SPM

Find the SQL Plan Baseline for a plan operation

By Franck Pachot . If you decide to capture SQL Plan Baselines, you achieve plan stability by being conservative: if the optimizer comes with a new execution plan, it is loaded into the SQL Plan Management base, but not(…)

Enabled, Accepted, Fixed SQL Plan Baselines

By Franck Pachot . When the documentation is not always clear, I prefer to build a test case to be sure about the behavior in different context and different versions. Here is a test on SQL Plan Management to show(…)

18c dbms_xplan note about failed SQL Plan Baseline

By Franck Pachot . SQL Plan Baselines is a great feature for plan stability: you capture the plans that you accept. However, if the data model changes and the accepted plans cannot reproduce, the optimizer will come with a new(…)

Adaptive Plans and SQL Baselines

By Franck Pachot . I encountered recently an issue with Adaptive Plan and SPM. Documentations says that it works perfectly together but I remembered a presentation from Nelson Calero at UKOUG TECH15 mentioning strange behavior. I reproduced the issue and(…)

Do you use SQL Plan Baselines?

By Franck Pachot . I can hear a lot of complaints about the instability coming from the adaptive features introduced into the optimizer logic at each release. Giving more intelligence to the optimizer is very good to improve the response(…)