Book Image

IBM DB2 9.7 Advanced Application Developer Cookbook

Book Image

IBM DB2 9.7 Advanced Application Developer Cookbook

Overview of this book

With lots of new features, DB2 9.7 delivers one the best relational database systems in the market. DB2 pureXML optimizes Web 2.0 and SOA applications. DB2 LUW database software offers industry leading performance, scale, and reliability on your choice of platform on various Linux distributions, leading Unix Systems like AIX, HP-UX and Solaris and MS Windows platforms. This DB2 9.7 Advanced Application Developer Cookbook will provide an in-depth quick reference during any application's design and development. This practical cookbook focuses on advanced application development areas that include performance tips and the most useful DB2 features that help in designing high quality applications. This book dives deep into tips and tricks for optimized application performance. With this book you will learn how to use various DB2 features in database applications in an interactive way.
Table of Contents (15 chapters)
IBM DB2 9.7 Advanced Application Developer Cookbook
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface

Using dynamic SQL in stored procedures


Dynamic SQL is used when the SQL statement is not known at compile time. In such cases, we use PREPARE and EXECUTE statements to execute a dynamic SQL, where we get the complete SQL statement at runtime. The prepared statement is based on either a host variable or a string expression. At runtime, we make this value available for DB2 to process it. We can implement dynamic SQL in stored procedures in the same manner as in other applications. In this recipe, we will focus on using dynamic SQL in stored procedures.

How to do it...

Executing an SQL statement dynamically: To execute an SQL statement dynamically, we need to first prepare it and then execute it. The statement can be prepared from a declared variable or directly from an SQL statement.

The following example prepares and executes an UPDATE statement on the EMPLOYEE table, based on input parameter value:

  1. 1. Define the input and output parameters of the procedure along with any optional clauses...