Re: Why could GEQO produce plans with lower costs than the standard_join_search?

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Donald Dong <xdong(at)csumb(dot)edu>
Cc: PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org>
Subject: Re: Why could GEQO produce plans with lower costs than the standard_join_search?
Date: 2019-05-23 22:33:21
Message-ID: 1222.1558650801@sss.pgh.pa.us
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Donald Dong <xdong(at)csumb(dot)edu> writes:
> Perhaps the cheapest-total-cost should not be the best/only choice
> for fitness?

Well, really the GEQO code should be thrown out and rewritten from
the ground up ... but that hasn't quite gotten done yet.

regards, tom lane

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