Oracle FAQ Your Portal to the Oracle Knowledge Grid
HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US
 

Home -> Community -> Mailing Lists -> Oracle-L -> Re: Different execution plans for same query with same cost

Re: Different execution plans for same query with same cost

From: <jo_holvoet_at_amis.com>
Date: Thu, 03 Mar 2005 18:45:08 +0100
Message-id: <OFD9B55C39.D0087A21-ONC1256FB9.0061334D@eu.amis.com>


No FGAC or RLS, but cursor_sharing=force (sigh). And it is the same query run from the same session. I just sat there pushing the pretty little "execute" button in SQL Navigator :)

mvg/regards

Jo

Niall Litchfield <niall.litchfield_at_gmail.com> Sent by: oracle-l-bounce_at_freelists.org
03/03/2005 18:10
Please respond to niall.litchfield  

        To:     jo_holvoet_at_amis.com
        cc:     oracle-l_at_freelists.org
        Subject:        Re: Different execution plans for same query with same cost


On Thu, 03 Mar 2005 17:56:58 +0100, jo_holvoet_at_amis.com <jo_holvoet_at_amis.com> wrote:

I'm not sure that I believe that the query *is* the same. ...
Are there perhaps different literal values in the query? different case or capitalisation, FGAC going on if that was around in 8i (think it was).
...
That all said if when evaluating execution plans the cost the CBO arrives at is not better than the best it already has it will not choose the second plan to be evaluated. (not sure in the absence of the ordered or other hints what drives the order of evaluation - Wolfgang might know).

--

Niall Litchfield
Oracle DBA
http://www.niall.litchfield.dial.pipex.com
--

http://www.freelists.org/webpage/oracle-l

--

http://www.freelists.org/webpage/oracle-l Received on Thu Mar 03 2005 - 13:01:09 CST

Original text of this message

HOME | ASK QUESTION | ADD INFO | SEARCH | E-MAIL US