Re: CBO Question - Is 'monitoring' used to calculate query plan?
From: Jared Still <jkstill_at_gmail.com>
Date: Thu, 8 Jan 2009 16:55:26 -0800
Message-ID: <bf46380901081655jc9a4843s938f73f4264d265_at_mail.gmail.com>
On Thu, Jan 8, 2009 at 1:16 PM, Greg Rahn <greg_at_structureddata.org> wrote:
Date: Thu, 8 Jan 2009 16:55:26 -0800
Message-ID: <bf46380901081655jc9a4843s938f73f4264d265_at_mail.gmail.com>
On Thu, Jan 8, 2009 at 1:16 PM, Greg Rahn <greg_at_structureddata.org> wrote:
> On Thu, Jan 8, 2009 at 12:11 PM, Jared Still <jkstill_at_gmail.com> wrote:
> > It still doesn't answer the question however of "Does the CBO use the
> stats
> > seen in all_tab_modifications for query plans?"
>
> I'm quite certain the answer is no - it is only used by dbms_stats to
> determine stale objects.
>
Thanks Greg, that's what I wanted to know.
I could probably devise a test for it, but asking someone who knows is often sufficient. :)
Jared
-- http://www.freelists.org/webpage/oracle-lReceived on Thu Jan 08 2009 - 18:55:26 CST