From: Tom Lane <tgl@sss.pgh.pa.us>
To: Justin Pryzby <pryzby@telsasoft.com>
cc: pgsql-performance@postgresql.org
Subject: Re: no MCV list of tiny table with unique columns
In-reply-to: <20161102185318.GA3987@telsasoft.com>
References: <20161102185318.GA3987@telsasoft.com>
Comments: In-reply-to Justin Pryzby <pryzby@telsasoft.com>
	message dated "Wed, 02 Nov 2016 13:53:18 -0500"
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Date: Wed, 02 Nov 2016 16:05:46 -0400
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Justin Pryzby <pryzby@telsasoft.com> writes:
> I believe the join is being (badly) underestimated, leading to a crappy plan
> involving multiple nested loop joins, which takes 2.5 hours instead of a
> handful of seconds; I believe that might be resolved by populating its MCV
> list..

With only two rows in the table, I'm not real sure why you'd need an MCV
list.  Could we see the actual problem query (and the other table
schemas), rather than diving into the code first?

			regards, tom lane


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