From: Vitalii Tymchyshyn <tivv00@gmail.com>
To: pgsql-performance@postgresql.org
Subject: Re: Select count(*), the sequel
Date: Mon, 18 Oct 2010 10:58:39 +0300
Message-ID: <4CBBFE2F.3010801@gmail.com> (raw)
In-Reply-To: <4CB9D82F.9040505@gmail.com>
References: <4CB9D82F.9040505@gmail.com>
16.10.10 19:51, Mladen Gogala написав(ла):
> There was some doubt as for the speed of doing the select count(*) in
> PostgreSQL and Oracle.
> To that end, I copied the most part of the Oracle table I used before
> to Postgres. Although the copy
> wasn't complete, the resulting table is already significantly larger
> than the table it was copied from. The result still shows that Oracle
> is significantly faster:
Hello.
Did you vacuum postgresql DB before the count(*). I ask this because
(unless table was created & loaded in same transaction) on the first
scan, postgresql has to write hint bits to the whole table. Second scan
may be way faster.
Best regards, Vitalii Tymchyshyn
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Subject: Re: Select count(*), the sequel
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