From: Tom Lane <tgl@sss.pgh.pa.us>
To: Pavel Stehule <pavel.stehule@gmail.com>
cc: pgsql-hackers@lists.postgresql.org
Subject: Re: Modernizing our GUC infrastructure
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Comments: In-reply-to Pavel Stehule <pavel.stehule@gmail.com>
	message dated "Tue, 06 Sep 2022 06:32:21 +0200"
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Date: Tue, 06 Sep 2022 01:25:14 -0400
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Pavel Stehule <pavel.stehule@gmail.com> writes:
> The bad performance is not the main reason for implementing session
> variables (and in almost all cases the performance of GUC is not a problem,
> because it is not a bottleneck, and in some terrible cases, I can save the
> GUC to a variable). There are other differences:

Well, yeah, the schema-variables patch offers a bunch of other features.
What I'm not sure about is whether there's actually much field demand
for those.  I think if we fix guc.c's performance issues and add some
simple features on top of that, like the ability to declare bool, int,
float data types not just string for a user-defined GUC, we'd have
exactly what a lot of people want --- not least because it'd be
upwards-compatible with what they are already doing.

However, that's probably a debate to have on the other thread not here.
This patch doesn't foreclose pushing forward with the schema-variables
patch, if people want that.

			regards, tom lane