Re: Merge Join chooses very slow index scan

From: Jake Magner <jakemagner90(at)gmail(dot)com>
To: pgsql-performance(at)postgresql(dot)org
Subject: Re: Merge Join chooses very slow index scan
Date: 2015-03-19 07:04:10
Message-ID: 1426748650278-5842527.post@n5.nabble.com
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random_page_cost = 4
seq_page_cost = 1

Regardless of the the choice to use the index scan and random access to the
rows, how come in the second query with the freq > -1 condition, it accesses
far fewer pages with the same index scan even though no rows are filtered
out?

Thanks

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