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From: Jake Magner <jakemagner90@gmail.com>
To: pgsql-performance@postgresql.org
Subject: Re: Merge Join chooses very slow index scan
Date: Thu, 19 Mar 2015 00:04:10 -0700 (MST)
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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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