Lesson Summary
- Examine how an SQL plan becomes invalidated in the SQL Plan Cache and recompiled execution plans.
- Utilize the Plan Decision Recorder to identify the reasons behind SQL plan invalidations and recompilations.
- Investigate object definition changes by checking invalidation reasons and dependent objects to pinpoint performance impacts.
- Monitor table statistics changes to detect when recompilation occurs due to significant row count variations.
- Address parameterized query issues by analyzing pre-compiled plans in the Plan Decision Recorder to uncover original invalidation reasons.
- Employ the Plan Stability feature to maintain consistent query performance across SAP HANA database upgrades.