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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Ayush Tiwari <ayushtiwari.slg01@gmail.com>
cc: 2320415112@qq.com, pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #19710: Incorrect DELETE result after LEFT JOIN optimization
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Comments: In-reply-to Ayush Tiwari <ayushtiwari.slg01@gmail.com>
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Ayush Tiwari <ayushtiwari.slg01@gmail.com> writes:
> On Mon, 21 Sept 2026 at 12:05, PG Bug reporting form <noreply@postgresql=
.org>
> wrote:
>> On PostgreSQL 17.10, a `DELETE` statement containing an `EXISTS` subque=
ry
>> with two `LEFT JOIN`s deletes a row even though the subquery predicate =
is
>> false.

> AFAICS this has been fixed[1] and will be part of next minor versions.

Yeah, this example is pretty nearly a duplicate of bug #19560 [1],
which prompted that rewrite.

			regards, tom lane

[1] https://www.postgresql.org/message-id/19560-54cd7ede78d5e355%40postgre=
sql.org