Oracle optimizer

Jonathan Lewis @ dbi services: Oracle Optimizer workshop

Last week, Oracle Ace Director Jonathan Lewis held an Oracle Optimizer Workshop at dbi services BaselArea. I would like to share some of the key learnings of this really interesting exchange I experienced together with my colleagues.

A SQL statement is slow and suddenly fast? Have a look at “Cardinality Feedback”!

Discussing with some tuning gourous we were made aware about this feature. It is not so far from the adaptive cursor sharing perfectly described in  Chris's blog : http://antognini.ch/papers/BindVariablePeeking_20090718.pdfThis feature, compares the real execution(…)

How to avoid strange figures in the Oracle optimizer system statistics

Have you ever noticed strange figures while collecting the Oracle optimizer system statistics ? If so, you need to provide the optimizer with the correct number. In this posting, I will show you how.