X-Original-To: pgsql-performance-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.2]) by svr1.postgresql.org (Postfix) with ESMTP id 5786ED1CA90 for ; Fri, 6 Feb 2004 14:55:32 +0000 (GMT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (neptune.hub.org [200.46.204.2]) (amavisd-new, port 10024) with ESMTP id 30542-06 for ; Fri, 6 Feb 2004 10:55:34 -0400 (AST) Received: from sss.pgh.pa.us (unknown [192.204.191.242]) by svr1.postgresql.org (Postfix) with ESMTP id 1AB15D1C7F7 for ; Fri, 6 Feb 2004 10:55:30 -0400 (AST) Received: from sss2.sss.pgh.pa.us (tgl@localhost [127.0.0.1]) by sss.pgh.pa.us (8.12.11/8.12.11) with ESMTP id i16EtSel029561; Fri, 6 Feb 2004 09:55:28 -0500 (EST) To: Richard Huxton Cc: alvarezp@alvarezp.ods.org, pgsql-performance@postgresql.org Subject: Re: Seq scan on zero-parameters function In-reply-to: <200402060850.50818.dev@archonet.com> References: <4207.192.168.0.64.1076051944.squirrel@alvarezp.ods.org> <200402060850.50818.dev@archonet.com> Comments: In-reply-to Richard Huxton message dated "Fri, 06 Feb 2004 08:50:50 +0000" Date: Fri, 06 Feb 2004 09:55:28 -0500 Message-ID: <29560.1076079328@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: by amavisd-new at postgresql.org X-Archive-Number: 200402/90 X-Sequence-Number: 5614 Richard Huxton writes: > It's not entirely clear to me why this form is different from the other form > though. The code that checks for expressions containing unstable functions doesn't look inside sub-selects. Arguably this is a bug, but people were relying on that behavior way back before we had these nice STABLE/IMMUTABLE tags for functions. I'm hesitant to change it for fear of breaking people's apps. regards, tom lane