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Date: Mon, 13 Aug 2007 09:07:03 -0500
From: "Kevin Grittner" <Kevin.Grittner@wicourts.gov>
To: "valgog" <valgog@gmail.com>,<runic <runic@gmx.de>,
	<pgsql-performance@postgresql.org>
Subject: Re: select count(*) performance
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>>> valgog <valgog@gmail.com> 08/13/07 6:38 AM >>>=20
On Aug 11, 5:54 pm, Detlef Rudolph <ru...@gmx.de> wrote:
>
> I've tried the VACUUM ANALYSE, that doesn't help
> much, but VACUUM FULL improves Performance down
> from about 40 secs to 8.
=20
Det,
=20
I don't think anyone meant to suggest that VACUUM ANALYZE would improve =
the
count speed on a table which had become bloated, but its routine use would
PREVENT a table from becoming bloated.  Once bloat occurs, you need more
agressive maintenance, like VACUUM FULL or CLUSTER.
=20
VACUUM FULL tends to cause index bloat, so you will probably see performanc=
e
issues in other queries at the moment.  You will probably need to REINDEX
the table or use CLUSTER to clean that up.
=20
-Kevin
=20