X-Original-To: pgsql-hackers-postgresql.org@localhost.postgresql.org Received: from localhost (av.hub.org [200.46.204.144]) by postgresql.org (Postfix) with ESMTP id 8BA409DCCC4 for ; Thu, 16 Feb 2006 00:51:12 -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 16577-04 for ; Thu, 16 Feb 2006 00:51:11 -0400 (AST) X-Greylist: from auto-whitelisted by SQLgrey- Received: from floppy.pyrenet.fr (floppy.pyrenet.fr [194.116.145.2]) by postgresql.org (Postfix) with ESMTP id 41EC69DCCC3 for ; Thu, 16 Feb 2006 00:51:10 -0400 (AST) Received: by floppy.pyrenet.fr (Postfix, from userid 106) id 874BF3093C; Thu, 16 Feb 2006 05:51:08 +0100 (MET) From: "Qingqing Zhou" X-Newsgroups: pgsql.hackers Subject: Re: qsort again (was Re: [PERFORM] Strange Create Index behaviour) Date: Thu, 16 Feb 2006 12:47:50 +0800 Organization: Hub.Org Networking Services Lines: 17 Message-ID: References: <43F38867.6010701@gpdnet.co.uk> <19510.1140036968@sss.pgh.pa.us> <19779.1140038874@sss.pgh.pa.us> <43F39E53.1020009@gpdnet.co.uk> <20781.1140046109@sss.pgh.pa.us> <23107.1140064820@sss.pgh.pa.us> X-Complaints-To: usenet@news.hub.org X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 6.00.2800.1506 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1506 To: pgsql-hackers@postgresql.org X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, score=0.161 required=5 tests=[AWL=0.161] X-Spam-Score: 0.161 X-Spam-Level: X-Archive-Number: 200602/605 X-Sequence-Number: 79743 "Tom Lane" wrote > "Qingqing Zhou" writes: > > By "did this 100 times" do you mean generate a sequence of at most > > 200000*100 numbers, and for every 200000 numbers, the first half are all > > zeros and the other half are uniform random numbers? > > No, I mean I ran the bit of SQL script I gave 100 separate times. > I must misunderstand something here -- I can't figure out that why the cost of the same procedure keep climbing? Regards, Qingqing