From oracle-l-bounce@freelists.org Thu Mar 3 13:01:09 2005 Return-Path: Received: from air891.startdedicated.com (root@localhost) by orafaq.com (8.12.10/8.12.10) with ESMTP id j23J19WK014670 for ; Thu, 3 Mar 2005 13:01:09 -0600 X-ClientAddr: 206.53.239.180 Received: from turing.freelists.org (freelists-180.iquest.net [206.53.239.180]) by air891.startdedicated.com (8.12.10/8.12.10) with ESMTP id j23J17em014664 for ; Thu, 3 Mar 2005 13:01:07 -0600 Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 5EEAD7DB89; Thu, 3 Mar 2005 12:46:55 -0500 (EST) Received: from turing.freelists.org ([127.0.0.1]) by localhost (turing [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 14630-08; Thu, 3 Mar 2005 12:46:55 -0500 (EST) Received: from turing (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id D60257DC4C; Thu, 3 Mar 2005 12:46:54 -0500 (EST) Date: Thu, 03 Mar 2005 18:45:08 +0100 From: jo_holvoet@amis.com Subject: Re: Different execution plans for same query with same cost To: oracle-l@freelists.org Message-id: MIME-version: 1.0 Content-type: text/plain; charset=us-ascii X-MIMETrack: Serialize by Router on MailEU/AMI(Release 5.0.12 |February 13, 2003) at 03/03/2005 18:45:09, Serialize complete at 03/03/2005 18:45:09 Content-Transfer-Encoding: 8bit X-archive-position: 16899 X-ecartis-version: Ecartis v1.0.0 Sender: oracle-l-bounce@freelists.org Errors-To: oracle-l-bounce@freelists.org X-original-sender: jo_holvoet@amis.com Precedence: normal Reply-To: jo_holvoet@amis.com X-list: oracle-l X-Virus-Scanned: by amavisd-new-20030616-p9 (Debian) at avenirtech.net X-Spam-Checker-Version: SpamAssassin 2.60 (1.212-2003-09-23-exp) on air891.startdedicated.com X-Spam-Status: No, hits=0.3 required=5.0 tests=NO_REAL_NAME autolearn=no version=2.60 X-Spam-Level: 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 Sent by: oracle-l-bounce@freelists.org 03/03/2005 18:10 Please respond to niall.litchfield To: jo_holvoet@amis.com cc: oracle-l@freelists.org Subject: Re: Different execution plans for same query with same cost On Thu, 03 Mar 2005 17:56:58 +0100, jo_holvoet@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