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Re: When are index scans used over seq scans?

From: Richard van den Berg <richard(dot)vandenberg(at)trust-factory(dot)com>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: pgsql-perform <pgsql-performance(at)postgresql(dot)org>
Subject: Re: When are index scans used over seq scans?
Date: 2005-04-22 09:04:17
Message-ID: 4268BE11.6070200@trust-factory.com (view raw or flat)
Thread:
Lists: pgsql-performance
Tom Lane wrote:
> Are the tables in question particularly wide (many columns)?

Yes they are. They both have 20 columns. If I cut down the duration
table to just 1 column of timestamps, the planner uses the index.

Interesting, so I could store just the timestamps in another table (view
doesn't help) to speed up this query.

I am using the debian package. How can I tell if profiling is enabled?

Thanks a lot,

-- 
Richard van den Berg, CISSP
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