DB2 SQL Tuning Tips for Z/OS Developers

The Definitive Solutions-Oriented Guide to IBM® DB2® for z/OS®: Now Fully Updated for Both v9 and v10!

The largest database tuning performance gains can often be obtained from tuning application code, and applications that use SQL to retrieve data are the best candidates for tuning. This well-organized, easy-to-understand reference brings together more than 100 SQL-related skills and techniques that any developer can use to build and optimize DB2 applications for consistently superior performance.

DB2 tuning expert Tony Andrews (“Tony the Tuner”) draws on more than 20 years of DB2-related experience, empowering you to take performance into your own hands, whether you’re writing new software or tuning existing systems. Tony shows you exactly how to clear bottlenecks, resolve problems, and improve both speed and reliability.

This book fully reflects the latest SQL programming best practices for DB2 V9 and DB2 V10 on z/OS: techniques that are taught in no other book and are rarely covered in general DB2 SQL courses. Drawing on his extensive consulting experience and highly praised training with Themis Inc., Tony also presents practical checklists and an invaluable 15-step methodology for optimizing virtually any DB2 application.

Coverage includes

• Empowering developers on knowing what to do and where to look in resolving performance problems in queries or programs
• Providing many programming and SQL coding examples
• Establishing standards and guidelines that lead to high-performance SQL
• Implementing time-efficient code walkthroughs to ensure that your standards are followed
• Focusing on the small number of SQL statements that consume the most resources
• Identifying simple solutions that deliver the most sizable benefits
• Optimizing performance by rewriting query predicates more efficiently
• Providing a better understanding of SQL optimization and Runstat statistics
• Recognizing opportunities to tweak your code more effectively than the Optimizer
• Optimizing SQL code with COBOL applications
• Efficiently checking for the existence of data, rows, or tables
• Using Runstats’ newest capabilities to consistently optimize paths to data

This well-organized, easy-to-understand reference brings together 102 SQL-related skills and techniques that any developer can use to build DB2 applications that deliver consistently superior performance. Legendary DB2 tuning expert Tony Andrews ("Tony the Tuner") draws on more than 23 years of DB2-related experience, empowering developers to take performance into their own hands - whether they're writing new software or tuning existing systems. Andrews reveals the hidden truth about why DB2 queries, programs, and applications often perform poorly, and shows developers exactly how to clear the bottlenecks and resolve the problems. He fully reflects the latest DB2 SQL programming best practices up to and including DB2 V9 and DB2 V10 on z/OS: techniques that are taught in no other book, and are rarely covered in typical DB2 training courses. Drawing on his extensive consulting experience and highly-praised live training courses, he also presents an invaluable 10-step methodology for tuning virtually any DB2 query. Coverage includes: * Systematically identifying and fixing poorly coded programs or improperly coded SQL statements * Understanding and taking advantage of Runstat options * Adding or altering indexes * Understanding and leveraging the latest SQL standards and guidelines * Effectively utilizing Existence Checking, and much more

Tony Andrews has more than 23 years’ experience in the development of IBM DB2 relational database applications. Most of this time, he has provided development and consulting services to Fortune 500 companies and government agencies. Tony has written literally thousands of queries and programs during his development years, and he has also served as a DB2 database analyst. For the past 10 years, Tony has been splitting his time between consulting engagements and training. His main focus is to teach today’s developers the ways of RDMS application design, development, and SQL programming— always with a special emphasis on improving performance. Tony’s training, consulting, and speaking engagements are through his employer, Themis, Inc., an onsite and virtual instructor-led, hands-on IT training company recognized internationally. It offers more than 400 IT courses and helps to support International DB2 Users Group North America (IDUG NA) and Europe, Middle East, and Africa (IDUG EMEA), along with many DB2 user groups.

Tony is a current IBM champion and regular lecturer at industry conferences and local user groups. You may have seen him present at such events as IDUG NA and EMEA. He is well known for his “Top 25+ Tuning Tips for Developers” presentation.

Tony graduated from Ohio State University with a major in business and a minor in mathematical statistics. He currently resides in Dublin, Ohio.

1. SQL Optimization Top 100+

2. DB2 SQL Hints

3. SQL Standards and Guidelines

4. SQL Program Walkthroughs

5. Existence Checking

6. Runstats

7. Ten Steps to Tuning a Query

Appendix A. Predicate Rewrite Examples

Appendix B. DB2 SQL Terminology