When I had my first Oracle DBA course some years before the start of this millennium I made a special mental note about a very common error message, ORA-00942, “table or view does not exist”.

Perl is included with the Oracle database software (SE and EE), even on Windows. I wrote this to extract the SQL statements from a trace file (generated with sql_trace=true or setting the 10046 event). A simple indentation - one tab for each level - is used to show recursive statements.

I’m a big fan of Method R, both the company and the way to optimize SQL (or any other process that can possibly be measured). The method is explained in details in their classic book Optimizing Oracle Performance. But it is hard to practice method R without a good profiler. In every installation of Oracle database the profiler tkprof is included and it does serve for some problems, but hides a lot of information from you.