From: Gregory Stark <stark@enterprisedb.com>
To: Andreas Haumer <andreas@xss.co.at>
Cc: Tom Lane <tgl@sss.pgh.pa.us>
Cc: pgsql-performance@postgresql.org
Subject: Re: Query performance problems with partitioned tables
Date: Mon, 30 Apr 2007 20:19:16 +0100
Message-ID: <87lkg9r7pn.fsf@oxford.xeocode.com> (raw)
In-Reply-To: <46362571.20301@xss.co.at>
References: <4635D678.3050205@xss.co.at>
<27303.1177945607@sss.pgh.pa.us>
<46362571.20301@xss.co.at>
Wait, rereading the original queries I seem to have misunderstood something.
The individual parts of the partitioned tables are being accessed in timestamp
order. So what's missing is some way for the optimizer to know that the
resulting append results will still be in order. If it knew that all the
constraints were mutually exclusive and covered ascending ranges then it could
avoid doing the extra sort. Hm...
--
Gregory Stark
EnterpriseDB http://www.enterprisedb.com
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To: pgsql-performance@postgresql.org
Cc: stark@enterprisedb.com, andreas@xss.co.at, tgl@sss.pgh.pa.us
Subject: Re: Query performance problems with partitioned tables
In-Reply-To: <87lkg9r7pn.fsf@oxford.xeocode.com>
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