Re: Strange behaviour of SELECT ... IN

From: Jorge Sarmiento <jsarmiento(at)ccom(dot)org>
To: Martijn van Oosterhout <kleptog(at)svana(dot)org>
Cc: Stephan Szabo <sszabo(at)megazone23(dot)bigpanda(dot)com>, pgsql-general(at)postgresql(dot)org
Subject: Re: Strange behaviour of SELECT ... IN
Date: 2002-06-27 13:44:13
Message-ID: 200206270944.13485.jsarmiento@ccom.org
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> Wrong. The number of rows has everything to do with it. If the number of
> rows exceeds 50% of the table, a sequential scan is faster than an index
> scan.

Mi database has 3 000 000 registries, my queries are usually of 50 - 100
rows... so index is faster right?

> You can use enable_seq_scan=off to force it. Let us know if the index scan
> is actually significantly faster.

I have inserted that line in postgresql.conf, and received an error.
where should it be put?

> Oh, you did use VACUUM ANALYZE right?

yep...

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