From: Richard Huxton <dev@archonet.com>
To: Joel Fradkin <jfradkin@wazagua.com>
Cc: gsstark@mit.edu
Cc: pgsql-sql@postgresql.org
Subject: Re: same question little different test MSSQL vrs Postgres
Date: Wed, 26 Jan 2005 13:58:58 +0000
Message-ID: <41F7A222.3040009@archonet.com> (raw)
In-Reply-To: <000401c503aa$f8ee5620$797ba8c0@jfradkin>
References: <000401c503aa$f8ee5620$797ba8c0@jfradkin>
Joel Fradkin wrote:
> QUERY PLAN
> "Seq Scan on tblcase (cost=0.00..30066.21 rows=37401 width=996) (actual
> time=0.344..962.260 rows=22636 loops=1)"
> " Filter: ((clientnum)::text = 'SAKS'::text)"
> "Total runtime: 1034.434 ms"
That's only 1 second - to return 22,636 rows. Not 27 seconds, as in the
original post. You'll never persuade PG to use the index when some 75%
of your rows match the filter - it just doesn't make sense.
--
Richard Huxton
Archonet Ltd
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To: pgsql-sql@postgresql.org
Cc: dev@archonet.com, jfradkin@wazagua.com, gsstark@mit.edu
Subject: Re: same question little different test MSSQL vrs Postgres
In-Reply-To: <41F7A222.3040009@archonet.com>
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