X-Original-To: pgsql-sql-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id 629FE52AF7 for ; Fri, 8 Jul 2005 13:08:50 -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 91628-04 for ; Fri, 8 Jul 2005 16:08:49 +0000 (GMT) Received: from perseverance.encs.concordia.ca (perseverance-96.encs.concordia.ca [132.205.96.94]) by svr1.postgresql.org (Postfix) with ESMTP id 57BD752AD8 for ; Fri, 8 Jul 2005 13:08:43 -0300 (ADT) Received: from [132.205.44.35] (IDENT:emilu@curacao.cs.concordia.ca [132.205.44.35]) by perseverance.encs.concordia.ca (8.12.11/8.12.11) with ESMTP id j68G8fXL001065 for ; Fri, 8 Jul 2005 12:08:41 -0400 Message-ID: <42CEA509.3090507@cs.concordia.ca> Date: Fri, 08 Jul 2005 12:08:41 -0400 From: Ying Lu User-Agent: Mozilla Thunderbird 1.0.2 (X11/20050317) X-Accept-Language: en-us, en MIME-Version: 1.0 To: pgsql-sql@postgresql.org Subject: Index creation question for expression (col1 || '-' || col2) Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.43 on perseverance.encs.concordia.ca at 2005/07/08 12:08:41 EDT X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.013 tagged_above=0 required=5 tests=AWL X-Spam-Level: X-Archive-Number: 200507/82 X-Sequence-Number: 22060 Greetings, A question about creating index for the following expression. CREATE INDEX idx_t1 ON test (col1 || '-' || col2); May I know is it possible and how I may create index for the expression such as "col1 || '-' || col2" for a table please? Thanks a lot, Emi