Re: [HACKERS] Slow count(*) again...

From: Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com>
To: Robert Haas <robertmhaas(at)gmail(dot)com>
Cc: david(at)lang(dot)hm, Vitalii Tymchyshyn <tivv00(at)gmail(dot)com>, Jon Nelson <jnelson+pgsql(at)jamponi(dot)net>, Mladen Gogala <mladen(dot)gogala(at)vmsinfo(dot)com>, Andrew Dunstan <andrew(at)dunslane(dot)net>, Bruce Momjian <bruce(at)momjian(dot)us>, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Craig Ringer <craig(at)postnewspapers(dot)com(dot)au>, "pgsql-performance(at)postgresql(dot)org" <pgsql-performance(at)postgresql(dot)org>
Subject: Re: [HACKERS] Slow count(*) again...
Date: 2011-02-04 03:13:22
Message-ID: AANLkTi=s7yBPnZEbO6GAk_tUeRH_bZL=fi3NsfKxPKFf@mail.gmail.com
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On Thu, Feb 3, 2011 at 7:05 PM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> If you want to randomly pick 10,000 rows out of all the rows that are
> going to be inserted in the table without knowing in advance how many
> there will be, how do you do that?

Maybe you could instead just have it use some % of the rows going by?
Just a guess.

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