From: Tom Lane <tgl@sss.pgh.pa.us>
To: Arctic Toucan <arctic_toucan@hotmail.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: OOM Errors as a result of table inheritance and a bad plan(?)
Date: Fri, 28 Sep 2007 16:56:49 -0400
Message-ID: <19037.1191013009@sss.pgh.pa.us> (raw)
In-Reply-To: <BAY126-W604E273FFED65685953D679CB20@phx.gbl>
References: <BAY126-W604E273FFED65685953D679CB20@phx.gbl>
Arctic Toucan <arctic_toucan@hotmail.com> writes:
> -- Is there something magical about the hash aggregate estimate of 200 rows?
Yeah, it's the default :-(
> Is this a bug, or some subtlety of the Postgres query planner?
It's an, um, known deficiency --- the planner hasn't got any idea how to
construct aggregated statistics for an inheritance tree.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, arctic_toucan@hotmail.com
Subject: Re: OOM Errors as a result of table inheritance and a bad plan(?)
In-Reply-To: <19037.1191013009@sss.pgh.pa.us>
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