From: Joe Conway <mail@joeconway.com>
To: jasiek <jasiek@klaster.net>
Cc: ow <oneway_111@yahoo.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: Seq Scans when index expected to be used
Date: Sat, 29 Nov 2003 09:26:43 -0800
Message-ID: <3FC8D6D3.2030504@joeconway.com> (raw)
In-Reply-To: <20031129170913.M37199@klaster.net>
References: <20031129164924.51035.qmail@web21401.mail.yahoo.com>
<20031129170913.M37199@klaster.net>
jasiek wrote:
> On Sat, 29 Nov 2003 08:49:24 -0800 (PST), ow wrote
>
>>explain select b, c, a
>>from test
>>group by b, c, a
>>having count(*) > 1
Why would you expect this to use an index scan when it needs to read the
entire table? If you read the whole table (or even a significant
fraction of it), a seq scan is faster.
Joe
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To: pgsql-sql@postgresql.org
Cc: mail@joeconway.com, jasiek@klaster.net, oneway_111@yahoo.com
Subject: Re: Seq Scans when index expected to be used
In-Reply-To: <3FC8D6D3.2030504@joeconway.com>
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