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From: Robert Haas <robertmhaas@gmail.com>
Date: Fri, 28 Jan 2022 09:07:32 -0500
Message-ID: <CA+TgmoaGDw2baysiK+qqL+c3roa-9cPSvJ_Kwdgx7RoPQR0TaA@mail.gmail.com>
Subject: Re: Parameter for planner estimate of recursive queries
To: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
Cc: Simon Riggs <simon.riggs@enterprisedb.com>, 
	PostgreSQL Hackers <pgsql-hackers@postgresql.org>
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On Tue, Jan 25, 2022 at 4:44 AM Peter Eisentraut
<peter.eisentraut@enterprisedb.com> wrote:
> On the one hand, this smells like a planner hint.  But on the other
> hand, it doesn't look like we will come up with proper graph-aware
> selectivity estimation system any time soon, so just having all graph
> OLTP queries suck until then because the planner hint is hardcoded
> doesn't seem like a better solution.  So I think this setting can be ok.

I agree. It's a bit lame, but seems pretty harmless, and I can't see
us realistically doing a lot better with any reasonable amount of
work.

-- 
Robert Haas
EDB: http://www.enterprisedb.com