From: Tom Lane <tgl@sss.pgh.pa.us>
To: Richard Guo <guofenglinux@gmail.com>
cc: Vik Fearing <vik@postgresfriends.org>, Kamil Monicz <kamil@monicz.dev>,
        pgsql-bugs@lists.postgresql.org,
        Peter Eisentraut <peter@eisentraut.org>
Subject: Re: BUG #19106: Potential regression with CTE materialization
 planning in Postgres 18
In-reply-to: <3215004.1763142948@sss.pgh.pa.us>
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Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Fri, 14 Nov 2025 12:55:48 -0500"
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Date: Tue, 18 Nov 2025 12:59:34 -0500
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I wrote:
> The more I think about this, the more I like the other idea of just
> throwing an error rather than trying to fix up cases like bug #19055.
> I don't think we have much evidence that anyone is trying to do that
> in the real world (otherwise reports would have surfaced years ago).
> And this discussion is making it clear that fixing it up is harder
> than it sounds.

Hearing no further comments, I've pushed the v2 patch that does it
that way, restoring the previous behavior in cases that would not
have failed before #19055.

			regards, tom lane