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Re: Outer cost higher than the inner cost - Mailing list pgsql-performance

From Tom Lane
Subject Re: Outer cost higher than the inner cost
Date
Msg-id 1676226.1722004247@sss.pgh.pa.us
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In response to Outer cost higher than the inner cost  (Stanisław Skonieczny <stanislaw.skonieczny@gmail.com>)
List pgsql-performance
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=?UTF-8?Q?Stanis=C5=82aw_Skonieczny?= <stanislaw.skonieczny@gmail.com> writes:
> What bothers me is that the inner plan cost (7430940) is higher than the
> outer plan cost (1131699).

I think it is estimating (based on knowledge of the ranges of join keys
in the two relations) that that input subplan won't need to be run to
completion.  See initial_cost_mergejoin in costsize.c.

            regards, tom lane

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