Re: Select count(*), the sequel

From: Mladen Gogala <mladen(dot)gogala(at)vmsinfo(dot)com>
To: pgsql-performance(at)postgresql(dot)org
Subject: Re: Select count(*), the sequel
Date: 2010-10-18 11:41:41
Message-ID: 4CBC3275.9020000@vmsinfo.com
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On 10/18/2010 3:58 AM, Vitalii Tymchyshyn wrote:
> 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

Vitalli, yes I did vacuum before the count.

--
Mladen Gogala
Sr. Oracle DBA
1500 Broadway
New York, NY 10036
(212) 329-5251
www.vmsinfo.com

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