 8 - Constraints and Data Relations and9untyped, 127-128 Chapter - ADO.NET Exception Handling in VS 47,51-54 Chapter 10.NET, - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Index U


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and UNIQUE Constraints interfaces, and takes a comprehensive look at XML Adding (code namespaces listing), 351 and classes, and how to integrate both with Creating (code listing), 348–349 ADO.NET.

defined, 345 UniqueConstraint class, 348–349

Table of Contents

Unix systems, 438


unmanaged code, 709 Introduction Chapter 1 - ADO.NET Basics unstructured exceptions (VB .NET), 359 Chapter - Data Components in Visual Studio .NET untyped2 DataSets Chapter 3 - 51 ADO.NET in Disconnected Environments defined, Chapter - ADO.NET in Connected and4typed DataSets, 127–128 Environments Chapter 5


updating - Integrating XML with ADO.NET data (ASP.NET), 506 Chapter 7 Binding and Windows Data-Bound Controls Data on- Data Update Button Click (codeForms listing), 506 Chapter - Constraints data8 sources, 776 and Data Relations Chapter 9 -and ADO.NET Exception Handling editing, deleting with DataList control, 573–581 Chapter 10 - Working with the ODBC .NET Data Provider inserting, and deleting with DataGrids, 342–344 Chapter 11 - command, Stored Procedures and Views Update 201 Chapter Update, 12 - Oracle, Delete,SQLXML, Cancel, and Other Edit Command .NET Data Handlers, Providers Adding (code listing), 572 Update, Delete, Cancel, and Edit Command Handlers Code (code listing), 573 Chapter 13 - Developing a Custom Data Provider Update method, 159, 176–178 Chapter 14 - Developing Database Web Applications using ASP.NET UPDATE statements (SQL), 802 Chapter 15 - Using ADO.NET in Xml534, Web Services UpdateCommand event handler, 577Data Binding Chapter 16 - ASP.NET Server Controls and UpdateDataSource and UpdateDataSet Methods Generated by Data Form Wizard (code listing), Chapter 17 - Building Real-World Web Applications 70–71 Chapter 18 - Object-Relational Mapping in .NET updategrams, 430 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding updates, .NET 1.1, 391 Chapter 6


User component, Video Store Application, 654–659 Chapter 21 - Messaging Chapter user controls 22 - SQL (server), Server 483 and ADO.NET: Notes on Performance Appendix A - Relational Databases: 393 Some Basic Concepts user-defined stored procedures, Appendix B - Commonly Used SQL Statements

User-Defined Variables (code listing), 773–774


User Object in User Component (code listing), 655–656 Index user List of queues, Figures 725–726 List of Tables User test case, Video Store Application, 659–661 List of Listings

UserData Object in User Component (code listing), 656–657

List of Sidebars

UserDataAccess Object in User Component (code listing), 657–659 UserTestCase Object (code listing), 660–661

Index V


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and validation controls, 482-483 interfaces, and takes a comprehensive look at XML namespaces classes, and how to integrate both with Video Store Application, basicand design, 640-665 ADO.NET. Check In/Check Out component, 663-665

Data Access Component (DAC), 648-652 data object, 643-644 Table of Contents database design, 641-643 Applied ADO.NET—Building Data-Driven Solutions dependencies, managing, 661-662 Introduction mapped object, 644-648 Chapter 1 - ADO.NET Basics User component, 654-659 Chapter 2 - Data Components in Visual Studio .NET User test case, 659-661 Chapter 3 tape - ADO.NET in Disconnected Environments video test case, building, 652-654 Chapter 4


Chapter 5


VideoCategory and Related Objects (code listing), 686-691

VideoCategory table, 685 Chapter 6 - Integrating XML with ADO.NET Chapter VideoCategoryIndexer 7 - Data Binding(code and Windows listing), 701-703 Forms Data-Bound Controls Chapter 8 - Constraints Test and Data VideoCategoryIndexer CaseRelations (code listing), 703-704 Chapter 9 - ADO.NET Exception Handling

VideoCheckInCheckOut Component, Test Case for (code listing), 671-673


VideoCheckInCheckOut Object (code listing), 667-670 Chapter 11 - Stored Procedures and Views Videos() Adding to VideoCategory Object (code listing), 695-696 Chapter 12Array, - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Component, Developing a Test Custom Data VideoTape Case forProvider (code listing), 653-654 Chapter 14 - Developing Database Web Applications using ASP.NET

VideoTape Object (code listing), 645-648


VideoTapeData Object (code listing), 643-644


VideoTapeDataAccess Object (code listing), 648-652 Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET View Source option, 48 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

View Wizard Results, 44


ViewGuestBook.aspx, Opening (code listing), 511


Viewing22Data From SQL Server Database listing), 30-31 Chapter - SQL Server and ADO.NET: Notes(code on Performance Appendix A - Relational Databases: Some Basic Concepts views,406-411 Appendix creating, B - Commonly 406-408 Used SQL Statements

executing from VSFrequently .NET, 409Asked Questions Appendix C - ADO.NET IndexFilling DataSets from multiple, 411

programmatically retrieving data from, 410 List of Figures understanding, 807-809 List of Tables List virtual of Listings table, 393 List of Sidebars VisibleMonthChanged Event (code listing), 545

Visio,84 Visual Basic .NET (VB .NET), 209,637 Visual Basic (VB) exception handling, 359 visual data components, 11 Visual Studio .NET accessing COM Library with, 710 to add server controls, 486 creating XML Web services in, 518-521 executing stored procedures from, 397-399 executing views from, 409

Integrated Development Environment (IDE). SeeIDE Applied ADO.NET: Building Data-Driven Solutions managing queues with, 731-732 ISBN:1590590732 by Mahesh Chand ODBC .NET data provider and,and 375David Talbot Apress © 2003 (928 pages) version 2003, 414 XML designer,This 277text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

Visual Studio .NET data components, interfaces, and takes a33-71 comprehensive look at XML code listings namespaces and classes, and how to integrate both with ADO.NET.From Button Click, 65 Calling DataForm1 Calling DataForm2 From Button Click, 66 Cancel All Button Click Event Handler (code listing), 71 Table of Contents DataAdapter Connection Through TableMapping, 49 Applied ADO.NET—Building Data-Driven Solutions FillDataSet Method Generated by Data Form Wizard, 69 Introduction Form's Load Event Handler, 50-51 Chapter 1 - ADO.NET Basics LoadDataSet Method Generated by Data Form Wizard, 68-69 Chapter 2 - Data Components in Visual Studio .NET Sql Server Provider Components, Added, 48-49 Chapter UpdateDataSource 3 - ADO.NET in Disconnected Environments and UpdateDataSet Methods Generated by Data Form Wizard, 70-71 Chapter 4 ADO.NET in Connected Environments connection strings, 40 Chapter 5 - Handling ADO.NET creating ADO.NET project,Events 33 Chapter 6 Integrating XML with ADO.NET data connections, 38-40 Chapter - Data Binding57-71 and Windows Forms Data-Bound Controls Data7 Form Wizard, Chapter adding 8 - Constraints items, 58 and Data Relations form from application, 65-66 Chapter calling 9 - ADO.NET Exception Handling relationship tables, Chapter creating 10 - Working with thebetween ODBC .NET Data60-61 Provider Connection, choosing, 59 Chapter Data 11 - Stored Procedures and Views 67-71and Other .NET Data Providers Chapter DataForm1 12 - Oracle, .vb, SQLXML, DataSet, choosing, 59 Chapter 13 - Developing a Custom Data Provider display style, choosing, 62-65 Chapter 14 - Developing Database Web Applications using ASP.NET displaying tables and columns, 62 Chapter 15 - Using ADO.NET in Xml Web Services MyDS.xsd,67 Chapter 16 - ASP.NET Server Controls and Data Binding project template, 58 Chapter 17 - Building Real-World Web Applications tables or views, choosing, 59-60 Chapter 18 - Object-Relational Mapping in .NET viewing output, 66 Chapter 19 - Mapped Objects:components, Performance 51-57 Considerations and Data Binding DataSet and DataView Chapter typed 20 - COM Interoperability and ADO.NET DataSets in VS .NET, 51-54 Chapter understanding 21 - MessagingDataView, 54-57 Chapter 22 - SQL Server fundamentals, 37-38and ADO.NET: Notes on Performance Appendix A Relational Databases: Some Basic Concepts Server Explorer, 34-36 Appendixadding B - Commonly new connection, Used SQL35 Statements and Frequently viewing data, 36 Questions Appendixmanaging C - ADO.NET Asked IndexSQL DataAdapters, 40-51 Data Adapter Configuration Wizard. SeeData Adapter Configuration Wizard List of Figures Server Explorer, creating DataAdapters with, 41 List of Tables List of Listings List of Sidebars

Index W


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and WeakCache Object (code listing), 707–708 interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Web applications ADO.NET. defined, 468

using ASP.NET. SeeASP.NET for database Web applications Webof applications, Table Contents building, 609–636 code listings Applied ADO.NET—Building Data-Driven Solutions Button Click Event Handlers, 614–615 Introduction HTML View, 624–627 Chapter DisplayData.aspx 1 - ADO.NET Basics Button Click Event 620,.NET 623 Chapter Done 2 - Data Components in Handler, Visual Studio

FillDataGrid and Page_Load Methods, 627,629 - ADO.NET in Disconnected Environments FillPartialData Method, 628 Chapter 4 - ADO.NET in Connected Environments Login Button Click Event Handler Code, 613 Chapter 5 - Handling ADO.NET Events Post Job Button Click Event Handler, 619 Chapter 6 - Integrating XML with ADO.NET Post Resume Button Click Event Handler, 622–623 Chapter 7 - Data Binding and Windows Forms Data-Bound Controls Post Resume Page, Adding Options to, 621–622 Chapter Register.aspx 8 - Constraints and Data Code, 616 Relations Chapter Resumes.aspx 9 - ADO.NET Exception Handling HTML View, 630–632 Chapter Send 10 - Working with the ODBC .NET Data618 Provider Message Click Event Handler, Chapter 11 Stored Procedures and Views database schema, 610–611 Chapter 12 -Job Oracle, SQLXML, and Other .NET Data Providers Online Board Application, developing, 611–635 Chapter Contact.aspx 13 - Developing page, a Custom 617–618 Data Provider and Resumes.aspx pages, 623–632 Chapter DisplayData.aspx 14 - Developing Database Web Applications using ASP.NET page, 632–633 Chapter dnjHeader.aspx 15 - Using ADO.NET in Xml Web Services Chapter improving/modifying 16 - ASP.NET Server application, Controls and635–636 Data Binding page, 612–615 Chapter Login.aspx 17 - Building Real-World Web Applications page, 618–620 Chapter PostJob.aspx 18 - Object-Relational Mapping in .NET PostResume.aspx page, 620–623 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Register.aspx page, 615–616 Chapter 20 - COM Interoperability and ADO.NET running the application, 633–635 Chapter 21 - Messaging specifications, 609–610 Chapter 3


Web controls Appendix A - Relational Databases: Some Basic Concepts adding to Web Forms (ASP.NET), 472–473 MyGuestBook.aspx,508 Appendix C - ADO.NET Frequently Asked Questions properties, setting (ASP.NET), 474–475 Index ViewGuestBook.aspx, 511 Appendix B - Commonly Used SQL Statements

List of Figures

Web Forms List of Tables

adding, editing, and deleting in, 502–504 adding server-side controls to, 485–487 List of Sidebars controls,480,485 defined, 468 guest book, adding to, 511–514 List of Listings

Web References Wizard, 528 Web server controls, 481–482 Web-service-based data provider, 437 Web services creating consumer, 524–534 adding data to database, 529–533 adding functionality, 534 defined, 468

WebService and WebMethod Attributes, Adding Descriptions to (code listing), 522–524 ADO.NET: Building Data-Driven Solutions XML.SeeXMLApplied Web services by Mahesh Chand and David Talbot

ISBN:1590590732

Web sites Apress © 2003 (928 pages) Apress,297 This text provides extensive coverage of ADO.NET technology C# Corner discussion 811 namespaces, classes, and including newsgroup, ADO.NET internals, C# Corner's XML.NET 233, 297 interfaces,section, and takes a comprehensive look at XML namespaces classes, 845 and how to integrate both with connection strings for dataand providers, ADO.NET. forms info, 786 database design/normal DBTools download, 381 Duwamish7 demo application download, 639 Table of Contents locking and concurrency levels information, 791 Applied ADO.NET—Building Data-Driven Solutions Microsoft,376 Introduction Microsoft downloads, 414 Chapter 1 - ADO.NET Basics Microsoft TreeView control, 693 Chapter 2 - Data Components in Visual Studio .NET MySQL database/tools download, 380 Chapter 3 databases, - ADO.NET in Disconnected Environments object 639 Chapter 4 ADO.NET in ODBC drivers, 381 Connected Environments Chapter 5 -data Handling ADO.NET Events Oracle provider article, 414 Chapter 6 Integrating XML with ADO.NET OraDirect.NET download, 414 Chapter 7 Data Binding and Windows Forms Data-Bound Controls relational databases online resources, 792 Chapter SQL8 online - Constraints references, and 810 Data Relations SQL9 Server performance info, 760 Chapter - ADO.NET Exception Handling SQLXML updateswith andthe downloads, 426 Chapter 10 - Working ODBC .NET Data Provider transaction processing info,and 789 Chapter 11 - Stored Procedures Views Chapter 12characters, - Oracle, SQLXML, and Other .NET Data Providers wildcard 194 Chapter 13 Registry, - Developing a Custom Data Provider Windows reading/writing to, 828–831 Chapter 14 - Developing Database Web Applications using ASP.NET

wiring protocol, 518


WriteXml 264–265 Chapter 16 method, - ASP.NET Server Controls and Data Binding Chapter WriteXml 17 Method - Building Output Real-World (codeWeb listing), Applications 266 Chapter 18 Method, - Object-Relational Mapping in 265–266 .NET WriteXml Using (code listing), Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

WriteXmlSchema method, 127,266–267


writing 21 XML items, 247–248 Chapter - Messaging WSDL 22 (Web Service Description Language), 527 Chapter - SQL Server and ADO.NET: Notes on517, Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars

Index X


ISBN:1590590732

This text provides extensive coverage of ADO.NET technology ADO.NET internals, namespaces, classes, and XML (Extensible including Markup Language), support, 8,10,12–13 interfaces, and takes a comprehensive look at XML namespaces and classes, XML integration with ADO.NET, 233–286 and how to integrate both with code listings ADO.NET.

Adding Node with Attributes, 260 Adding Nodes to Document, 256 Table of Contents Appending in XML Document Fragment, 254 Applied ADO.NET—Building Data-Driven Solutions GetAttribute of a Node, Using, 243–244 Introduction Getting Node Information, 240–241 Chapter 1 - ADO.NET Basics Getting Root Node of Document, 256 Chapter 2 - Data Components in Visual Studio .NET Getting XML Node Information, 240 Chapter Inserting 3 - ADO.NET in Disconnected Environments XML Fragment into Document, 259 Chapter MoveToContent 4 - ADO.NET in Method, Connected Environments Using, 243 Chapter Moving 5 - Handling to RootADO.NET and FirstEvents Child Nodes Using XPathNavigator, 274–275 Chapter Output 6 - Integrating XML with ADO.NET of XmlWriterSample.vb Class, 249–250 Chapter Reading 7 - Dataan Binding and 239 Windows Forms Data-Bound Controls XML file, Chapter RemoveAll 8 - Constraints for books.xml, and Data Relations Calling, 258 All Items of a Handling Node, 257 Chapter Removing 9 - ADO.NET Exception Calling, 258 .NET Data Provider Chapter ReplaceChild, 10 - Working with the ODBC DataSet Data toand XML Document, 271–272 Chapter Saving 11 - Stored Procedures Views Using, 244 Chapter Skip 12 - Method, Oracle, SQLXML, and Other .NET Data Providers method Output, Data 266 Provider Chapter WriteXml 13 - Developing a Custom WriteXml method, Using, 265–266 Chapter 14 - Developing Database Web Applications using ASP.NET WriteXmlSchema Method, Using, 267 Chapter 15 - Using ADO.NET in Xml Web Services XML Schema Generated for Database Table, 284–285 Chapter 16 - ASP.NET Server Controls and Data Binding XmlConvert Class, Using, 251 Chapter 17 - Building Real-World Web Applications XmlDataDocumentSample.vb,270 Chapter 18 - Object-Relational Mapping in .NET XmlDocumentFragment Sample, 254 Chapter XmlWriter 19 - Mapped Objects:248–249 Performance Considerations and Data Binding Example, Chapter XmlWriterSample.vb 20 - COM Interoperability andOutput ADO.NET Class, of, 249–250 Chapter XPathIterator 21 - Messaging and Select, 276–277 Chapter XPathNavigator, 22 - SQL Server and ADO.NET: Notes on Performance Reading Document Using, 275–276 AppendixXSL A - Transformation, Relational Databases: Some Basic Concepts 262 Appendix DOMB(Document - CommonlyObject Used SQL Model) Statements implementation, 251–260 attributes to nodes, 259–260 Appendixadding C - ADO.NET Frequently Asked Questions Index fragments, inserting into XML document, 259 saving documents, 253 List of Figures XmlDocument class, 252–253 List of Tables XmlDocumentFragment class, 253–254 List of Listings XmlElement class, 254–259 List of Sidebars XmlNode class, 252 navigating in XML, 272–277 searching using XPathNavigator, 276–277 XPathNavigator class, 273 XPathNavigator move methods, 274–276 .Net Framework and XML, 233–238 document classes, 234 DOM interfaces, 237 reader and writer classes, 234 System.Xml namespace, 234–235 System.Xml namespace reference, adding, 238 System.Xml.Schema namespace, 235

System.Xml.Serialization namespace, 236 Applied ADO.NET: Building Data-Driven Solutions System.Xml.XPath namespace, 236 ISBN:1590590732 by Mahesh Chand and David Talbot System.Xml.Xsl namespace, 236 Apress © 2003 (928 pages) XML .NET architecture, 237–238 This text 235, provides XmlConvert class, 251 extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and reading XML, 238–246 interfaces, and takes a comprehensive look at XML closing document, 245–246 namespaces and classes, and how to integrate both with fundamentals, 238–239 ADO.NET. GetAttributes of a node, 243–244 getting node information, 239–242 Table of moving Contents to content node, 242–243 Applied ADO.NET—Building Solutions searching for node,Data-Driven 244 Introduction Transformation and XSLT, 260–262 Chapter example, 1 - ADO.NET Basics 261–262 Chapter Transform 2 - Data Components method, 261in Visual Studio .NET Chapter XML3 and - ADO.NET ADO.NET, in Disconnected using together, Environments 262–272 XMLindata in DataSet format, 270 Chapter displaying 4 - ADO.NET Connected Environments XML using DataSet, 262–264 Chapter reading 5 - Handling ADO.NET Events data fromXML DataSet to XML, 271–272 Chapter saving 6 - Integrating with ADO.NET XML using and DataSet, 264–267 Chapter writing 7 - Data Binding Windows Forms Data-Bound Controls XmlDataDocument and DataSet objects, 272 Chapter 8 - Constraints and Data Relations XmlDataDocument and XML, 267–269 Chapter 9 - ADO.NET Exception Handling XML schemas, 277–286 Chapter 10 - Working with the ODBC .NET Data Provider adding schema from database objects, 283–285 Chapter 11 - Stored Procedures and Views generating new schemas, 277–283 Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers generating typed DataSet from a schema, 285–286 Chapter 13 - Developing a Custom Data Provider XmlConvert class, 235,251 Chapter 14 - Developing Database Web Applications using ASP.NET XmlWriter classes, 246–250 Chapter Close 15 - Using ADO.NET method, 250 in Xml Web Services Chapter properties, 16 - ASP.NET Server Controls and Data Binding setting, 247 Chapter writing 17 - Building Real-World Web Applications XML items, 247–248 Chapter XmlWriter 18 - Object-Relational Mapping in .NET applied, 248–250 Chapter 19 -services, Mapped Objects: XML Web 517–535Performance Considerations and Data Binding Chapter 20 - and COMtesting, Interoperability building 521–524and ADO.NET Chapter 21listings - Messaging code Chapter Button-Click 22 - SQL Server andHandler ADO.NET: onOrder Performance Event for Notes Calling Retrieval Web Service, 528–529 AppendixClient A - Relational Databases: Some Basic Concepts Event Handler For Executing Web Service, 533 AppendixExecuteQuery B - CommonlyMethod, Used SQL 534 Statements

Method, 521 AppendixGetOrdersFromDatabase C - ADO.NET Frequently Asked Questions Index

Populating an Order in a Database, Web Service Method for, 530–531

WebService and WebMethod Attributes, Adding Descriptions to, 522–524 List of Figures components of, 517–518 List of Tables .NET Framework Library and, 518 List of Listings

VS .NET, creating in, 518–521 Web service consumer, creating, 524–534 adding data to database, 529–533 adding functionality, 534

List of Sidebars

XmlDataDocument Event Handling Example (code listing), 227–228 events,226–229 XmlNode class, 234,252 XmlNodeChangingEventHandler method, 227 XmlNodeType enumeration members, 242 XmlReader

class properties and methods, 245–246 Applied ADO.NET: Building Data-Driven Solutions classes,238–239 ISBN:1590590732 Mahesh Chand and David Talbot retrieving databywith, 775–776 Apress © 2003 (928 pages)

XmlReadMode members, 263


XmlWriteMode members, including ADO.NET 265 internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

XmlWriter classes, 246–250 and classes, and how to integrate both with namespaces ADO.NET. Xpath classes, 236, 238 XPathNavigator methods, 274–276 Tablemove of Contents searching with, 276–277 Applied ADO.NET—Building Data-Driven Solutions using, 273 Introduction Chapter XSL (Extensible 1 - ADO.NET Stylesheet Basics Language), 260–261 Chapter 2 -Transformation, Data Components in Visual Studio .NET XSLT and 236, 260–262 Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions List of Figures ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

Chapter 1: This ADO.NET Basics text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Figure 1-1: ODBC architecture


Figure 1-2: DAO model

Figure 1-3: OLE DB model

Table of Contents

Applied ADO.NET—Building Data-Driven Solutions Figure 1-4: The ADO.NET components model Introduction

Figure The relationship between Connection,DataAdpater, and a data source Chapter 1 - 1-5: ADO.NET Basics Chapter 2


Chapter 3


Figure 1-6: The relationship between the Command object and the Connection object

Chapter 4 - 1-7: ADO.NET in Connected Environments Figure Creating a transaction from a Connection object Chapter 5 - Handling ADO.NET Events Chapter Figure 6 - 1-8: Integrating The relationship XML with ADO.NET between DataAdapter and Command Chapter 7


Figure Creatingand a DataReader Chapter 8 - 1-9: Constraints Data Relations from a Command object Chapter 9


Figure 1-10: The relationship between DataAdapter and CommandBuilder


Chapter 11 - 1-11: StoredThe Procedures and between Views Figure relationship DataAdapter and DataSet Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Figure The relationship between classes in a DataSet Chapter 13 - 1-12: Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Figure 1-13: The relationship between DataSet and DataView objects


Chapter 16 - 1-14: ASP.NET Server Controls and Data Binding Figure Adding a reference to the System.Data.dll assembly Chapter 17 - Building Real-World Web Applications

Figure Displaying data on the console using DataReader Chapter 18 - 1-15: Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Figure 1-16: Output of the ADO.NET application in a DataGrid control


Chapter 2: Data Components in Visual Studio .NET


Figure Table Mappings dialog box Appendix B - 2-1: Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Figure 2-2: Previewing data for the DataAdapter

Index

List ofFigure Figures2-3: Output of the Employee data to a DataGrid control List of Tables List ofFigure Listings 2-4: A DataSet's Properties window showing a typed DataSet List of Sidebars

Figure 2-5: Creating a typed DataSet from the Add New Item window Figure 2-6: Empty Dataset1.xsd in the VS .NET IDE Figure 2-7: Design view of the DataSet's XML schema Figure 2-8:DataView Properties window Figure 2-9: Sorted and filtered data in a DataGrid Figure 2-10: Adding a Data Form Wizard Figure 2-11: Choosing tables and views

Figure 2-12: Applied SelectingADO.NET: Customers as the parent and Orders as the child table to create the Building Data-Driven Solutions CustOrderRelation relationship ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

Figure 2-13: Choosing columns to display on the Data Form Wizard

This text provides extensive coverage of ADO.NET technology namespaces, classes, and Figure 2-14: including ChoosingADO.NET betweeninternals, a grid and individual controls on the Data Form Wizard interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Figure 2-15: ADO.NET. Grid DataForm output

Figure 2-16: The Single Record in Individual Controls option Table of Contents

Figure 2-17: Data Form Wizard-generated form for the Single Record in Individual Controls option


Chapter 3: ADO.NET in Disconnected Environments - ADO.NET Basics

Chapter 1 Chapter 2


Figure ADO.NET architecture Chapter 3 - 3-1: ADO.NET in Disconnected Environments Chapter 4


Chapter 5


Figure 3-2: The System.Data namespace class hierarchy

Chapter 6 - 3-3: Integrating XML with ADO.NET namespace hierarchy Figure The System.Data.Common Chapter 7 - Data Binding and Windows Forms Data-Bound Controls

Figure The System.Data.SqlTypes namespace hierarchy Chapter 8 - 3-4: Constraints and Data Relations Chapter 9


Figure 3-5: The System.Data.OleDb namespace hierarchy


Chapter 11 - 3-6: Stored Proceduresbetween and Views Figure Relationship the DataTable, the DataRow, and the DataColumn Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Figure The DataGrid view of an empty DataTable Chapter 13 - 3-7: Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Figure 3-8: A DataTable with three rows

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - 3-9: ASP.NET Server Controls Data Binding Figure A DataGrid with dataand relations Chapter 17 - Building Real-World Web Applications

Figure Orders record for Customers Chapter 18 - 3-10: Object-Relational Mapping in .NET id 1001 Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Figure 3-11: Add, delete, sort, and search operations in a DataTable


Chapter 21 - 3-12: Messaging Figure Adding rows to the DataTable Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix Figure A - 3-13: Relational Deleting Databases: rows from Some theBasic DataTable Concepts Appendix B - Commonly Used SQL Statements

Figure Result of clicking the Questions Search button for Name="Amy" Appendix C - 3-14: ADO.NET Frequently Asked Index

Figure 3-15: Relationship between the DataSet,DataTable, and DataView

List of Figures

List ofFigure Tables3-16: The relationship between DataSet, DataAdapter, and DataView objects List of Listings

3-17: Attaching DataTables to a DataSet List ofFigure Sidebars

Chapter 4: ADO.NET in Connected Environments Figure 4-1: A generic data provider model Figure 4-2: Output of the Customers table from the DataReader Figure 4-3: Creating a Windows Forms application and adding controls to the form Figure 4-4: Filling data from an Access database to a DataGrid control using OleDbDataAdapter Figure 4-5: Filling data from a SQL Server database to a DataGrid control using SqlDataAdapter

Figure 4-6: Column Appliedmapping ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

Figure 4-7: Default multiple views application

ISBN:1590590732

This text provides coverage of ADO.NET technology Figure 4-8: Multiple views with extensive different filter and sorting criteria including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Chapter 5: Handling ADO.NET Events

Figure 5-1: Event handler and event argument classes defined in the System.Data namespace Table of Contents

Figure 5-2: OleDb data provider event handler and event arguments


Introduction Figure 5-3: Output of the Open button click Chapter 1 - ADO.NET Basics

Figure of the in Close button click Chapter 2 - 5-4: DataOutput Components Visual Studio .NET Chapter 3


- ADO.NET in Connected Environments Chapter 6: Integrating XML with ADO.NET

Chapter 4 Chapter 5


Chapter 6 - 6-1: Integrating XMLarchitecture with ADO.NET Figure XML .NET Chapter 7


Figure XmlReader and Relations its derived classes Chapter 8 - 6-2: Constraints and Data Chapter 9


Figure 6-3: The XmlWriter class and its derived classes


Chapter 11 - 6-4: Stored and Views Figure TheProcedures XmlElement class inheritance Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Figure The XSL transformation Chapter 13 - 6-5: Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Figure 6-6: The XmlDataDocument class inheritance


Chapter 16 - 6-7: ASP.NET Server Binding Figure Reading andControls writing and dataData using XmlDataDocument Chapter 17 - Building Real-World Web Applications

Figure The XML designer Chapter 18 - 6-8: Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Figure 6-9: The XML schema Toolbox

Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - 6-10: Messaging Figure Adding a schema element and its type Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Figure Adding a new bookstore Appendix A - 6-11: Relational Databases: Some Basic element Concepts Appendix B - Commonly Used SQL Statements

Figure 6-12: A complexType item

Appendix C - ADO.NET Frequently Asked Questions IndexFigure 6-13: Adding other types to complexType item List of Figures List ofFigure Tables6-14: The book complexType and its elements List of Listings

Figure 6-15: The author and book complexTypes in an XML schema

List of Sidebars

Figure 6-16: Viewing the XML code for a schema Figure 6-17: XML designer–generated schema Figure 6-18: The DataSet-derived class in the Class View

Chapter 7: Data Binding and Windows Forms Data-Bound Controls Figure 7-1: Synchronization between a data source and data-bound controls Figure 7-2: Record navigation form

Figure 7-3: Record navigation system in action


by Mahesh Chand and David Talbot Figure 7-4:ListBox and ComboBox data-binding form

ISBN:1590590732


Figure 7-5: Data in ComboBox and controls This synchronization text provides extensive coverage of ListBox ADO.NET technology including ADO.NET internals, namespaces, classes, and

Figure 7-6: The DataGrid's parent items and background interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET. Figure 7-7: The DataGrid's parts

Figure 7-8:DataGrid-related style objects

Table of Contents

Applied ADO.NET—Building Data-Driven Solutions Figure 7-9: Column reshuffling form Introduction

Figure Getting a DataGrid control's column styles Chapter 1 - 7-10: ADO.NET Basics Chapter 2


Chapter 3


Figure 7-11: Pop-up menu on DataGrid right-click menu

Chapter 4 - 7-12: ADO.NET in Connected Environments Figure DataGrid navigation system Chapter 5

- Handling ADO.NET Events Figure Implementing functionality in a DataGrid control Chapter 6 - 7-13: Integrating XML withsearch ADO.NET Chapter 7


Chapter 8


Chapter 9


Figure 7-14: Filtered data after searching

Chapter 9: ADO.NET Exception Handling


Figure A system-generated error Chapter 12 - 9-1: Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

Figure 9-2: An exception-handled error message

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - 9-3: Using ADO.NET Xml Web Services Figure The custominerror message Chapter 16 - ASP.NET Server Controls and Data Binding

Figure SqlException messages for SQL Server not found Chapter 17 - 9-4: Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Figure 9-5:SqlException messages when a database table not found


Chapter 10: Working with the ODBC .NET Data Provider



Figure The output of Listing Appendix A - 10-1: Relational Databases: Some10-1 Basic Concepts Appendix B - Commonly Used SQL Statements

Figure 10-2: Export Text Wizard options

Appendix C - ADO.NET Frequently Asked Questions IndexFigure 10-3: The advanced options of the Export Text Wizard List of Figures

Figure 10-4: Delimiter options of the Export Text Wizard

List of Tables

List ofFigure Listings 10-5: Exported Employees.txt file from Nothwind.mdb List of Sidebars

Figure 10-6: Selecting the Microsoft Text Driver (*.txt, *.csv) option Figure 10-7: Setting the DSN name and description Figure 10-8: Selecting the directory and file types Figure 10-9: Defining a text file format and column settings Figure 10-10:Employees.xls data view Figure 10-11: Output of Listing 10-4

Chapter 11:Applied Stored Procedures and Views ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

Figure 11-1: Apress Viewing© available stored procedures in the Northwind database 2003 (928 pages) This text provides extensive coverage of ADO.NET technology

Figure 11-2: including Create, edit, delete, and run stored procedure options ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

Figure 11-3: namespaces Stored procedure editor and how to integrate both with and classes, ADO.NET.

Figure 11-4: Creating a stored procedure 11-5: The mySP stored procedure in the editor Table Figure of Contents Applied ADO.NET—Building Data-Driven Solutions

Figure 11-6: The mySP stored procedure listed for the Northwind database

Introduction

Chapter 1 - 11-7: ADO.NET Figure The Basics output of the mySP stored procedure in VS .NET Chapter 2 - Data Components in Visual Studio .NET

Figure Stored procedure with input parameter Chapter 3 - 11-8: ADO.NET in Disconnected Environments Chapter 4


Chapter 5


Figure 11-9: Registering a stored procedure parameter

Chapter 6 - 11-10: Integrating XML with Figure The output of ADO.NET stored procedure CustOrdersDetail Chapter 7 - Data Binding and Windows Forms Data-Bound Controls

Figure The output of stored procedure mySP Chapter 8 - 11-11: Constraints and Data Relations Chapter 9


Figure 11-12: A stored procedure with parameters

Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - 11-13: Stored Output Procedures and Views Figure of Listing 11-2


Figure Adding tables to theProvider view designer Chapter 13 - 11-14: Developing a Custom Data Chapter 14 - Developing Database Web Applications using ASP.NET

Figure 11-15: Creating a view after selecting columns from three tables


Chapter 16 - 11-16: ASP.NET Server and Data Binding Figure Saving a Controls view Chapter 17 - Building Real-World Web Applications

Figure Entering a Mapping name forinthe view Chapter 18 - 11-17: Object-Relational .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Figure 11-18: Available views in the Server Explorer


Chapter 21 - 11-19: Messaging Figure Results of the CustEmpView view after executing it from the Server Explorer Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Figure TheDatabases: output theSome CustEmpView view from a program Appendix A - 11-20: Relational Basic Concepts Appendix B - Commonly Used SQL Statements

Chapter 12: Oracle, SQLXML, and Other .NET Data Providers


List ofFigure Figures12-1: Adding a reference to System.Data.OracleClient.dll List of Tables

12-2: Adding a reference to Microsoft.Data.SqlXml.dll List ofFigure Listings List of Sidebars

Chapter 13: Developing a Custom Data Provider Figure 13-1: A Web-service-based data provider that accesses a Relational Database Management System (RDBMS) Figure 13-2: A custom data provider at a high level Figure 13-3: Data from pipeddata.txt in Notepad Figure 13-4: The output of the PipedDataProvider application

Chapter 14:Applied Developing Database WebSolutions Applications using ASP.NET ADO.NET: Building Data-Driven by Mahesh Chand and David Talbot

ISBN:1590590732

Figure 14-1: Apress The FirstWebApplication project © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology

Figure 14-2: including Default WebForm1.aspx page ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

Figure 14-3: namespaces HTML view of WebForm1.aspx and classes, and how to integrate both with ADO.NET.

Figure 14-4: An ASP.NET page's right-click options 14-5: An ASP.NET document's page properties Table Figure of Contents Applied ADO.NET—Building Data-Driven Solutions

Figure 14-6: Web Forms controls

Introduction

Chapter 1 - 14-7: ADO.NET Basics Figure WebForms1.aspx Design mode after adding Web Forms controls Chapter 2 - Data Components in Visual Studio .NET

Figure Properties window for the Web controls Chapter 3 - 14-8: ADO.NET in Disconnected Environments Chapter 4


Chapter 5


Figure 14-9: Final page of the Web application after changing some control properties

Chapter 6 - 14-10: Integrating XML with ADO.NET Figure Document Outline viewer Chapter 7


Figure HTML view of Relations the Document Outline viewer Chapter 8 - 14-11: Constraints and Data Chapter 9


Figure 14-12: Output of your first Web application


Chapter 11 - 14-13: Stored Your Procedures and Views Figure first ADO.NET Web application Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Figure An item Chapter 13 - 14-14: Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Figure 14-15: Multi-item controls

Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - 14-16: ASP.NET Server Controls and Data Binding Figure Data-bound controls Chapter 17 - Building Real-World Web Applications

Figure DataGrid Mapping properties Chapter 18 - 14-17: Object-Relational in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Figure 14-18:DataGrid's Auto Format dialog box


Chapter 21 - 14-19: Messaging Figure DataGrid general properties Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Figure DataGrid Columns properties page Appendix A - 14-20: Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Figure 14-21:DataGrid Paging properties page


IndexFigure 14-22:DataGrid Format properties page List of Figures List ofFigure Tables14-23:DataGrid Border properties page List of Listings

14-24: The final DataGrid after setting various properties List ofFigure Sidebars Figure 14-25: Viewing data in a DataGrid using the design-time data binding method Figure 14-26: Paging option in a DataGrid Figure 14-27: Adding, editing, and deleting pages Figure 14-28: Adding a new record in the Web application Figure 14-29: Updating records in a Web application Figure 14-30: Table schema of Guest table of GuestBook.mdb

Figure 14-31:MyGuestBook.aspx submission page


Mahesh Chand and David Talbot Figure 14-32:byThe ViewGuestBook.aspx page

ISBN:1590590732


Figure 14-33:This Thank pageextensive coverage of ADO.NET technology text you provides including ADO.NET internals, namespaces, classes, and

Figure 14-34:interfaces, Welcomeand to my guest book takes a comprehensive look at XML namespaces and classes, and how to integrate both with

Figure 14-35:ADO.NET. The Thanks.aspx page of the guest book Figure 14-36: My guest book entries Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Chapter 15: Using ADO.NET in Xml Web Services


- ADO.NET Basics

Chapter 2


Figure 15-1: Creating a new Web service project

Chapter 3 - 15-2: ADO.NET in Disconnected Environments Figure Initially running the Web service Service1.asmx Chapter 4

- ADO.NET in Connected Environments Figure TheADO.NET Web service after you add attributes Chapter 5 - 15-3: Handling Events Chapter 6


Chapter 7


Figure 15-4: The Order DataSet displayed by the browser in XML format

Chapter 8 - 15-5: Constraints Data Figure Designand View forRelations searching for and displaying an order Chapter 9 - ADO.NET Exception Handling

Figure Thewith Addthe Web Reference locator Chapter 10 - 15-6: Working ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

Figure 15-7: Web services available on the local server


Chapter 13 - 15-8: Developing a Web Custom Data Provider Figure Adding references Chapter 14 - Developing Database Web Applications using ASP.NET

Figure generated theServices Web References Wizard to access the Web service Chapter 15 - 15-9: UsingFiles ADO.NET in Xml by Web Chapter 16 - ASP.NET Server Controls and Data Binding

Figure 15-10: Result of the Fill method in a DataGrid


Chapter 18 - 15-11: Object-Relational Mapping inand .NET Figure The InsertOrder GetOrderFromDatabase methods of Chapter 19 - Mapped Objects: Performance Considerations and Data Binding OrderRetrievalWebService Chapter 20 - COM Interoperability and ADO.NET

Figure Design View of the order customer entry Web service Chapter 21 - 15-12: Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Figure 15-13: Adding an order to the database using Enter Order


Chapter 16: ASP.NET Server Controls and Data Binding


List ofFigure Figures16-1: Adding Button controls to a Web page List of Tables

Figure 16-2: Loading an image in an ImageButton control

List of Listings

List ofFigure Sidebars 16-3: The Calendar control in action

Figure 16-4: Using a ListBox Web server control Figure 16-5: Data binding in a ListBox control Figure 16-6: Data binding in a DropDownList control Figure 16-7: Data binding in a DataList control Figure 16-8: Multiple columns in a DataList control Figure 16-9: Editable DataList control

Figure 16-10: A DataList control in editable mode


ISBN:1590590732 Mahesh Chandwindow and David Figure 16-11:byThe Properties of aTalbot DataList control


Figure 16-12:This Data binding in aextensive DataGrid controlof ADO.NET technology text provides coverage including ADO.NET internals, namespaces, classes, and

Figure 16-13:interfaces, The DataGrid and takes control a comprehensive with the newlook styles at XML namespaces and classes, and how to integrate both with

Figure 16-14:ADO.NET. DataGrid with BoundColumns Figure 16-15: A DataGrid control with button columns

Table of Contents

Applied ADO.NET—Building Data-Driven Solutions Figure 16-16: Using template columns Introduction

Figure DataGrid Chapter 1 - 16-17: ADO.NET Basics with EditCommandColumn Chapter 2


Chapter 3


Chapter 4


Figure 16-18:DataGrid with Save and Cancel options

Chapter 17: Building Real-World Web Applications - Handling ADO.NET Events

Chapter 5 Chapter 6


Figure The Online Job Board application architecture Chapter 7 - 17-1: Data Binding and Windows Forms Data-Bound Controls Chapter 8


Chapter 9


Figure 17-2: Schema of the Job table

Chapter 10 - 17-3: Working with the .NET Data Provider Figure Schema of ODBC the Resumes table Chapter 11 - Stored Procedures and Views

Figure Schema of and the Users tableData Providers Chapter 12 - 17-4: Oracle, SQLXML, Other .NET Chapter 13 - Developing a Custom Data Provider

Figure 17-5: The Login.aspx page

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - 17-6: UsingSetting ADO.NET Xml Web Services Figure theinNavigateUrl property of a HyperLink control Chapter 16 - ASP.NET Server Controls and Data Binding

Figure TheReal-World Register.aspx page Chapter 17 - 17-7: Building Web Applications Chapter 18 - Object-Relational Mapping in .NET

Figure 17-8: The Contact.aspx page

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - 17-9: COM Interoperability and ADO.NET Figure The PostJob.aspx page Chapter 21 - Messaging

Figure The PostResume.aspx page Chapter 22 - 17-10: SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Figure 17-11: The DisplayData.aspx page


Appendix C - 17-12: ADO.NET Asked Questions Figure TheFrequently Resumes.aspx page Index List ofFigure Figures17-13: The dnjHeader.aspx page List of Tables

17-14: The job board List ofFigure Listings List of Sidebars

Figure 17-15: View Jobs page Figure 17-16: The View Resumes page

Chapter 18: Object-Relational Mapping in .NET Figure 18-1: Basic concept of OR mapping Figure 18-2: The VideoTape test case output Figure 18-3: The output of the UserTestCase program

Figure 18-4: The dependencies in the video store application


ISBN:1590590732 David Talbot Figure 18-5: by TheMahesh outputChand of the and CheckInCheckOut test case

Apress © 2003 (928 pages) text provides extensive coverage of ADO.NET technology Chapter 19:This Mapped Objects: Performance Considerations and Data including ADO.NET internals, namespaces, classes, and Binding interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Figure 19-1: The output of the TestDataGrid program 19-2: The output of the TestGridObjects page Table Figure of Contents Applied ADO.NET—Building Data-Driven Solutions

Figure 19-3: The output of the FancyBinding page with the description shortened

Introduction

Chapter 1 - 19-4: ADO.NET Figure The Basics output of the FancyBinding page with the description expanded Chapter 2 - Data Components in Visual Studio .NET

Figure The in data in the VideoCategory table Chapter 3 - 19-5: ADO.NET Disconnected Environments Chapter 4


Chapter 5


Figure 19-6: The output of the test harness

Chapter 6 - 19-7: Integrating XML with ADO.NET Figure The BlockedTree table with data Chapter 7 - Data Binding and Windows Forms Data-Bound Controls

Figure The output of the LazyLoading page Chapter 8 - 19-8: Constraints and Data Relations Chapter 9

ADO.NET Exception Handling Figure- 19-9: The incremental lazy loading test case output


Chapter 20: COM Interoperability and ADO.NET


Figure 20-1: Adding a reference to a COM library

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - 20-2: UsingNamespace ADO.NET in Xml Services Figure afterWeb adding ADODB namespace to the project Chapter 16 - ASP.NET Server Controls and Data Binding

Figure Displaying data from an ADO recordset to a DataGrid Chapter 17 - 20-3: Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET

Figure 20-4: Adding a reference to ADOX library

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - 20-5: COM Interoperability and ADO.NET Figure ADOX namespace listed in project references Chapter 21 - Messaging

Figure Browsing msadomd.dll Chapter 22 - 20-6: SQL Server and the ADO.NET: Notes on library Performance Appendix A - Relational Databases: Some Basic Concepts

Figure 20-7: Adding a reference to msadomd.dll library


Appendix C - 20-8: ADO.NET Frequently Asked Questions Figure ADOMD namespace listed in the project namespaces Index List ofFigure Figures20-9: Windows form to test ADOMD List of Tables

Figure 20-10: All available cubes in the FoodMart 2000 database

List of Listings

List ofFigure Sidebars 20-11: Getting dimensions of a cube

Figure 20-12: Viewing dimension properties

Chapter 21: Messaging Figure 21-1: Viewing the Messaging Queuing node from Computer Management Figure 21-2: Managing message queues through the Server Explorer Figure 21-3: Message Queue Manager form Figure 21-4: A simple messaging application

Figure 21-5: Applied Messaging ADO.NET: application Building in action Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

Figure 21-6: Apress Creating a transactional queue using the Server Explorer © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology

namespaces, classes, and on Performance Chapter 22:including SQL ADO.NET Serverinternals, and ADO.NET: Notes interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Figure 22-1: ADO.NET. The Manage Indexes menu in Enterprise Manager

Figure 22-2: The Manage Indexes dialog box Table of Contents

Figure 22-3: The Create New Index dialog box


Introduction Figure 22-4: The Trace Properties dialog box Chapter 1 - ADO.NET Basics

Figure The SQL Server Profiler with a trace running Chapter 2 - 22-5: Data Components in Visual Studio .NET Chapter 3


Chapter 4


Figure 22-6: The Query Analyzer's recommendations for the current query

Chapter 5 - 22-7: Handling Events Figure TheADO.NET Query Analyzer's recommendation to create an index that would help the query run Chapter 6 Integrating XML with ADO.NET faster Chapter 7


Figure The estimated Chapter 8 - 22-8: Constraints and Data execution Relations plan of the query in Listing 22-1 Chapter 9


Figure 22-9: The estimated execution plan of the query in Listing 22-2


Chapter 11 - 22-10: Stored A Procedures Figure join table and that Views doesn't need a primary key Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Figure Generic data access class consumer application Chapter 13 - 22-11: Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Appendix A: Relational Databases: Some Basic Concepts


Chapter 16 - ASP.NET Server Controls and Data Binding Chapter Figure 17 - A-1: Building Customers Real-World table Web before Applications normalization Chapter 18 - Object-Relational Mapping in .NET

Figure A-2: Two rows of data from the Customers table

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - A-3: COMCustomers Interoperability ADO.NET Figure tableand schema after 1NF Chapter 21 - Messaging

Figure ofand the ADO.NET: Customers tableonafter 1NF Chapter 22 - A-4: SQL Data Server Notes Performance Appendix A - Relational Databases: Some Basic Concepts


Appendix B - Commonly Used SQL Statements Appendix C - A-6: ADO.NET Frequently Asked Figure Orders table after 2NFQuestions Index List ofFigure FiguresA-7: Relationship between the Customers and Orders tables List of Tables


List of Listings

List ofFigure Sidebars A-9: Orders table after 2NF

Figure A-10: Orders table after 3NF Figure A-11: Data of the Orders table after 3NF

Appendix B: Commonly Used SQL Statements Figure B-1: Creating a new query in Access 2000 Figure B-2: Selecting database tables Figure B-3: The Query Editor of Access 2000

Figure B-4: Customers table schema of the Northwind database Applied ADO.NET: Building Data-Driven Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

Figure B-5: Orders table schema of the Northwind database Apress © 2003 (928 pages)

This text extensive coverage of ADO.NET technology Figure B-6: Output of provides the SELECT statement including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML

Figure B-7: Output of SELECT * FROM Customers statement namespaces and classes, and how to integrate both with ADO.NET.

Figure B-8: Output of the SELECT...WHERE statement B-9: Output of query that uses the SQL SUM function Table Figure of Contents Applied ADO.NET—Building Data-Driven Solutions

Figure B-10: Output of COUNT

Introduction

Chapter 1 - B-11: ADO.NET Basics Figure Output of GROUP BY Chapter 2 - Data Components in Visual Studio .NET

Figure Output of the AliasEnvironments statement Chapter 3 - B-12: ADO.NET in Disconnected Chapter 4


Figure- B-13: Output of the JOIN statement Handling ADO.NET Events

Chapter 5 Chapter 6


Appendix ADO.NET Frequently Asked - DataC: Binding and Windows Forms Data-Bound ControlsQuestions

Chapter 7 Chapter 8


Figure Paging in an ADO.NET Chapter 9 - C-1: ADO.NET Exception Handling application Chapter 10 - Working with the ODBC .NET Data Provider

Figure C-2: Getting a database schema programmatically


Chapter 12 - C-3: Oracle, SQLXML, Other .NET Data Providers Figure Users table and schema Chapter 13 - Developing a Custom Data Provider

Figure Reading and writing in a database final form Chapter 14 - C-4: Developing Database Web images Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services

Figure C-5: Displaying a bitmap after reading data from a database

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - C-6: Building Real-World Web Applications Figure DiffGram format Chapter 18 - Object-Relational Mapping in .NET


Applied ADO.NET: Building Data-Driven Solutions List of Tables ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

Chapter 3: This ADO.NET inextensive Disconnected Environments text provides coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Table 3-1: The System.Data Namespace Classes


Table 3-2: The System.Data.Common Namespace Classes 3-3: The DataColumn Class Properties Table Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Table 3-4: The DataRow Class Properties

Introduction

Chapter 1 -3-5: ADO.NET Basics Table The DataRow Class Methods Chapter 2 - Data Components in Visual Studio .NET

Table The DataRowState Enumeration Members Chapter 3 -3-6: ADO.NET in Disconnected Environments Chapter 4


Chapter 5


Table 3-7: The DataTable Class Properties

Chapter 6 -3-8: Integrating XML with ADO.NET Table The DataTable Class Methods Chapter 7


Table The DataView Properties Chapter 8 -3-9: Constraints and DataClass Relations Chapter 9


Table 3-10: The DataView Class Methods


Table 3-11:DataSetView Properties


Chapter 4: ADO.NET in Connected Environments


Table 4-1: Sql Data Provider Classes

Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 -4-2: Building Real-World Web Applications Table Connection Object Properties Chapter 18 - Object-Relational Mapping in .NET Chapter Table 19 -4-3: Mapped The ConnectionType Objects: Performance Enumeration Considerations Members and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Table The Connection Class Members Chapter 21 -4-4: Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Table 4-5: The OLE DB Services Settings

Appendix A - Relational Databases: Some Basic Concepts Appendix B -4-6: Commonly Used Pooling SQL Statements Table Connection Settings Appendix C - ADO.NET Frequently Asked Questions IndexTable 4-7: The Command Properties List of Figures

Table 4-8: The CommandType Enumeration Members

List of Tables

List ofTable Listings 4-9: The DataReader Properties List of Sidebars

Table 4-10: The DataReader Methods Table 4-11: The SqlDataAdpater Class Properties Table 4-12:OleDbDataAdapter Command Properties with Examples Table 4-13: The DataAdapter Methods Table 4-14: The SqlParameter Class Properties Table 4-15: Methods of the Transaction Class Table 4-16: Isolation Levels Available for Transactions

Table 4-17:Transaction Applied ADO.NET: Methods Building in theData-Driven Sql Data Provider Solutions by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

Chapter 5: Handling ADO.NET Events

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Table 5-1: InfoMessageEventArgs Properties look at XML interfaces, and takes a comprehensive namespaces and classes, and how to integrate both with Table 5-2: The ConnectionState Enumeration Members ADO.NET.

Table 5-3: The FillErrorEventArgs Members Table of Contents

Table 5-4: The SqlRowUpdatedEventArgs Members Applied ADO.NET—Building Data-Driven Solutions Introduction

Table 5-5: The DataTable Events

Chapter 1

- ADO.NET Basics

Chapter 2 -5-6: Data Components in Visual Studio .NET Table XmlDataDocument Events Chapter 3


Chapter Table 4 -5-7: ADO.NET The XmlNodeChangedEventArgs in Connected Environments Properties Chapter 5

- Handling ADO.NET Events Table The ListChangedEventArgs Members Chapter 6 -5-8: Integrating XML with ADO.NET Chapter 7


Chapter - Constraints 6: Integrating and Data Relations XML with ADO.NET

Chapter 8 Chapter 9


Chapter Table 10 -6-1: Working The XmlNodeType with the ODBC .NET Enumeration's Data Provider Members Chapter 11 - Stored Procedures and Views

Table The SQLXML, XmlReader Class.NET Properties Chapter 12 -6-2: Oracle, and Other Data Providers Chapter 13 - Developing a Custom Data Provider

Table 6-3: The XmlReader Class Methods

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 -6-4: Using ADO.NET in Xml Web Services Table Some XmlElement Class Methods Chapter 16 - ASP.NET Server Controls and Data Binding

Table The XmlReadMode Chapter 17 -6-5: Building Real-World Web Members Applications Chapter 18 - Object-Relational Mapping in .NET

Table 6-6: The XmlWriteMode Members

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 -6-7: COM Interoperability and ADO.NET Table XPathNavigator Members Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Chapter 7: Data Binding and Windows Forms Data-Bound Controls


Table 7-1: The BindingManagerBase Class Methods


IndexTable 7-2: The DataGrid Class Properties List of Figures List ofTable Tables7-3: The DataGrid Class Methods List of Listings

Table 7-4: The DataGrid Class Protected Methods

List of Sidebars

Table 7-5: The DataGridColumnStyle Properties Table 7-6: The DataGridColumnStyle Methods Table 7-7: The DataGridBoolColumn Properties Table 7-8: The DaaGrid.HitTestType Enumeration

Chapter 8: Constraints and Data Relations Table 8-1: The ForeignKeyConstraint Class Properties

Table 8-2: The UniqueConstraint Class Properties Solutions Applied ADO.NET: Building Data-Driven by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

Table 8-3: The ConstraintCollection Class Methods

This text provides extensive coverage of ADO.NET technology Table 8-4: The DataRelation Class Properties including ADO.NET internals, namespaces, classes, and

interfaces, and takes a comprehensive look at XML Table 8-5: The DataRelationCollection Class Methods


Chapter 9: ADO.NET Exception Handling Table of Contents

Table 9-1: Exception Class Properties

Applied ADO.NET—Building Data-Driven Solutions Introduction Table 9-2: The System.Data Exception Classes Chapter 1 - ADO.NET Basics Chapter Table 2 -9-3: Data Severity Components Levelsin Visual Studio .NET Chapter 3


Table -9-4: The SqlException Class Properties ADO.NET in Connected Environments

Chapter 4 Chapter 5


Chapter 10: Working with the ODBC .NET Data Provider - Integrating XML with ADO.NET

Chapter 6 Chapter 7


Table The ODBC .NETRelations Data Provider Classes Chapter 8 -10-1: Constraints and Data Chapter 9


Chapter 11: Stored Procedures and Views


Chapter 12 -11-1: Oracle, and Other .NET Data Providers Table TheSQLXML, ParameterDirection Members Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Chapter 12: Oracle, SQLXML, and Other .NET Data Providers



Table 12-1: Oracle Data Provider Classes

Chapter 17 - Building Real-World Web Applications Chapter 18 -12-2: Object-Relational Mapping in Properties .NET Table The SqlXmlCommand Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Table SqlXmlCommandType Chapter 20 -12-3: COM The Interoperability and ADO.NET Members Chapter 21 - Messaging

Chapter 13: Developing a Custom Data Provider


Appendix B -13-1: Commonly Used SQL of Statements Table The Properties the IDbConnection Interface Appendix C - ADO.NET Frequently Asked Questions IndexTable 13-2: The Methods of the IDbConnection Interface List of Figures

Table 13-3: The Properties of the IDbCommand Interface

List of Tables

List ofTable Listings 13-4: The Methods of the IDbCommand Interface List of Sidebars

Table 13-5: The Properties of the IDataReader Interface Table 13-6: The Methods of the IDataReader Interface Table 13-7: The Properties of the IDataRecord Interface Table 13-8: The Methods of the IDataRecord Interface Table 13-9: The Properties of the IDbDataAdapter Interface Table 13-10: The Properties of the IDbDataAdapter Object

Table 13-11: The Methods of the IDbDataAdapter Object


ISBN:1590590732

Chapter 14:Apress Developing Database Web Applications using ASP.NET © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology

Table 14-1: HTML Server Controls including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Table 14-2: Web Server Controls ADO.NET.

Table 14-3: Validation Controls Table Table of Contents 14-4: ASP.NET Data-Bound Controls Applied ADO.NET—Building Data-Driven Solutions

Table 14-5:DataGrid Control Properties Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Table 14-6: Web Controls on MyGuestBook.aspx Page

Chapter 3 -14-7: ADO.NET Disconnected Environments Table WebinControls of ViewGuestBook.aspx Chapter 4

- ADO.NET in Connected Environments Table Controls of Thanks.aspx Page Chapter 5 -14-8: Handling ADO.NET Events Chapter 6


- Data and Windows Forms Data-Bound Controls Chapter 16:Binding ASP.NET Server Controls and Data Binding

Chapter 7 Chapter 8


Chapter 9 -16-1: ADO.NET Exception Handling Table The Calendar Class Properties Chapter 10 - Working with the ODBC .NET Data Provider

Table ASP.NET Templates Chapter 11 -16-2: Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Table 16-3: Templates Supported by the Repeater Control


Chapter 14 -16-4: Developing Database Web Applications usingFormat ASP.NET Table The Values of the B Part of the Data String of ListControl Chapter 15 - Using ADO.NET in Xml Web Services

Table The Server BaseDataList Class Chapter 16 -16-5: ASP.NET Controls and DataProperties Binding Chapter 17 - Building Real-World Web Applications

Table 16-6: The DataList Class Properties



Table 16-7: The TableItemStyle Class Properties


Chapter 21 -16-8: Messaging Table The DataGrid Control Events Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Chapter 18: Object-Relational Mapping in .NET



Table 18-1: The VideoTape Table

Index

List ofTable Figures 18-2: The VideoCheckIn Table List of Tables

Table 18-3: The VideoCheckOut Table

List of Listings

List ofTable Sidebars 18-4: The Users Table

Chapter 19: Mapped Objects: Performance Considerations and Data Binding Table 19-1: The VideoCategory Table, the Poor Performance Way Table 19-2: The VideoCategory Table, the High Performance Way Table 19-3: The BlockedTree Table Table 19-4: An Indexed Table

Building Data-Driven Solutions Chapter 20:Applied COMADO.NET: Interoperability and ADO.NET by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

ISBN:1590590732

Table 20-1:Tlbimp.exe Options

This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and Table 20-2:Tlbexp.exe Options interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Chapter 21: Messaging

21-1: The MessageQueue Class Properties Table Table of Contents Applied ADO.NET—Building Data-Driven Solutions

Table 21-2: The MessageQueueCriteria Class Properties

Introduction

Chapter 1 -21-3: ADO.NET Table Path Basics for Different Types of Queues Chapter 2 - Data Components in Visual Studio .NET

Table The MessagePriority Enumeration Members Chapter 3 -21-4: ADO.NET in Disconnected Environments Chapter 4


- Handling ADO.NET EventsDatabases: Some Basic Concepts Appendix A: Relational

Chapter 5 Chapter 6


Chapter 7 -A-1: DataRecordset Binding and Windows Data-Bound Table Cursor TypeForms and Their ValuesControls in ADO Chapter 8


Table Isolation Levels Handling Chapter 9 -A-2: ADO.NET Exception Chapter 10 - Working with the ODBC .NET Data Provider

Table A-3: Isolation Levels and Data Consistency


Chapter 12 -A-4: Oracle, SQLXML, and Other .NET Data Providers Table Locking Types Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Appendix B: Commonly Used SQL Statements



Table B-1: Conditional Statements Used in SQL


Appendix C: ADO.NET Frequently Asked Questions


Table C-1:IDataReader Meta-Data


Chapter 22 -C-2: SQLThe Server and ADO.NET: on Performance Table Registry ClassNotes Members Appendix A - Relational Databases: Some Basic Concepts Appendix Table B -C-3: Commonly The RegistryKey Used SQL Statements Class Properties Appendix C - ADO.NET Frequently Asked Questions IndexTable C-4: The RegistryKey Class Methods List of Figures

Table C-5: The DiffGram Elements

List of Tables

List ofTable Listings C-6: The DataRowState Members List of Sidebars

Table C-7: The CommandBehavior Enumeration

Applied ADO.NET: Building Data-Driven Solutions List of Listings ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

Chapter 1: This ADO.NET Basics text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML Listing 1-1: Your ADO.NET Application


Listing 1-2: Viewing Data from a SQL Server Database to a DataGrid Control

Chapter 2: Data Components in Visual Studio .NET

Table of Contents

Applied ADO.NET—Building Data-Driven Solutions Introduction Listing 2-1: Added Sql Server Provider Components Chapter 1 - ADO.NET Basics

Listing DataAdapter through Chapter 2 - 2-2: Data Components inConnection Visual Studio .NET TableMapping Chapter 3


Chapter 4


Listing 2-3: Form's Load Event Handler

Chapter 5 - 2-4: Handling ADO.NET Events from a Button Click Listing Calling DataForm1 Chapter 6 - Integrating XML with ADO.NET

Listing a Button Click Controls Chapter 7 - 2-5: DataCalling BindingDataForm2 and Windowsfrom Forms Data-Bound Chapter 8


Listing- 2-6: The Load and Update Button Click Event Handlers ADO.NET Exception Handling

Chapter 9

Chapter 10 - 2-7: Working with the ODBC .NETGenerated Data Provider Listing LoadDataSet Method by the Data Form Wizard Chapter 11 - Stored Procedures and Views Chapter Listing 12 - 2-8: Oracle, TheSQLXML, FillDataSet and Other Method .NET Data Generated Providers by the Data Form Wizard Chapter 13 - Developing a Custom Data Provider

Listing The UpdateDataSource and UpdateDataSet Methods Generated by the Data Form Chapter 14 - 2-9: Developing Database Web Applications using ASP.NET Wizard Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Listing 2-10: Cancel All Button Click Event Handler


Chapter 3: ADO.NET in Disconnected Environments


Listing 3-1: Creating Columns Using Different DataColumn Constructors


Chapter 22 - 3-2: SQL Creating Server and ADO.NET: Notes onSetting Performance Listing a DataColumn and Its Properties Appendix A - Relational Databases: Some Basic Concepts Appendix Listing B - 3-3: Commonly SettingUsed a DataColumn SQL Statements as the Primary Key Appendix C - ADO.NET Frequently Asked Questions IndexListing 3-4: Creating the Id and Name Data Columns of the Customers Table List of Figures

Listing 3-5: Creating a Table Using DataTable and DataColumn

List of Tables

List ofListing Listings 3-6: Using the ColumnMapping Property of DataColumn List of Sidebars

Listing 3-7: Adding and Removing Custom Properties Listing 3-8: Using the Ordinal and MaxLength Properties Listing 3-9: Setting the Values of the Id, Address, and Name Columns of a DataRow Listing 3-10: Adding Rows to a DataTable Using DataRow Listing 3-11: Calling DataRow'sRejectChanges and Delete Methods Listing 3-12: Calling the RowState Property Listing 3-13: Creating a Customer/Order Relationship Using DataRelation

Listing 3-14: Applied Form's Constructor Calling CreateCustomersTable, CreateOrdersTable, and ADO.NET: Building Data-Driven Solutions BindData by Mahesh Chand and David Talbot ISBN:1590590732 Apress © 2003 (928 pages)

Listing 3-15: This Customer/Orders Relationship Example text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

Listing 3-16: interfaces, Class-Level DataTable and DataSet and takes a comprehensive lookVariables at XML


Listing 3-17: ADO.NET. The CreateCustomersTable Method Listing 3-18: The AddRowBtn_Click Method Table of Contents

Listing 3-19: The DeleteRow_Click Method Applied ADO.NET—Building Data-Driven Solutions Introduction

Listing 3-20: The SearchButtonClick Method

Chapter 1

- ADO.NET Basics

Chapter 2 - 3-21: Data Components Visualthe Studio .NET Method Listing Sorting DatainUsing Select Chapter 3


Chapter Listing 4 - 3-22: ADO.NET Saving in Connected a DataTable Environments Data in an XML Document Chapter 5

- Handling ADO.NET Events Listing Using XML the Contains, Find, and Remove Method of DataRowCollection Chapter 6 - 3-23: Integrating with ADO.NET Chapter 7


Chapter 8


Listing 3-24: Using the InsertAt and RemoveAt Methods

Chapter 9 - 3-25: ADO.NET Exception Handlingfrom a Collection Listing Removing a Column Chapter 10 - Working with the ODBC .NET Data Provider

Listing the State Chapter 11 - 3-26: StoredDetermining Procedures and Views of a Row Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Listing 3-27: Editing Rows Using BeginEdit,CancelEdit, and EndEdit Methods


Chapter 14 - 3-28: Developing Web Applications using ASP.NET Listing SettingDatabase and Reading Custom Properties of a DataSet Chapter 15 - Using ADO.NET in Xml Web Services

Listing Adding DataTable Objects to a DataSet Chapter 16 - 3-29: ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

Listing 3-30: Using Copy,Clone, and Clear Methods of DataSet


Chapter 19 - 3-31: Mapped Objects: Performance Considerations and Data Binding Listing Merging Two DataSetse Chapter 20 - COM Interoperability and ADO.NET

Listing Merging DataRow and DataTable Objects Chapter 21 - 3-32: Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Listing 3-33: Creating DataView Objects from a DataTable


Listing 3-34: Adding, Updating, and Deleting Rows of a DataView


IndexListing 3-35: Finding Rows in a DataView Using the Find Method List of Figures List of Tables

Chapter 4: ADO.NET in Connected Environments

List of Listings

List of Sidebars

Listing 4-1: Creating SqlConnection Objects Listing 4-2: Connecting to an OleDb Database and Reading the OleDbConnection Properties Listing 4-3: Connecting to a SQL Server Using the OleDb Data Provider Listing 4-4: Connecting to a SQL Server and Reading the SqlConnection Properties Listing 4-5: Creating Two Connections with Different Strings Listing 4-6: Calling ReleaseObjectPool Listing 4-7: Setting and Getting SqlCommand Properties

Listing 4-8: Using SqlCommand to Read Data from a Database


ISBN:1590590732 by Mahesh Chand and Talbot Listing 4-9: Using OleCommand to David Access an Access Database


Listing 4-10: This Calling Stored Procedure Using SqlCommand textaprovides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and a comprehensive look in at the XMLNorthwind Database Listing 4-11: interfaces, The Salesand Bytakes Year Stored Procedure namespaces and classes, and how to integrate both with Listing 4-12: ADO.NET. Executing and Reading the Results of a Stored Procedure

Listing 4-13: Adding the Subtotal Listing to the Output of the Stored Procedure Results

Table of Contents

Applied ADO.NET—Building Data-Driven Solutions Listing 4-14: Using TableDirect to Read a Table Introduction

Listing Adding Records to a Table Using the INSERT SQL Statement Chapter 1 - 4-15: ADO.NET Basics Chapter 2


Chapter 3


Listing 4-16: Using the ExecuteScalar Method to Retrieve a Single Value

Chapter 4 - 4-17: ADO.NET in Connected Environments Listing DataReader Reads Data from a SQL Server Database Chapter 5 - Handling ADO.NET Events

Listing Executing Using DataReader Chapter 6 - 4-18: Integrating XML Batches with ADO.NET Chapter 7


Chapter 8


Listing 4-19: Creating SqlDataAdapter Instances

Chapter 9 - 4-20: ADO.NET Exception Handling* Statement Using OleDbDataAdapter Listing Executing a SELECT Chapter 10 - Working with the ODBC .NET Data Provider Chapter Listing 11 - 4-21: StoredUsing Procedures SqlDataAdapter and Views Properties Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Listing Calling DataAdapter's Chapter 13 - 4-22: Developing aa Custom Data ProviderFill Method Chapter 14 - Developing Database Web Applications using ASP.NET

Listing 4-23: Using the FillSchema Method of SqlDataAdapter


Chapter 16 - 4-24: ASP.NET Server Controls andTable Data Binding Listing Displaying the Orders Data in a DataGrid Using OleDbDataAdapter Chapter 17 - Building Real-World Web Applications

Listing Displaying the Customers Chapter 18 - 4-25: Object-Relational Mapping in .NETTable's Data in a DataGrid Using SqlDataAdapter Chapter 19 - Mapped Objects: Performance Considerations and Data Binding

Listing 4-26: Setting the DeleteCommand Property of DataAdapter


Chapter 21 - 4-27: Messaging Listing Creating a SqlParameter Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Listing Calling the FillSome Method ofConcepts a DataAdapter Appendix A - 4-28: Relational Databases: Basic Appendix B - Commonly Used SQL Statements

Listing 4-29: Removing a Row and Calling the Update Method of a DataAdapter


Listing 4-30: Calling a DataAdapter'sUpdate Method

List of Figures

List ofListing Tables4-31: Using DataTableMapping to Map the Orders Table of Northwind List of Listings

4-32: Using DataTableMapping with the Table Option List ofListing Sidebars Listing 4-33: Using DataColumnMapping Listing 4-34: Creating and Using the SqlCommandBuilder Class Listing 4-35: Creating a Parameter Listing 4-36: Filling Data from Multiple Tables Listing 4-37: Merging Two DataSet Objects Listing 4-38: Adding, Editing, and Deleting a DataSet Rows

Listing 4-39: Using the AcceptChanges and RejectChanges Methods of a DataSet Applied ADO.NET: Building Data-Driven Solutions

Mahesh Chand and David Listing 4-40: by Saving Only Modified Rows Talbot of a DataSet

ISBN:1590590732


Listing 4-41: This Private textMembers provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

Listing 4-42: interfaces, The Load Data Button's Click Event Handler and takes a comprehensive look at XML namespaces and classes, and how to integrate both with

Listing 4-43: ADO.NET. Optimistic Concurrency Listing 4-44: Pessimistic Concurrency Table of Contents

Listing 4-45: Using Savepoints in Solutions the Sql Data Provider Applied ADO.NET—Building Data-Driven Introduction

Listing 4-46: Executing Multiple SQL Queries Using SqlTransaction

Chapter 1

- ADO.NET Basics

Chapter 2


Chapter 5: Handling ADO.NET Events - ADO.NET in Disconnected Environments

Chapter 3 Chapter 4

- ADO.NET in Connected Environments Listing Writing Event Handlers for the InfoMessage and StateChange Events Chapter 5 - 5-1: Handling ADO.NET Events Chapter 6


Chapter 7


Listing 5-2: Writing Code That Executes Connection Events

Chapter 8 - 5-3: Constraints and Data Relations Listing SqlDataAdapter Event Handler Bodies Chapter 9 - ADO.NET Exception Handling

Listing DataAdapter FillError Handler Code Chapter 10 - 5-4: Working with the ODBC .NET Data Event Provider Chapter 11 - Stored Procedures and Views

Listing 5-5: The RowUpdated Event Handler


Listing 5-6: The RowUpdating Event Handler

Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - 5-7: Using ADO.NET in Xml Web Services Listing Calling the DataAdapter's Fill and Update Methods Chapter 16 - ASP.NET Server Controls and Data Binding

Listing Writing Code toWeb CallApplications MergeFailed Event Handler Chapter 17 - 5-8: Building Real-World Chapter 18 - Object-Relational Mapping in .NET

Listing 5-9: Writing the ColumnChanging and ColumnChanged Event Handlers


Chapter 20 - 5-10: COM Interoperability and ADO.NETand RowChanged Event Handlers Listing Writing the RowChanging Chapter 21 - Messaging

Listing Writingand theADO.NET: RowDeleting and RowDeleted Event Handlers Chapter 22 - 5-11: SQL Server Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Listing 5-12: The XmlDataDocument Event Handling Example


Appendix C - 5-13: ADO.NET AskedEvent Questions Listing The Frequently NodeChanged Handler Index List ofListing Figures5-14: The NodeInserted Event Handler List of Tables

5-15: The NodeRemoved Event Handler List ofListing Listings List of Sidebars

Listing 5-16:DataView OnListChanged Event Handler Listing 5-17: The DataView Event Handler Caller

Chapter 6: Integrating XML with ADO.NET Listing 6-1: Reading an XML File Listing 6-2: Getting XML Node Information Listing 6-3: Getting Node Information

Listing 6-4: Using the MoveToContent Method


by Mahesh Chand and DavidofTalbot Listing 6-5: Using the GetAttribute a Node

ISBN:1590590732


Listing 6-6: Using the Skip Method This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

Listing 6-7:XmlWriter interfaces, and Example takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET. Listing 6-8: Output of the XmlWriterSample.vb Class

Listing 6-9: Using the XmlConvert Class

Table of Contents

Applied ADO.NET—Building Data-Driven Solutions Sample Listing 6-10: The XmlDocumentFragment Introduction

Listing Appending Chapter 1 - 6-11: ADO.NET Basics in an XML Document Fragment Chapter 2


Chapter 3


Listing 6-12: Adding Nodes to a Document

Chapter 4 - 6-13: ADO.NET in Connected Environments Listing Getting the Root Node of a Document Chapter 5

- Handling ADO.NET Events Listing Removing All Items of a Node Chapter 6 - 6-14: Integrating XML with ADO.NET Chapter 7


Chapter 8


Listing 6-15: Calling RemoveAll for books.xml

Chapter 9 - 6-16: ADO.NET Exception Handling Listing Calling ReplaceChild Chapter 10 - Working with the ODBC .NET Data Provider

Listing an XML Fragment into a Document Chapter 11 - 6-17: StoredInserting Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Listing 6-18: Adding a Node with Attributes


Chapter 14 - 6-19: Developing Database Web Applications using ASP.NET Listing An XSL Transformation Chapter 15 - Using ADO.NET in Xml Web Services

Listing Using the WriteXml Chapter 16 - 6-20: ASP.NET Server Controls andMethod Data Binding Chapter 17 - Building Real-World Web Applications

Listing 6-21:WriteXml Method Output

Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - 6-22: Mapped Objects: Performance Considerations Listing Using the WriteXmlSchema Method and Data Binding Chapter 20 - COM Interoperability and ADO.NET

Listing XmlDataDocumentSample.vb Chapter 21 - 6-23: Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Listing 6-24: Saving the DataSet Data to an XML Document


Appendix B - 6-25: Commonly Used SQL Statements Listing Moving to Root and First Child Nodes Using XPathNavigator Appendix C - ADO.NET Frequently Asked Questions IndexListing 6-26: Reading a Document Using XPathNavigator List of Figures

Listing 6-27: Using XPathIterator and Select

List of Tables

List of Listings

Listing 6-28: The XML Schema Generated for a Database Table

List of Sidebars

Chapter 7: Data Binding and Windows Forms Data-Bound Controls Listing 7-1: Binding a TextBox Using Binding Listing 7-2: Binding Multiple Controls Using Binding Listing 7-3: Counting and Removing Binding Objects Listing 7-4: Reading All the Bindings of a Form Listing 7-5: Reading a TextBox Control's Binding Properties

Listing 7-6: Adding Format and Parse Event Handlers


ISBN:1590590732 by Mahesh and David Talbotin Data Binding Listing 7-7: Reading All Chand Controls Participating


Listing 7-8: Record Navigation System Variables This text provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

Listing 7-9:LoadData Methodslook at XML interfaces,and andGetDataSet takes a comprehensive


Listing 7-10: ADO.NET. Move Next, Move Previous, Move First, and Move Last Button Code Listing 7-11: Adding a ListBox Control Event Handler Table of Contents

Listing 7-12: Raising Data-Driven ListBox Events Applied ADO.NET—Building Solutions Introduction

Listing 7-13: The Form Load Event Handler

Chapter 1

- ADO.NET Basics

Chapter 2 - 7-14: Data Components in Visual Method Studio .NET Listing The FillDataSet Chapter 3

- ADO.NET in Disconnected Environments Listing Binding ListBoxEnvironments and ComboBox Controls Chapter 4 - 7-15: ADO.NET in Connected Chapter 5


Listing- 7-16: Setting the DataSource and DataMember Properties of a DataGrid Control Integrating XML with ADO.NET

Chapter 6 Chapter 7

Data Binding and Windows Forms Data-Bound Controls Listing- 7-17: Creating and Adding a DataGridTableStyle

Chapter 8


Chapter 9 - 7-18: ADO.NET Exception Handling Listing Creating a DataGridTableStyle from CurrencyManager Chapter 10 - Working with the ODBC .NET Data Provider

Listing a DataGridBoolColumn Chapter 11 - 7-19: StoredCreating Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Listing 7-20:AllowNavigation in Action


Chapter 14 - 7-21: Developing Applications Color using ASP.NET Listing Using Database Some of Web the DataGrid's and Font Properties Chapter 15 - Using ADO.NET in Xml Web Services

Listing TheServer DataGrid's Properties Chapter 16 - 7-22: ASP.NET ControlsCaption and Data Binding Chapter 17 - Building Real-World Web Applications

Listing 7-23: Form's Load Method

Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - 7-24: Mapped Objects: PerformanceMethod Considerations and Data Binding Listing The CreateDataSet Chapter 20 - COM Interoperability and ADO.NET Chapter Listing 21 - 7-25: Messaging The FillDataGrid Method Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Listing Seeing HitTest in Action Appendix A - 7-26: Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements

Listing 7-27: The FillDataGrid and Form_Load Methods


IndexListing 7-28: Exchanging the Button Click Handler List of Figures List ofListing Tables7-29: The ReshuffleColumns Method List of Listings

Listing 7-30: Getting a DataGrid Columns' Style Using DataGridColumnStyle

List of Sidebars

Listing 7-31: Getting a DataGrid Column Header Name Listing 7-32: Getting the Current DataGridColumnStyle Listing 7-33: Sorting a DataGrid Control's Columns Listing 7-34:CustRecordSet.vb Listing 7-35: Creating a Custom Recordset Listing 7-36: Moving Record Button Click Event Handlers

Listing 7-37:FillDataGrid Method


Mahesh Chand and DavidHandler Talbot Listing 7-38: by Seach Button Click Event

ISBN:1590590732


Listing 7-39: This Saving in a Data Source from a DataGrid textUpdated providesData extensive coverage of ADO.NET technology Control including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with ADO.NET.

Chapter 8: Constraints and Data Relations Listing 8-1: Creating a FOREIGN KEY Constraint Table Listing of Contents 8-2: Creating a UNIQUE Constraint Applied ADO.NET—Building Data-Driven Solutions

Listing 8-3: Adding and Removing Constraints Introduction Chapter 1

- ADO.NET Basics

Chapter 2


Listing 8-4: Adding UNIQUE Constraints

Chapter 3 - 8-5: ADO.NET in Disconnected Environments Listing Reading All the Constraints of a Collection Chapter 4

- ADO.NET in Connected Environments Listing Adding a PRIMARY Chapter 5 - 8-6: Handling ADO.NET EventsKEY Constaint to a DataTable Chapter 6


Chapter 7


Listing 8-7: Filling a DataSet from Two Tables

Chapter 8 - 8-8: Constraints Data Relations Listing Creatingand a DataRelation Chapter 9


Listing Getting Properties Chapter 10 - 8-9: Working withDataRelation the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

Listing 8-10: Deleting a Data Relation from the Collection


Chapter 9: ADO.NET Exception Handling


Listing Opening a File Chapter 16 - 9-1: ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications

Listing 9-2: A Simple Exception Handling Block


Chapter 19 - 9-3: Mapped Objects: Performance Considerations and Data Binding Listing A Simple Try...Catch Block Chapter 20 - COM Interoperability and ADO.NET

Listing The Try...Catch...Finally Statement Chapter 21 - 9-4: Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Listing 9-5: Using Nested Try...Catch and Multiple Catch Blocks


Appendix B - 9-6: Commonly Used SQL Statements Listing Defining a Custom Filter and Error Message Appendix C - ADO.NET Frequently Asked Questions IndexListing 9-7: Reading Data from a SQL Server List of Figures

Listing 9-8: Using the SqlError and SqlErrorCollection Objects

List of Tables

List of Listings

Chapter 10: Working with the ODBC .NET Data Provider

List of Sidebars

Listing 10-1: Reading Data from Northwind Using the ODBC Data Provider Listing 10-2: Accessing a MySQL Database Listing 10-3: Accessing the TextDB.txt File Listing 10-4: Accessing Employees.xls Using the ODBC Data Provider

Chapter 11: Stored Procedures and Views Listing 11-1: Executing the mySP Stored Procedure Using the Sql Data Provider

ADO.NET:in Building Listing 11-2: Applied Using Parameters a StoredData-Driven Procedure Solutions by Mahesh Chand and David Talbot

ISBN:1590590732

Listing 11-3:AddCat1 Stored Procedure Apress © 2003 (928 pages) This text provides extensive coverage of ADO.NET technology

Listing 11-4: including ExecutingADO.NET a Storedinternals, Procedure with Output Parameter namespaces, classes, and interfaces, and takes a comprehensive look at XML

Listing 11-5: namespaces Executing a and Viewclasses, Programmatically and how to integrate both with ADO.NET.

Chapter 12: Oracle, SQLXML, and Other .NET Data Providers Table of Contents

Listing 12-1: Connecting to an Oracle Database Applied ADO.NET—Building Data-Driven Solutions Introduction

Listing 12-2:FillDataGrid Method

Chapter 1

- ADO.NET Basics

Chapter 2 - 12-3: Data ExecuteSqlQuery Components in Visual Method Studio .NET Listing Chapter 3

- ADO.NET in Disconnected Environments Listing Constructing SQLEnvironments INSERT,UPDATE, and DELETE Queries Chapter 4 - 12-4: ADO.NET in Connected Chapter 5


Chapter 6


Listing 12-5: Reading Data Using OracleDataReader

Chapter 7 - 12-6: Data Binding andOracle-Specific Windows FormsDataReader Data-Bound Controls Listing Using the Methods Chapter 8


Chapter Listing 9 - 12-7: ADO.NET Reading Exception and Writing Handling Data Using OracleDataAdapter Chapter 10 - Working with the ODBC .NET Data Provider

Listing SqlXmlAdapter Chapter 11 - 12-8: StoredUsing Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Listing 12-9: Using SqlXmlCommand to Execute Commands



Chapter 13: Developing a Custom Data Provider



Listing TheReal-World Implementation for an Enumerator Chapter 17 - 13-1: Building Web Applications Chapter 18 - Object-Relational Mapping in .NET

Listing 13-2: The PipedDataConnection Object

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - 13-3: COM Interoperability and ADO.NETObject Listing The PipedDataCommand Chapter 21 - Messaging

Listing The PipedDataReader Chapter 22 - 13-4: SQL Server and ADO.NET: NotesObject on Performance Appendix A - Relational Databases: Some Basic Concepts

Listing 13-5: The PipedDataAdapter Object


Appendix C - 13-6: ADO.NET Asked Questions Listing The Frequently PipedDataProvider Test Case Index List of Figures

Chapter 14: Developing Database Web Applications using ASP.NET

List of Tables

List of Listings

Listing 14-1: Filling Data from a Database to Data-Bound Controls

List of Sidebars

Listing 14-2: ASP.NET Version of Your First ASP.NET Application Listing 14-3: Filling the DataSet from DataAdapter Listing 14-4: The PageIndexChanged Handler of the DataGrid Control Listing 14-5: HTML View of asp:DataGrid Listing 14-6: Setting the AllowPaging,PageSize, and AllowSorting Properties Listing 14-7: Setting DataGrid's PageStyle Modes

Listing 14-8: Setting the DataGrid Control's PageStyle Text


Mahesh David Talbot Listing 14-9: by Setting an Chand Image and as the DataGrid Control'sISBN:1590590732 Next and Previous Page Text Apress © 2003 (928 pages)

Listing 14-10:This Thetext FillDataGrid Method provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

Listing 14-11:interfaces, The ExecuteSQL and takes Method a comprehensive look at XML namespaces and classes, and how to integrate both with

Listing 14-12:ADO.NET. Add Button Click Event Handler Listing 14-13: Updating Data on the Update Button Click

Table of Contents

Applied Listing ADO.NET—Building 14-14: Deleting Data-Driven Data on the Solutions Delete Button Click Introduction

Listing- 14-15: Adding Guest Data to the Database ADO.NET Basics

Chapter 1

Chapter 2 - 14-16: Data Components in Visual Studio .NET Listing Opening ViewGuestBook.aspx Chapter 3


Chapter Listing 4 - 14-17: ADO.NET Page_Load in Connected Event Environments Handler Code of ViewGuestBook.aspx Chapter 5

- Handling ADO.NET Events Listing My Home Page and View Guest Book Buttons Chapter 6 - 14-18: Integrating XML with ADO.NET Chapter 7


Chapter 15: Using ADO.NET in Xml Web Services Chapter 8 - Constraints and Data Relations Chapter 9

- ADO.NET Exception Handling Listing Thewith GetOrdersFromDatabase Method for Obtaining an Order from an Order ID Chapter 10 - 15-1: Working the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views

Listing 15-2: Adding Descriptions to the WebService and WebMethod Attributes


Listing 15-3: Button-Click Event Handler That Calls the Order Retrieval Web Service


Chapter Listing 15 - 15-4: UsingWeb ADO.NET Service in Xml Method Web Services for Populating an Order in the Database Chapter 16 - ASP.NET Server Controls and Data Binding

Listing 15-5: Client Event Handler for Executing the Web Service

Chapter 17 - Building Real-World Web Applications Chapter 18 - 15-6: Object-Relational Mapping in .NET Listing ExecuteQuery Method


Chapter 16: ASP.NET Server Controls and Data Binding



Listing 16-1: Writing Button Click Handlers

Appendix A - Relational Databases: Some Basic Concepts Appendix B - 16-2: Commonly Used SQL Statements Listing Getting Selected Date of a Calendar Control Appendix C - ADO.NET Frequently Asked Questions IndexListing 16-3: Setting a Calendar Control's Properties List of Figures

Listing 16-4: The VisibleMonthChanged Event

List of Tables

List of Listings

Listing 16-5: Applying a Simple Template on a Repeater Control

List of Sidebars

Listing 16-6: Adding Templates to a DataList Control Listing 16-7: Adding Formatting to the Templates of a DataList Control Listing 16-8: Using the Repeater Control Listing 16-9: Data Binding in ListBox Control Listing 16-10: Data Binding in a DropDownList Control Listing 16-11: Data Binding in the TextBox,Button, and Image Controls

Listing 16-12: Data Binding in a DataList Control


Mahesh Chand and David Talbot Listing 16-13:bySetting a DataList Control's Properties

ISBN:1590590732


Listing 16-14:This Setting DataList Control's Styles text a provides extensive coverage of ADO.NET technology including ADO.NET internals, namespaces, classes, and

Listing 16-15:interfaces, Adding Update, and takes Delete, a comprehensive Cancel, and lookEdit at XML Command Handlers namespaces and classes, and how to integrate both with

Listing 16-16:ADO.NET. The Code for the Update,Delete,Cancel, and Edit Command Handlers Listing 16-17: Editable DataList Control

Table of Contents

Applied ADO.NET—Building Data-Driven Solutions Control Listing 16-18: Data Binding in a DataGrid Introduction

Listing Setting a DataGrid Control's Style Properties Chapter 1 - 16-19: ADO.NET Basics Chapter 2


Chapter 3


Listing 16-20: Rearranging a DataGrid Column's Sequence

Chapter 4 - 16-21: ADO.NET in Connected EnvironmentsHeader and Footers Listing Formatting BoundColumn's Chapter 5 - Handling ADO.NET Events

Listing The ButtonColumn Chapter 6 - 16-22: Integrating XML with ADO.NETClick Event Handler Chapter 7


Listing 16-23:DataGrid with Button Columns Chapter 8 - Constraints and Data Relations Chapter 9

ADO.NET Exception Handling Listing- 16-24: Using Template Columns

Chapter 10 - Working with the ODBC .NET Data Provider Chapter Listing 11 - 16-25: Stored Using Procedures Template and Views Columns in a DataGrid Control Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Listing Editable DataGrid Chapter 13 - 16-26: Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET

Listing 16-27: Implementing Sorting in a DataGrid Control



Chapter 17: Building Real-World Web Applications


Listing Login Button Click EventConsiderations Handler Codeand Data Binding Chapter 19 - 17-1: Mapped Objects: Performance Chapter 20 - COM Interoperability and ADO.NET

Listing 17-2: The Button Click Event Handlers


Chapter Listing 22 - 17-3: SQL Server The Register.aspx and ADO.NET: Notes Code on Performance Appendix A - Relational Databases: Some Basic Concepts

Listing Send Used Message Click Event Handler Appendix B - 17-4: Commonly SQL Statements Appendix C - ADO.NET Frequently Asked Questions

Listing 17-5: The Post Job Button Click Event Handler

Index

List ofListing Figures17-6: The Reset Fields Click Event Handler List of Tables

Listing 17-7: The Done Button Click Event Handler

List of Listings

List ofListing Sidebars 17-8: Adding Options to Post Resume Page

Listing 17-9: The Post Resume Button Click Event Handler Listing 17-10: The Done Button Click Event Handler Listing 17-11:DisplayData.aspx HTML View Listing 17-12: The FillDataGrid and Page_Load Methods Listing 17-13: The FillPartialData Method Listing 17-14: The FillDataGrid and Page_Load Methods

Listing 17-15:Resumes.aspx HTML View


ISBN:1590590732

Chapter 18:Apress Object-Relational Mapping in .NET © 2003 (928 pages)


Listing 18-1: including The VideoTapeData Object ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML and classes, Listing 18-2: namespaces The VideoTape Object and how to integrate both with ADO.NET.

Listing 18-3: The VideoTapeDataAccess Object Table Listing of Contents 18-4: The Test Case for the VideoTape Component Applied ADO.NET—Building Data-Driven Solutions Introduction Listing 18-5: The User Object in the User Component Chapter 1

- ADO.NET Basics

Listing The UserData Object in the User Component Chapter 2 - 18-6: Data Components in Visual Studio .NET Chapter 3


Chapter 4


Listing 18-7: The UserDataAccess Object in the User Component

Chapter 5 - 18-8: Handling Events Object Listing TheADO.NET UserTestCase Chapter 6


Listing Chapter 7 - 18-9: Data SelectVideosCheckedOutToUser Binding and Windows Forms Data-Bound Controls Chapter 8


Chapter 9


Listing 18-10: The VideoCheckInCheckOut Object

Chapter 10 - 18-11: Working with the ODBC .NET Data Provider Listing The VideoCheckInCheckOut Object Chapter 11 - Stored Procedures and Views

Listing Test Case for the VideoCheckInCheckOut Component Chapter 12 - 18-12: Oracle,The SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider

Chapter 19: Mapped Objects: Performance Considerations and Data Binding Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services


Listing 19-1: The Code-Behind File of the TestDataGrid Program


Chapter 19 - 19-2: Mapped Objects: Performance Considerations and Data Binding Listing The HTML Side of the TestDataGrid Page Chapter 20 - COM Interoperability and ADO.NET

Listing The HTML of the TestGridObjects Page Chapter 21 - 19-3: Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Listing 19-4: The Theoretical Shopping Cart Example


Appendix B - 19-5: Commonly Used SQL Statements Listing The HTML of the FancyBinding Page Appendix C - ADO.NET Frequently Asked Questions IndexListing 19-6: The Code-Behind Object of the FancyBinding Page List of Figures

Listing 19-7:VideoCategory and Related Objects

List of Tables

List ofListing Listings 19-8: The GetBlockedCategory Stored Procedure List of Sidebars

Listing 19-9: The Addition of the Videos() Array to the VideoCategory Object Listing 19-10: The HTML Page of the LazyLoading Page Listing 19-11: The Code-Behind Object of the LazyLoading Page Listing 19-12: The Incremental Lazy Loading Stored Procedure Listing 19-13: VideoCategoryIndexer Listing 19-14: The VideoCategoryIndexer Test Case Listing 19-15: The WeakCache Object

Building Data-Driven Solutions Chapter 20:Applied COMADO.NET: Interoperability and ADO.NET ISBN:1590590732 by Mahesh Chand and David Talbot Apress © 2003 (928 pages)

Listing 20-1: Using an ADODB Namespace to Access a Database

This text provides extensive coverage of ADO.NET technology ADO.NET internals, namespaces, classes, and Listing 20-2: including Using ADOX from Managed Code interfaces, and takes a comprehensive look at XML namespaces and classes, and how to integrate both with Listing 20-3: ADO.NET. Getting All Available Cubes from the FoodMart 2000 Database

Listing 20-4: Getting All Dimensions of a Cube Table of Contents

Listing 20-5: Getting Dimension Members


Chapter 21: Messaging - ADO.NET Basics

Chapter 1 Chapter 2


Listing Retrieving Private Queues Chapter 3 - 21-1: ADO.NET in Disconnected Environments Chapter 4


Chapter 5


Listing 21-2: Retrieving Public Queues

Chapter 6 - 21-3: Integrating XML with ADO.NET Listing Filtering Queues Based on Category, Machine Name, and Label Chapter 7 - Data Binding and Windows Forms Data-Bound Controls

Listing Creating Queue Chapter 8 - 21-4: Constraints andaData Relations Chapter 9

ADO.NET Exception Handling Listing- 21-5: Deleting a Queue

Chapter 10 - Working with the ODBC .NET Data Provider Chapter Listing 11 - 21-6: StoredGetting Procedures a Queue's and Views Properties Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers

Listing 21-7: Sending Messages to a Queue


Chapter 14 - 21-8: Developing Database Web Applications using ASP.NET Listing Receiving Messages from a Queue Chapter 15 - Using ADO.NET in Xml Web Services

Listing Sending Receiving Transactional Chapter 16 - 21-9: ASP.NET Serverand Controls and Data Binding Messages Chapter 17 - Building Real-World Web Applications

Listing 21-10: Sending Encrypted Messages



Chapter 22: SQL Server and ADO.NET: Notes on Performance


Listing The Query from SelectVideosCheckedIn, Not Optimized Chapter 22 - 22-1: SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts

Listing 22-2: An Optimized Version of the SelectVideosCheckedIn Query


Appendix C - 22-3: ADO.NET Frequently Asked Questions Listing Using sp_executesql to Execute a Database Query Index List ofListing Figures22-4: Generic Data Access Class List of Tables

Listing 22-5: User-Defined Variables

List of Listings

List ofListing Sidebars 22-6: Using the Generic Data Access Class

Appendix C: ADO.NET Frequently Asked Questions Listing C-1: Getting a Database Table Schema Using SqlCommand Listing C-2: Reading DataSet Columns and Their Data Types Listing C-3:GetPageData Method Listing C-4: Implementing Paging in ADO.NET

Listing C-5: Transactions in the OleDb Data Provider


ISBN:1590590732 by Mahesh Chand andSchema David Talbot Listing C-6: Reading a Database Programmatically


Listing C-7: Getting a provides Database's Tablescoverage from a SQL Server Database This text extensive of ADO.NET technology including ADO.NET internals, namespaces, classes, and

Listing C-8: Getting a Database Schema look at XML interfaces, and takesTable a comprehensive


Listing C-9: Selecting ADO.NET.Distinct Rows from a Database Table Listing C-10: Reading and Writing to and from the Windows Registry Table of Contents

Listing C-11: ReadingData-Driven ODBC DSNs Applied ADO.NET—Building Solutions Introduction

Listing C-12: Browse Button Click Event Handler

Chapter 1

- ADO.NET Basics

Chapter 2 - C-13: Data Components VisualClick Studio .NETHandler Listing Save ImageinButton Event Chapter 3


Listing Reading Binary Data Chapter 4 - C-14: ADO.NET in Connected Environments Chapter 5

Handling ADO.NET Events Listing- C-15: A DiffGram Format

Chapter 6


Chapter 7 - C-16: Data Binding and Windows Forms Data-Bound Controls Listing Reading DiffGrams Chapter 8

- Constraints and Data Relations Listing Reading OnlyHandling Modified Rows of a DataSet Chapter 9 - C-17: ADO.NET Exception Chapter 10 - Working with the ODBC .NET Data Provider Chapter 11 - Stored Procedures and Views Chapter 12 - Oracle, SQLXML, and Other .NET Data Providers Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding Chapter 17 - Building Real-World Web Applications Chapter 18 - Object-Relational Mapping in .NET Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 - COM Interoperability and ADO.NET Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance Appendix A - Relational Databases: Some Basic Concepts Appendix B - Commonly Used SQL Statements Appendix C - ADO.NET Frequently Asked Questions Index List of Figures List of Tables List of Listings List of Sidebars


by Mahesh Chand and David Talbot List of Sidebars

ISBN:1590590732

Apress © 2003 (928 pages) text provides extensive coverage of ADO.NET technology Chapter 1: This ADO.NET Basics including ADO.NET internals, namespaces, classes, and interfaces, and takes a comprehensive look at XML namespaces and classes, andto how For the History Buffs: How ODBC Came Beto integrate both with ADO.NET.

Chapter 2: Data Components in Visual Studio .NET Table of Contents Applied ADO.NET—Building Data-Driven Solutions IDE vs. Manual Coding Introduction

Question and Answer Chapter 1 - ADO.NET Basics Chapter 2


Chapter 3


Question and Answer

Chapter 4 - ADO.NET in Connected Environments Question and Answer Chapter 5


Chapter 6

- Integrating XML with ADO.NET Chapter 4: ADO.NET in Connected Environments

Chapter 7


Chapter 8


Chapter 9


Transactions and Concurrency in ADO.NET


Chapter 7: Data Binding and Windows Forms Data-Bound Controls



Question and Answer

Chapter 13 - Developing a Custom Data Provider Chapter 14 - Developing Database Web Applications using ASP.NET Question and Answer Chapter 15 - Using ADO.NET in Xml Web Services Chapter 16 - ASP.NET Server Controls and Data Binding

Chapter 18: Object-Relational Mapping in .NET


Paranoid Programming

Chapter 19 - Mapped Objects: Performance Considerations and Data Binding Chapter 20 -toCOM Interoperability and ADO.NET Death N-Tier Chapter 21 - Messaging Chapter 22 - SQL Server and ADO.NET: Notes on Performance

Chapter 19: Mapped Objects: Performance Considerations and Data Binding Appendix B - Commonly Used SQL Statements Appendix A - Relational Databases: Some Basic Concepts Appendix C - ADO.NET Frequently Asked Questions IndexUsing Connection Strings List of Figures

Using a Better Tree Control

List of Tables

List of Listings

Chapter 22: SQL Server and ADO.NET: Notes on Performance

List of Sidebars

How SQL Server Stores Your Data

Appendix A: Relational Databases: Some Basic Concepts What Are Deadlocks?

Appendix B: Commonly Used SQL Statements Understanding SQL Injection


ISBN:1590590732



- ADO.NET Basics

Chapter 2


Chapter 3


Chapter 4


Chapter 5


Chapter 6


Chapter 7


Chapter 8


Chapter 9



Applied ADO.NET: Building Data-Driven Solutions

Applied ADO.NET: Building Data-Driven Solutions

Applied XML Solutions

Applied XML Solutions

Applied quantum mechanics: Solutions manual

Microsoft Solutions Framework Essentials: Building Successful Technology Solutions

Microsoft SharePoint: Building Office 2003 Solutions

Building high availability Windows Server™ 2003 solutions

Building Solutions with Microsoft Commerce Server 2002

Building Web Solutions with ASP.NET and ADO.NET

Building Enterprise Solutions with Visual Studio 6

UDDI: Building Registry-based Web Services Solutions

OLAP Solutions: Building Multidimensional Information Systems

Microsoft SharePoint: Building Office 2003 Solutions

OLAP Solutions: Building Multidimensional Information Systems

Instructor Solutions - Applied Partial Differential Equations

Matrix Analysis and Applied Linear Algebra (solutions)

Solutions

Solutions

Solutions

Pro PerformancePoint Server 2007: Building Business Intelligence Solutions

Database Solutions: A step by step guide to building databases

Microsoft SharePoint: Building Office 2007 Solutions in C# 2005

Enterprise Integration Patterns: Designing, Building, and Deploying Messaging Solutions

Enterprise Integration Patterns: Designing, Building, and Deploying Messaging Solutions

OLAP Solutions: Building Multidimensional Information Systems, 2nd Edition

Microsoft SharePoint: Building Office 2007 Solutions in C# 2005

Building Web, Cloud, and Mobile Solutions with F

Microsoft SharePoint: Building Office 2007 Solutions in VB 2005

Developing Quality Metadata: Building Innovative Tools and Workflow Solutions

Developing Quality Metadata: Building Innovative Tools and Workflow Solutions

Applied ADO.NET: Building Data-Driven Solutions