Re: Why does row estimation on nested loop make no sense to me

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Jeff Amiel <becauseimjeff(at)yahoo(dot)com>
Cc: "pgsql-general(at)postgresql(dot)org" <pgsql-general(at)postgresql(dot)org>
Subject: Re: Why does row estimation on nested loop make no sense to me
Date: 2013-05-17 16:35:22
Message-ID: 26056.1368808522@sss.pgh.pa.us
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Jeff Amiel <becauseimjeff(at)yahoo(dot)com> writes:
> How can the estimated number of rows for the nested loop node EXCEED the product of the 2 row estimates of the tables being joined?
> Not only does it exceed it - but it is orders of magnitude greater.

Can you provide a self-contained test case that does this?

regards, tom lane

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