Return-Path: Delivered-To: 2-oracle-l@orafaq.com Received: (qmail 21561 invoked from network); 12 Dec 2006 13:27:37 -0600 Received: from freelists-180.iquest.net (HELO turing.freelists.org) (206.53.239.180) by 69.64.49.119 with SMTP; 12 Dec 2006 13:27:34 -0600 Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 679285683B5; Tue, 12 Dec 2006 14:25:55 -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 26351-03; Tue, 12 Dec 2006 14:25:55 -0500 (EST) Received: from turing (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 4B7395683BA; Tue, 12 Dec 2006 14:25:53 -0500 (EST) Received: with ECARTIS (v1.0.0; list oracle-l); Tue, 12 Dec 2006 14:22:01 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 00E0C5680BF for ; Tue, 12 Dec 2006 14:22:01 -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 24601-01 for ; Tue, 12 Dec 2006 14:22:00 -0500 (EST) Received: from MSXVS04.trivadis.com (gromit.trivadis.com [212.249.206.2]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 2206F568062 for ; Tue, 12 Dec 2006 14:21:59 -0500 (EST) x-mimeole: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by Ecartis Subject: RE: Poor performance with Histogram Date: Tue, 12 Dec 2006 20:22:54 +0100 Message-ID: X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: Poor performance with Histogram From: "Christian Antognini" To: "Wolfgang Breitling" Cc: X-archive-position: 43064 X-ecartis-version: Ecartis v1.0.0 Sender: oracle-l-bounce@freelists.org Errors-to: oracle-l-bounce@freelists.org X-original-sender: Christian.Antognini@trivadis.com Precedence: normal Reply-to: Christian.Antognini@trivadis.com List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: oracle-l X-List-ID: oracle-l List-subscribe: List-owner: List-post: List-archive: X-list: oracle-l X-Virus-Scanned: by amavisd-new-20030616-p10 (Debian) at avenirtech.net Hi Wolfgang > What Oracle version? 10.2.0.2. But if my memory serves me right I saw the same behavior on different 9i and 10g versions. > I was thinking of bug 3929552 and could have sworn I saw it > as fixed in one of the patchsets, or I assumed that it is fixed in > 9.2.0.6 and up as there is a patch available for 9.2.0.5. I just checked Metalink. 3929552 references 3485930 which according to note 3485930.8 should be fixed in 9.2.0.6/10.1.0.3/10.2.0.1. Honestly I don't think it is a bug if data is really skewed. Therefore, I guess, the real bug was only related to that behavior, but it's not this specific behavior the problem. > So you DO get silly histograms when using "size auto" or "size > skewonly". I gave dbms_stats more credit than it deserves. Mhmm... As do you know, my opinion is different than yours. I really see many situations where SIZE AUTO/SKEWONLY does a good job. Of course this doesn't mean that the feature it's perfect! Regards, Chris -- http://www.freelists.org/webpage/oracle-l