Received: from maia.hub.org (maia-2.hub.org [200.46.204.251]) by mail.postgresql.org (Postfix) with ESMTP id 47F7B1337B80 for ; Tue, 30 Nov 2010 13:57:48 -0400 (AST) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.251]) (amavisd-maia, port 10024) with ESMTP id 32031-06 for ; Tue, 30 Nov 2010 17:57:41 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from out01.mta.xmission.com (out01.mta.xmission.com [166.70.13.231]) by mail.postgresql.org (Postfix) with ESMTP id CC4E81337B81 for ; Tue, 30 Nov 2010 13:57:40 -0400 (AST) Received: from in01.mta.xmission.com ([166.70.13.51]) by out01.mta.xmission.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.69) (envelope-from ) id 1PNUSR-0004bh-NH; Tue, 30 Nov 2010 10:57:39 -0700 Received: from [208.187.158.94] (helo=[172.16.1.35]) by in01.mta.xmission.com with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.69) (envelope-from ) id 1PNUSR-0002Pu-00; Tue, 30 Nov 2010 10:57:39 -0700 Message-ID: <4CF53B0B.8060906@gmail.com> Date: Tue, 30 Nov 2010 10:57:31 -0700 From: Rob Sargent User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.15) Gecko/20101026 SUSE/3.0.10 Lightning/1.0b1 Thunderbird/3.0.10 MIME-Version: 1.0 To: pgsql-sql@postgresql.org References: <4CF53797.4040806@gmail.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-XM-SPF: eid=; ; ; mid=; ; ; hst=in01.mta.xmission.com; ; ; ip=208.187.158.94; ; ; frm=robjsargent@gmail.com; ; ; spf=neutral X-XM-AID: U2FsdGVkX18xhiMDCTvECrUMSqcrFjZ1Y4BxyWvTuxA= X-SA-Exim-Connect-IP: 208.187.158.94 X-SA-Exim-Mail-From: robjsargent@gmail.com X-Spam-DCC: XMission; sa05 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ;pgsql-sql@postgresql.org X-Spam-Relay-Country: Subject: Re: indexing longish string X-SA-Exim-Version: 4.2.1 (built Fri, 06 Aug 2010 16:31:04 -0600) X-SA-Exim-Scanned: Yes (on in01.mta.xmission.com) X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-2.6 tagged_above=-5 required=5 tests=BAYES_00=-1.9, RCVD_IN_DNSWL_LOW=-0.7 X-Spam-Level: X-Archive-Number: 201011/93 X-Sequence-Number: 34831 If the performance against an index doesn't cut it, we would be forced to choose just such an implementation, but if pg can do it straight up that would be less work for us. A good thing, to be sure. On 11/30/2010 10:50 AM, jose wrote: > Why don't you use some type of hash like md5 for indexing ? > > 2010/11/30 Rob Sargent : >> Were we to create a table which included a text field for a small block >> of xml (100-1000 chars worth), would an index on that field be useful >> against exact match queries? >> >> We're wondering if a criterion such as "where 'a string expected to be >> of size range 100 to 500' = tabelWithStrings.stringSearched" would make >> good use of an index on "stringSearched" column. >> >> The key is that there will only be exact match queries. >> >> Thanks for your thoughts. >> >> >> >> -- >> Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org) >> To make changes to your subscription: >> http://www.postgresql.org/mailpref/pgsql-sql >> >