From Access to SQL Server

Transcription

1 IURQWIP3DJHL7XHVGD\$XJXVW30 From Access to SQL Server RUSSELL SINCLAIR

2 IURQWIP3DJHLLL7XHVGD\$XJXVW30 Contents at a Glance Introduction... xi Chapter 1 What Every Access Programmer Needs to Know about SQL Server...1 Chapter 2 Why Migrate?...25 Chapter 3 Planning the Upgrade...37 Chapter 4 The Microsoft Wizard...59 Chapter 5 Data Transformation Services...99 Chapter 6 Using SQL Server Chapter 7 Using SQL Server Chapter 8 Enabling Data Access Chapter 9 Stored Procedures Chapter 10 Getting Connected Chapter 11 Coding with SQL Server Data Chapter 12 Optimizing Access for SQL Server Appendix A Selected Tables Index iii

3 IURQWIP3DJHY7XHVGD\$XJXVW30 Contents Introduction... xi Chapter 1 What Every Access Programmer Needs to Know about SQL Server...1 SQL Server Architecture... 1 Transact-SQL... 3 Main Database Components... 4 Database Files... 5 Security Modes... 5 System Databases... 6 Database Objects... 8 Using Enterprise Manager (SQL 6.5) Viewing Data Using Enterprise Manager (SQL 7.0) Viewing Data Finding Information Chapter 2 Why Migrate?...25 What Is Migrating? Access versus SQL Server Size Constraints Transferring Data Multi-User Constraints Maintenance and Administration Replication Cost Reasons to Migrate Size Number of Users Network Traffic Response Issues Maintenance and Administration Replication v

4 IURQWIP3DJHYL7XHVGD\$XJXVW30 Reasons Not to Migrate Size Organization of Data User Connectivity Cost Migration Considerations Chapter 3 Planning the Upgrade...37 Planning How Data Will Be Accessed Data Access Methods Analyzing Objects Tables Queries Forms Reports Macros Modules General Considerations Documentation Chapter 4 The Microsoft Wizard...59 Introducing the Upsizing Wizard Obtaining the Wizard Preparing to Use the Wizard Running the Wizard Evaluating the Wizard What the Wizard Does and Doesn t Do Well Recommendations Chapter 5 Data Transformation Services...99 What Is Data Transformation Services? DTS Architecture Relevance to an Access Migration Accessing DTS Scripting Using DTS with the Upsizing Wizard A Final Word about DTS vi

5 IURQWIP3DJHYLL7XHVGD\$XJXVW30 Contents Chapter 6 Using SQL Server Using SQL Server Managing Devices Managing Databases Managing Logins Managing Database Objects Other Tools A Special Note on Security Moving On Chapter 7 Using SQL Server Using SQL Server Managing Databases Managing Logins Managing Database Objects Other Tools A Special Note on Security Moving On Chapter 8 Enabling Data Access Tables Choosing the Appropriate Data Type Indexing Timestamps Views Creating Views Why Use Views An Ounce of Prevention Chapter 9 Stored Procedures Using Stored Procedures What Stored Procedures Can Do Stored Procedure Types Components Stored Procedure Syntax Coding Stored Procedures vii

6 IURQWIP3DJHYLLL7XHVGD\$XJXVW30 Migrating to Stored Procedures Migrating Queries Migrating Macros Migrating Code Examples Testing SQL Power Tools Chapter 10 Getting Connected Choosing a Connection Method ODBC Access Database Projects Chapter 11 Coding with SQL Server Data Data Coding Choices Data Access Objects (DAO) ODBCDirect ActiveX Data Objects (ADO) Choosing a Data Access Technology Using DAO to Manage Local Objects Working with Data The Choice Is Yours viii Chapter 12 Optimizing Access for SQL Server Reducing Data Transfers Filtering Data on the Server Bound Controls Access Settings Client-Side Processing Increasing Throughput SQL Database Design Access Database Design A Plan for the Future Tip #1: Use Queries to Enhance Security Tip #2: Perform Bulk Updates Using Stored Queries Tip #3: Use Parameters Now Tip #4: Increase Maintainability with Stored Queries Tip #5: Use ADO for Coding against Data A Final Word

7 IURQWIP3DJHL[7XHVGD\$XJXVW30 Contents Appendix A Selected Tables SQL Server Data Types Microsoft Access ODBC Registry Settings Index ix

8 IURQWIP3DJH[L7XHVGD\$XJXVW30 Introduction There is considerably more TO MIGRATING AN ACCESS DATABASE TO SQL SERVER THAN Microsoft would have you believe. The fact that you are reading this introduction leads me to believe that you already know this, and that you are looking for more answers. This book provides those answers. You may be wondering right now if this book is for you. Let me help you answer that question. This book is written primarily for Microsoft Access developers those of you who create applications using Microsoft Access both as the database that stores the data, and as the development environment in which the user interface is created and maintained. The main purpose of this book is to aid Access developers in understanding how to modify their database and application, so that the data side of the application can be moved to SQL Server. All of the techniques described to access data and the information on how to plan the move assume you are migrating the back-end database only. Although this book does concentrate a great deal on Access as an interface development environment, Visual Basic developers and others may find this information helpful because many of the concepts can easily be applied to pure Visual Basic applications in which the database itself is being moved from Access to SQL Server. In writing this book, I made a few assumptions about you, the reader, and your experience developing applications with Microsoft Access. I made the assumption that you have experience creating databases and user interfaces in Microsoft Access and know how to make the two cooperate. This means that you know how to design tables, queries, forms, and reports in the IDE. I assumed that you have at least tried to create an Access application that has separate database files for the back-end data and the front-end interface. It is not required but I would recommend that you understand at least how to do this. Finally, I made the assumption that you have done at least a little Visual Basic for Applications (VBA) programming. This is because the vast majority of Access development requires at least some rudimentary VBA programming. Although you can get by without needing any VBA code, Access really shines when you start to program it using VBA. Where's the CD? Okay, you caught me. This is probably one of the few application-specific books you have picked up in recent years that doesn t come with a CD (or a least a diskette). You may be wondering why. When I originally started to write this book, I had every intention of creating a CD that you could use to follow the techniques described in each chapter. xi

9 IURQWIP3DJH[LL7XHVGD\$XJXVW30 However, as I progressed through the book, I realized that although I could go through the specifics of the sample database I created, it probably would not apply to your application. I didn t want to overload you with information on a sample database that did not teach you what you needed to know. Instead, I have concentrated on including the information that I have learned from many Access to SQL migrations. Any sample database that included all of the problems you should watch out for in your migration would seem like such a bad design to begin with that it would be doomed to fail no matter what. However, there is a sample database that you can download from the Apress Web site at that includes all of the sample code listed in the book, along with one or two other useful functions. All of the code I have used in the book is complete in the text, there is nothing missing from the code that would prevent it from working on your database. I hope to keep this sample up-to-date for the next while, incorporating suggestions and questions from readers as they come in. It is always nicer when things improve over time. Feedback and Information The latest information about the book and a complete list of links that I think could help you in your migration can be found at the Apress Web site at The downloads for the book will also be available from this site; just check out my section on the site. Any questions, feedback, or other communications related to this book are welcome. You can reach me through at FromAccessToSQL@home.com or russellsinclair@home.com. Either account will go directly to me. xii

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