X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 26E725298D for ; Mon, 11 Jul 2005 20:47:58 -0300 (ADT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 74667-09 for ; Mon, 11 Jul 2005 23:47:55 +0000 (GMT) Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by svr1.postgresql.org (Postfix) with ESMTP id 637D452987 for ; Mon, 11 Jul 2005 20:47:54 -0300 (ADT) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.13.1/8.13.1) with ESMTP id j6BNloXr012962; Mon, 11 Jul 2005 19:47:50 -0400 (EDT) To: "jobapply" Cc: pgsql-performance@postgresql.org Subject: Re: Sorting on longer key is faster ? In-reply-to: <20050709183842.2EABF52820@svr1.postgresql.org> References: <20050709183842.2EABF52820@svr1.postgresql.org> Comments: In-reply-to "jobapply" message dated "Sat, 09 Jul 2005 22:38:40 +0400" Date: Mon, 11 Jul 2005 19:47:50 -0400 Message-ID: <12961.1121125670@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.006 tagged_above=0 required=5 tests=AWL X-Spam-Level: X-Archive-Number: 200507/116 X-Sequence-Number: 13357 "jobapply" writes: > The 2 queries are almost same, but ORDER BY x||t is FASTER than ORDER BY x.. > How can that be possible? Hmm, how long are the x values? Is it possible many of them are TOASTed? regards, tom lane