Oracle Index Parallel Degree Fix After Parallel Creation or Rebuild | Tanel Poder Consulting

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Oracle Index Parallel Degree Fix After Parallel Creation or Rebuild | Tanel Poder Consulting

Back in 2007, my third blog entry was about a parallel index building gotcha, a warning about building & rebuilding indexes in parallel. After completing the build, Oracle left the parallel degree in place for that index in data dictionary. Thus, after building a great new index over some weekend, many of your OLTP queries could have picked a parallel plan afterwards!
Whenever creating/rebuilding any indexes, I had a habit of writing up both the CREATE INDEX . - Linux, Oracle, SQL performance tuning and troubleshooting - consulting & training.

https://tanelpoder.com/posts/index-parallelism-fix/

[ls-lrth]

Hi Tanel,
Interesting post. How were you able to find this out? Is there an official documentation detailing this fix?

[tanelpoder]

I sometimes just check what new parameters/fix controls have shown up in V$SESSION_FIX_CONTROL etc... I've written about before (link below). Now there's also a useful Oracle website for diffing various parameter/fix changes across patch versions (link below)

• https://tanelpoder.com/posts/scripts-for-drilling-down-into-unknown-optimizer-changes/
• https://oradiff.oracle.com