X-Original-To: pgsql-sql-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.2]) by svr1.postgresql.org (Postfix) with ESMTP id E6C6CD1E929 for ; Thu, 18 Mar 2004 18:39:21 +0000 (GMT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (neptune.hub.org [200.46.204.2]) (amavisd-new, port 10024) with ESMTP id 65324-07 for ; Thu, 18 Mar 2004 14:39:17 -0400 (AST) Received: from davinci.ethosmedia.com (server228.ethosmedia.com [209.128.84.228]) by svr1.postgresql.org (Postfix) with ESMTP id 294CED1D549 for ; Thu, 18 Mar 2004 14:39:11 -0400 (AST) Received: from [63.195.55.98] (HELO 192.168.1.29) by davinci.ethosmedia.com (CommuniGate Pro SMTP 4.1.8) with ESMTP id 4647586; Thu, 18 Mar 2004 10:40:29 -0800 From: Josh Berkus Reply-To: josh@agliodbs.com Organization: Aglio Database Solutions To: sad , pgsql-sql@postgresql.org Subject: Re: perfomance question Date: Thu, 18 Mar 2004 10:38:30 -0800 User-Agent: KMail/1.5.4 References: <200403180941.45591.sad@bankir.ru> In-Reply-To: <200403180941.45591.sad@bankir.ru> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200403181038.30116.josh@agliodbs.com> X-Virus-Scanned: by amavisd-new at postgresql.org X-Archive-Number: 200403/195 X-Sequence-Number: 17294 Sad, > what are perfomance difference bitween > a) update t1 set f1 = 'x', f2 = 'y'; > b) update t1 set f1 = 'x', f2 = f2; > c) update t1 set f1 = 'x'; > ? Not a lot. Why don't you try it? -- -Josh Berkus Aglio Database Solutions San Francisco