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 1875152A4F for ; Fri, 18 Mar 2005 05:18:48 +0000 (GMT) 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 07911-04 for ; Fri, 18 Mar 2005 05:18:41 +0000 (GMT) Received: from sharp.noc24x7.com (unknown [69.56.128.138]) by svr1.postgresql.org (Postfix) with ESMTP id 23BF956481 for ; Fri, 18 Mar 2005 05:18:40 +0000 (GMT) Received: from [61.3.110.155] (helo=thenilgiris.web) by sharp.noc24x7.com with esmtp (Exim 4.44) id 1DC9sR-0005q1-3h; Fri, 18 Mar 2005 10:48:28 +0530 Received: by thenilgiris.web (Postfix, from userid 500) id 404AC5BF15; Fri, 18 Mar 2005 10:49:48 +0530 (IST) From: Kenneth Gonsalves To: Richard Huxton Subject: Re: Query performance problem Date: Fri, 18 Mar 2005 10:49:47 +0530 User-Agent: KMail/1.6.1 Cc: weberp@paradise.net.nz, pgsql-sql@postgresql.org References: <200503172120.20676.weberp@paradise.net.nz> <200503171801.19412.lawgon@thenilgiris.com> <42398EB9.2050707@archonet.com> In-Reply-To: <42398EB9.2050707@archonet.com> MIME-Version: 1.0 Content-Disposition: inline Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <200503181049.47566.lawgon@thenilgiris.com> X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - sharp.noc24x7.com X-AntiAbuse: Original Domain - postgresql.org X-AntiAbuse: Originator/Caller UID/GID - [0 0] / [47 12] X-AntiAbuse: Sender Address Domain - thenilgiris.com X-Source: X-Source-Args: X-Source-Dir: X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.078 tagged_above=0 required=5 tests=AWL X-Spam-Level: X-Archive-Number: 200503/255 X-Sequence-Number: 20734 On Thursday 17 Mar 2005 7:35 pm, Richard Huxton wrote: > Not necessarily. NOT NULL here helps to ensure you can add values > together without the risk of a null result. There are plenty of > "amount" columns that should be not-null (total spent, total > ordered etc). that makes sense - but is it necessary to have a not null constraint=20 when there is a default value? =2D-=20 regards kg http://www.livejournal.com/users/lawgon tally ho! http://avsap.sourceforge.net =E0=B2=87=E0=B2=82=E0=B2=A1=E0=B3=8D=E0=B2=B2=E0=B2=BF=E0=B2=A8=E0=B2=95=E0= =B3=8D=E0=B2=B8 =E0=AE=B5=E0=AE=BE=E0=AE=B4=E0=AF=8D=E0=AE=95!