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Re: Select count(*), the sequel - Mailing list pgsql-performance

From Mladen Gogala
Subject Re: Select count(*), the sequel
Date
Msg-id 4CBC3275.9020000@vmsinfo.com
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In response to Re: Select count(*), the sequel  (Vitalii Tymchyshyn <tivv00@gmail.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
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New York, NY 10036
(212) 329-5251
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