Comments on: dbms_xplan.display_sql_plan_baseline can also lie !

By: Marie Raillard

Marie Raillard — Wed, 08 Aug 2012 15:07:18 +0000

Since 11.2.0.2, REPRODUCED column from DBA_SQL_PLAN_BASELINE can help
-> REPRODUCED : Indicates whether the optimizer was able to reproduce the plan (YES) or not (NO).

By: Sergey

Sergey — Thu, 26 Jul 2012 13:13:47 +0000

Thanks. Very useful info.

By: Sergey

Sergey — Thu, 26 Jul 2012 13:12:06 +0000

Thanks! Great Kerry’s scripts usage examples.

By: anthonydba

anthonydba — Mon, 14 May 2012 20:19:22 +0000

I guess it’s exact_matching_signature=signature.
I have also noticed that the sql plan baselines aren’t being used after a table was altered in PeopleSoft applications(I am sure you must be aware of how PeopleSoft application designer generates alter scripts).In my case,I did a test w/o altering the table/index structure by choosing “alter even if no changes” option from application designer’s build options.

Thanks
Antony

By: Kerry Osborne’s Oracle Blog » Blog Archive » Displaying SQL Baseline Plans – Kerry Osborne’s Oracle Blog

Thu, 15 Mar 2012 20:33:23 +0000

[...] After I wrote this up I realized that Coskan Gundogar had already blogged about it here (pretty thoroughly I might add). So please see his post as well. By the way, I do agree with his [...]

By: coskan

coskan — Tue, 16 Aug 2011 18:20:04 +0000

Thanks for the comment. They are all same. sql_plan_baselines2.sql is actually query v$sql and dba_sql_plan_baseline via force_matching_signature and signature columns

By: mdinh

mdinh — Tue, 16 Aug 2011 13:04:52 +0000

I am curious. Is the signature from dba_sql_plan_baselines the same for both?

By: barfo rama

barfo rama — Mon, 15 Aug 2011 23:13:18 +0000

I’m wondering if this behavior stems from handling the possibility of indices being deferred, rebuilt online or otherwise temporarily unavailable. You wouldn’t want to totally invalidate a baseline due to a temporary situation. You would want to be explicit about it though, I’d think a view that included info from when these things happen should be available.

Do you see the same effect when you, say, change an index to novalidate?