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

Interpreting db2exfmt output


In the previous recipe, we discussed how to use different explain utilities. db2exfmt is the most commonly-used utility for troubleshooting a performance problem. This utility gives very detailed information captured in EXPLAIN tables in the form of an ASCII text report. This report contains textual information, as well as the access plan in a graphical format, which is extremely useful for query analysis. In this recipe, we will discuss how to interpret the results from the db2exfmt utility.

How to do it...

As mentioned in the previous recipe, the output of the db2exfmt tool contains very detailed information about the query execution plan. In this section, we will discuss how to interpret each section.

  1. 1. Verifying the database information: The top section of the db2exfmt output contains DB2 version information, and the time when the db2exfmt tool was run.

  2. 2. Check the database context area: This section contains the configuration parameter values that have...