IDUG NA 2025

Optimal access plans are critical for query performance, and it is the Db2 optimizer's job to choose the best one. The optimizer is very sophisticated and considers many factors while costing an access plan, but sometimes it makes mistakes, and you need to fix it quickly. This session will show you how to apply access plan tuning techniques based on queries from real Db2 customer systems. This 2025 edition of the session will cover brand new examples compared to the 2024 edition. A variety of query types will be covered, including OLTP and analytics, running on single or multiple data base partitions. You will also learn how to use the explain facility to understand how access plans work. Attend this session to learn some techniques to address a variety of access plan problems and to gain some insight into query optimization.