Re: Expensive SQL
From: dombrooks <dombrooks_at_hotmail.com>
Date: Tue, 23 Aug 2011 08:53:14 -0700 (PDT)
Message-ID: <9e5f0c73-6251-47e1-9907-07d1bca42bfb_at_b14g2000vbg.googlegroups.com>
BTW whilst that bug description mentions baseline capture as the area of the bug (or it did when I had cause to have it patched), that's only part of it.
It's very much baseline usage that is affected as well.
Date: Tue, 23 Aug 2011 08:53:14 -0700 (PDT)
Message-ID: <9e5f0c73-6251-47e1-9907-07d1bca42bfb_at_b14g2000vbg.googlegroups.com>
BTW whilst that bug description mentions baseline capture as the area of the bug (or it did when I had cause to have it patched), that's only part of it.
It's very much baseline usage that is affected as well.
What that bug does illustrate is some of the recursive work involved with baselines even with capture off and usage on.
So whilst the patch fixes the original issues of the full table scans
against the sqlobj$auxdata and sqlobj$ objects, using INDEX hints by
the look of it,
just the execution of a baselined sql statement involves a couple of
look ups against these tables and merge operations to update all the
associated metadata.
Received on Tue Aug 23 2011 - 10:53:14 CDT