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 CUR_COMMIT concurrency control isolation level


DB2 9.7 introduces a new isolation level called Currently Committed (CC) , wherein readers don't block writers, and writers don't block readers. In earlier versions of DB2, there were chances that a reader would block a writer and a writer would block a reader.

The isolation level currently committed will be set at the database level using the CUR_COMMIT parameter. When one creates a database on DB2 9.7, by default, CUR_COMMIT will be ON, and in case if one migrates the database from an older version on to DB2 9.7, one has to update the configuration parameter explicitly.

Getting ready

To update the database configuration parameter CUR_COMMIT, one should have the SYSADM or the DBADM privilege.

How to do it...

In this section, we'll look at extracting the current database configuration parameter CUR_COMMIT, and update it, if it's not active. We will also look at the ways of overriding the database-level parameter at the application layer...