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From: Tom Lane <tgl@sss.pgh.pa.us>
To: David Rowley <dgrowleyml@gmail.com>
Cc: Jean-Christophe Boggio <postgresql@thefreecat.org>
Cc: pgsql-performance@lists.postgresql.org
Subject: Re: I don't understand that EXPLAIN PLAN timings
Date: Thu, 25 Jan 2024 16:32:27 -0500
Message-ID: <456126.1706218347@sss.pgh.pa.us> (raw)
In-Reply-To: <CAApHDvqoP04PS3g6+Wc4LvMEcvbre+iRiVmyph1U2jVJtTJBng@mail.gmail.com>
References: <61e642df-5f48-4e4e-b4c3-58936f90ddaa@thefreecat.org>
	<7c265c1a-2b87-4dc6-8d83-8c7d98e11a2c@thefreecat.org>
	<CAApHDvqX2qTihLG2K4OqzeRneg3h+bwdgL000SjYHPFKiU7eAA@mail.gmail.com>
	<0f1acdd6-1d6a-44bc-80a1-fde4c55c5263@thefreecat.org>
	<CAApHDvqoP04PS3g6+Wc4LvMEcvbre+iRiVmyph1U2jVJtTJBng@mail.gmail.com>

David Rowley <dgrowleyml@gmail.com> writes:
> I do wonder now if it was a bad idea to make Memoize build the hash
> table on plan startup rather than delaying that until we fetch the
> first tuple. I see Hash Join only builds its table during executor
> run.

Ouch!  If it really does that, yes it's a bad idea.

			regards, tom lane





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