Playing with cardinality and selectivity on predicates is not a common trick, though Joe Geller, David Simpson and Tony Andrews demystify it so that you can start playing with its intricacies and give a boost to the Optimizer.
You have probably heard about Db2 12 Dynamic SQL plan stability already. However, before you decide to activate it, you should learn more first. This article is going to help you on your journey to stabilize your dynamic world.
One of the most common maintenance activities performed on a Db2 LUW database is running Runstats on tables and indexes. Accurate database statistics are vital for the Db2 Optimizer to produce the most optimal plans.
Whenever a performance problem arises, the database takes the blame, but is that really true? This article will provide a hand's on, step by step approach to determine where the problem is. "Guilty Until Proven Innocent"
By now, most DB2 for LUW users have probably heard about the release of DB2 11.1 that became available in June of this year. In this article I’d like to provide more information on some performance optimizations in DB2 11.1 that will benefit queries accessing both row and column-organized tables.