X-Original-To: pgsql-patches-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id E6A335E46CA for ; Fri, 13 Aug 2004 23:29:14 -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 57396-03 for ; Sat, 14 Aug 2004 02:29:14 +0000 (GMT) Received: from sss.pgh.pa.us (sss.pgh.pa.us [66.207.139.130]) by svr1.postgresql.org (Postfix) with ESMTP id 2DDE55E46C1 for ; Fri, 13 Aug 2004 23:29:11 -0300 (ADT) 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 i7E2T91P000447; Fri, 13 Aug 2004 22:29:09 -0400 (EDT) To: "Simon@2ndquadrant.com" Cc: "Bruce Momjian" , "Klaus Naumann" , markw@osdl.org, pgsql-patches@postgresql.org Subject: Re: [HACKERS] Point in Time Recovery In-reply-to: References: Comments: In-reply-to "Simon@2ndquadrant.com" message dated "Sat, 14 Aug 2004 01:50:22 +0100" Date: Fri, 13 Aug 2004 22:29:09 -0400 Message-ID: <446.1092450549@sss.pgh.pa.us> From: Tom Lane X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.0 tagged_above=0.0 required=5.0 tests=TO_ADDRESS_EQ_REAL X-Spam-Level: X-Archive-Number: 200408/284 X-Sequence-Number: 12573 "Simon@2ndquadrant.com" writes: > I would opt to make enabling/disabling archive_command require a postmaster > restart. That way there would be no capability to take advantage of the > incentive to turn it on/off. We're generally not in the habit of making GUC parameters more rigid than the implementation absolutely requires. > It would be my intention (in 8.1) to make those available via switches e.g. > NOT LOGGED options on CREATE INDEX and COPY, to allow users to take > advantage of the no logging optimization without turning off PITR system > wide. (Just as this is possible in Oracle and Teradata). Isn't this in direct conflict with your opinion above? And I cannot say that I think this one is a good idea. We do not have support for selective catalog xlogging; if you do something like this then you *will* have a broken database after recovery, because it will contain those indexes but with invalid contents. > I would also aim to make the first Insert Select into an empty table not > logged (optionally). This is an important optimization for Oracle, teradata > and DB2 (which uses NOT LOGGED INITIALLY). This is even worse: not only do you have a broken database, but you have no way to recover. (At least with an unlogged index you could fix it by REINDEX.) If you don't care about longevity of the table, then make it a temp table. The fact that Oracle does it does not automatically make it a good idea. regards, tom lane