From: Tom Lane <tgl@sss.pgh.pa.us>
To: Ryan Holmes <ryan@hyperstep.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: IN operator causes sequential scan (vs. multiple OR expressions)
Date: Sat, 27 Jan 2007 18:53:06 -0500
Message-ID: <24016.1169941986@sss.pgh.pa.us> (raw)
In-Reply-To: <AE23623B-65E0-4CC8-8F7E-3920E4B42FDC@hyperstep.com>
References: <AE23623B-65E0-4CC8-8F7E-3920E4B42FDC@hyperstep.com>
Ryan Holmes <ryan@hyperstep.com> writes:
> I have a relatively simple query where the planner chooses a
> sequential scan when using the IN operator but chooses an index scan
> when using logically equivalent multiple OR expressions.
EXPLAIN ANALYZE for both, please?
If you set enable_seqscan = off, does that force an indexscan, and if so
what does EXPLAIN ANALYZE show in that case?
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, ryan@hyperstep.com
Subject: Re: IN operator causes sequential scan (vs. multiple OR expressions)
In-Reply-To: <24016.1169941986@sss.pgh.pa.us>
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