From: Josh Berkus <josh@agliodbs.com>
Organization: Aglio Database Solutions
To: pgsql-performance@postgresql.org
Subject: Re: Query is not using index when it should
Date: Sun, 12 Dec 2004 18:48:27 -0800
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Cc: tomas@nocrew.org (Tomas =?iso-8859-1?q?Sk=E4re?=)
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Tomas,

> I tried to subscribe to pgsql-performance, but there seems to be
> something wrong with the majordomo, so I'm sending to general too,
> where I'm already subscribed.

Well, I got your e-mail, so obviously you're subscribed to Performance.

> But when doing a search with objectid, class and field, it doesn't use
> the idx_cjm_object1 index.
> db=# explain analyze select * from cjm_object where objectid=4534 and
> class=12 and field='paroid'; QUERY PLAN

Try:

explain analyze select * from cjm_object where objectid=4534::BIGINT and
class=12 and field='paroid';

Sometimes the planner needs a little extra help on BIGINT fields.   This 
problem is fixed in 8.0.

-- 
Josh Berkus
Aglio Database Solutions
San Francisco