Received: from maia.hub.org (maia-3.hub.org [200.46.204.243]) by mail.postgresql.org (Postfix) with ESMTP id 148DC1337B80 for ; Wed, 13 Apr 2011 17:19:18 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.243]) (amavisd-maia, port 10024) with ESMTP id 30683-08 for ; Wed, 13 Apr 2011 20:19:11 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from mail.gransy.com (mail.gransy.com [82.208.29.194]) by mail.postgresql.org (Postfix) with ESMTP id E78441337BB4 for ; Wed, 13 Apr 2011 17:19:10 -0300 (ADT) Received: from localhost (localhost [127.0.0.1]) by mail.gransy.com (Postfix) with ESMTP id BA67F2E5A0A1 for ; Wed, 13 Apr 2011 22:19:10 +0200 (CEST) Received: from mail.gransy.com ([127.0.0.1]) by localhost (nathalia.gransy.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id e0uX312K-56o for ; Wed, 13 Apr 2011 22:19:10 +0200 (CEST) Received: from [192.168.1.221] (ip-94-112-0-189.net.upcbroadband.cz [94.112.0.189]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.gransy.com (Postfix) with ESMTPSA id A61D92E5A09F for ; Wed, 13 Apr 2011 22:19:10 +0200 (CEST) Message-ID: <4DA6053E.3090200@fuzzy.cz> Date: Wed, 13 Apr 2011 22:19:10 +0200 From: Tomas Vondra User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.13) Gecko/20101219 Lightning/1.0b3pre Thunderbird/3.1.7 MIME-Version: 1.0 To: pgsql-performance@postgresql.org Subject: Re: how explain works to Mr Nathan Boley References: <64088.55807.qm@web38604.mail.mud.yahoo.com> <52482.84679.qm@web38603.mail.mud.yahoo.com> In-Reply-To: <52482.84679.qm@web38603.mail.mud.yahoo.com> X-Enigmail-Version: 1.1.1 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.9 tagged_above=-10 required=5 tests=BAYES_00=-1.9 X-Spam-Level: X-Archive-Number: 201104/194 X-Sequence-Number: 43256 Dne 12.4.2011 01:22, Radhya sahal napsal(a): > Thanks Mr Nathan Boley , > i want these equations to solve thsese equtions of parameters and total > time in order to get each paramter formula > i need these formula in my experiments is very important to know the > rate for each parameter in total cost for plan. > Best > Radhya.. I don't think those equations are fully documented outside the source code. If you really need the exact formulas, you'll have to dig into the source codes and search there. regards Tomas