Received: from mta1.snet.net (mta1.snet.net [204.60.203.70]) by postgresql.org (8.11.3/8.11.4) with ESMTP id g1FGI4E19274 for ; Fri, 15 Feb 2002 11:18:04 -0500 (EST) (envelope-from wweng@kencast.com) Received: from pop.snet.net ([204.60.203.73]) by mta1.snet.net (8.12.1/8.12.1/SNET-smtp-1.1/D-1.1/O-1.1) with ESMTP id g1FGGg0G000569 for ; Fri, 15 Feb 2002 11:16:43 -0500 (EST) Received: from kencast.com (167.95.252.64.snet.net [64.252.95.167]) by pop.snet.net (8.12.1/8.12.1/SNET-pop-1.2/D-1.2/O-1.3) with ESMTP id g1FGI6B8004028 for ; Fri, 15 Feb 2002 11:18:06 -0500 (EST) Message-ID: <3C6D3684.9040101@kencast.com> Date: Fri, 15 Feb 2002 11:25:40 -0500 From: Wei Weng Reply-To: wweng@kencast.com User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.8) Gecko/20020205 X-Accept-Language: en-us MIME-Version: 1.0 To: pgsql-sql@postgresql.org Subject: create index on function - why? Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Archive-Number: 200202/176 X-Sequence-Number: 6602 I can understand the rationale behind creating index on tables, it speeds up the searching. But what is the rationale behind creating index on a function? how does it help with the database performance? Thank you. -- Wei Weng Network Software Engineer KenCast Inc.