From: Joe Conway <mail@joeconway.com>
To: ow <oneway_111@yahoo.com>
Cc: jasiek <jasiek@klaster.net>
Cc: pgsql-sql@postgresql.org
Subject: Re: Seq Scans when index expected to be used
Date: Sat, 29 Nov 2003 10:25:58 -0800
Message-ID: <3FC8E4B6.8030901@joeconway.com> (raw)
In-Reply-To: <20031129180159.91794.qmail@web21404.mail.yahoo.com>
References: <20031129180159.91794.qmail@web21404.mail.yahoo.com>
ow wrote:
> My impression was that the index "I_bca" covers the query, hence there should
> not be a need to go to the table itself. Why would it?
Postgres always has to go to the table. The ability to read data
directly from indexes (ala other RDBMSs) has been discussed, but not
implemented. IIRC it's a hard problem due to the way Postgres does MVCC.
Check the archives.
> explain analyze vs explain. Normally, would've used "explain analyze" but in
> this case it's taking way too long so I used "explain".
I can understand that, but most people will ask for explain analyze
anyway ;-)
Joe
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To: pgsql-sql@postgresql.org
Cc: mail@joeconway.com, oneway_111@yahoo.com, jasiek@klaster.net
Subject: Re: Seq Scans when index expected to be used
In-Reply-To: <3FC8E4B6.8030901@joeconway.com>
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