IDUG NA 2026

In the world of Db2 for z/OS, SQL performance tuning is one of the most critical and often most complex of DBA tasks. While static SQL has long been the standing order for traditional mainframe applications, the growing use of dynamic SQL - driven by modern applications, APIs, and distributed workloads - has changed the tuning game.Dynamic SQL’s agility and flexibility introduces a new layer of complexity that can hinder performance if not well managed and cause inconsistent performance and even be unpredictable. Dynamic SQL is becoming more prevalent as agile development and hybrid workloads become the norm. But with the flexibility of dynamic SQL comes responsibility - DBAs must adapt and develop new ways of monitoring and tuning dynamic workloads in real-time and across the application lifecycle. Colin Oakhill will share a proven approach to bring order to chaos by giving DBAs the visibility, control, and insight they need to ensure that dynamic SQL performs efficiently and predictably. Just like long-time DBAs are used to with static SQL.

This presentation will demonstrate how to find, analyze and tune the top 40 expensive queries. Special emphasis will be on finding the cursors that could benefit from multi-row fetch. In addition, discussions on designing perfect indexes, MQTs and AQTs, along with manual query rewrite, SQL exploitation and most important, proper use.