Re: pgsql: Ignore PlaceHolderVars when looking up statistics - Mailing list pgsql-hackers

From Tom Lane
Subject Re: pgsql: Ignore PlaceHolderVars when looking up statistics
Date
Msg-id 271338.1767388841@sss.pgh.pa.us
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In response to Re: pgsql: Ignore PlaceHolderVars when looking up statistics  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: pgsql: Ignore PlaceHolderVars when looking up statistics
Re: pgsql: Ignore PlaceHolderVars when looking up statistics
List pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes:
> On Sun, Dec 28, 2025 at 9:45 PM Richard Guo <rguo@postgresql.org> wrote:
>> Back-patch to v18.  Although this issue exists before that, changes in
>> this version made it common enough to notice.  Given the lack of field
>> reports for older versions, I am not back-patching further.

> Generally we don't back-patch fixes that could change plans, because
> it tends to produce user complaints. It's maybe more justifiable in
> this case because v18 is quite new and you didn't back-patch to older
> releases, but are we sure that it's warranted even there?

It's a regression if we don't.  See nearby complaint at

https://www.postgresql.org/message-id/flat/b75866aa-bb54-456b-8f88-6b5bc52064ca%40app.fastmail.com

That case was correctly handled in v17 and before.

            regards, tom lane



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