Optimizer

Oracle system statistics: Display AUX_STATS$ with calculated values and formulas

By Franck Pachot . System statistics can be gathered in NOWORKLOAD or WORKLOAD mode. Different values will be set depending on that and the others will be calculated – derived from them. We can see defined values from SYS.AUX_STATS$(…)

SQL Patch: Another way to change the plan without changing the code

Recently, at a customer site, I faced a performance issue. However, as often the statement is embedded in the application so it’s not possible to rewrite the query. In this blog post, we’ll change the execution plan to solve the(…)

Oracle 12c Adaptive Plan & inflection point

By Franck Pachot . The Oracle 12c Adaptive Plan feature was already presented by Nicolas Jardot in OOW 2013: Solving customer issues with the 12c Optimizer. I recently had to answer several questions about its behavior at execution(…)