From: Mladen Gogala <mgogala@vmsinfo.com>
To: Neil Whelchel <neil.whelchel@gmail.com>
Cc: pgsql-performance@postgresql.org <pgsql-performance@postgresql.org>
Subject: Re: Slow count(*) again...
Date: Mon, 11 Oct 2010 16:58:37 -0400
Message-ID: <4CB37A7D.90502@vmsinfo.com> (raw)
In-Reply-To: <201010111254.58479.neil.whelchel@gmail.com>
References: <201010091626.18636.neil.whelchel@gmail.com>
<AANLkTimayTM__hHu9RoiLaNhzfpNY6Vo5y4OkbX_sV=o@mail.gmail.com>
<4CB34D69.6060108@emolecules.com>
<201010111254.58479.neil.whelchel@gmail.com>
Neil Whelchel wrote:
>
>
> That is why I suggested an estimate(*) that works like (a faster) count(*)
> except that it may be off a bit. I think that is what he was talking about
> when he wrote this.
>
>
The main problem with "select count(*)" is that it gets seriously
mis-used. Using "select count(*)" to establish existence is bad for
performance and for code readability.
--
Mladen Gogala
Sr. Oracle DBA
1500 Broadway
New York, NY 10036
(212) 329-5251
http://www.vmsinfo.com
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To: pgsql-performance@postgresql.org
Cc: mgogala@vmsinfo.com, neil.whelchel@gmail.com
Subject: Re: Slow count(*) again...
In-Reply-To: <4CB37A7D.90502@vmsinfo.com>
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