X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by postgresql.org (Postfix) with ESMTP id B695B9DCC80 for ; Tue, 29 Nov 2005 08:17:06 -0400 (AST) Received: from postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 21583-05 for ; Tue, 29 Nov 2005 08:17:07 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey- Received: from mail.metronet.co.uk (mail.metronet.co.uk [213.162.97.75]) by postgresql.org (Postfix) with ESMTP id 241C09DCBF7 for ; Tue, 29 Nov 2005 08:17:03 -0400 (AST) Received: from mainbox.archonet.com (84-51-143-99.archon037.adsl.metronet.co.uk [84.51.143.99]) by smtp.metronet.co.uk (MetroNet Mail) with ESMTP id AC6D5408E5E; Tue, 29 Nov 2005 12:16:13 +0000 (GMT) Received: from [192.168.1.17] (client17.office.archonet.com [192.168.1.17]) by mainbox.archonet.com (Postfix) with ESMTP id 0B2C315EA4; Tue, 29 Nov 2005 12:16:21 +0000 (GMT) Message-ID: <438C4694.3010502@archonet.com> Date: Tue, 29 Nov 2005 12:16:20 +0000 From: Richard Huxton User-Agent: Thunderbird 1.5 (X11/20051025) MIME-Version: 1.0 To: "energumen@buaa.edu.cn" Cc: pgsql-performance Subject: Re: index auto changes after copying data ? References: <20051129065944.8294B37F78@mx2.buaa.edu.cn> In-Reply-To: <20051129065944.8294B37F78@mx2.buaa.edu.cn> Content-Type: text/plain; charset=GB2312 Content-Transfer-Encoding: 7bit X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, score=0 required=5 tests=[AWL=0.000] X-Spam-Score: 0 X-Spam-Level: X-Archive-Number: 200511/551 X-Sequence-Number: 15808 energumen@buaa.edu.cn wrote: > I know in mysql, index will auto change after copying data > Of course, index will change after inserting a line in postgresql, but what about copying data? The index will (of course) know about the new data. You might want to ANALYZE the table again after a large copy in case the statistics about how many different values are present changes. -- Richard Huxton Archonet Ltd