Message-ID: <2e7bdb5d-68ba-4c65-9931-a865ab6fc3d2@gmail.com>
Date: Sat, 4 Apr 2026 23:02:37 +0200
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Subject: Re: pg_plan_advice
To: Robert Haas <robertmhaas@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Alexander Lakhin <exclusion@gmail.com>,
 Lukas Fittl <lukas@fittl.com>,
 PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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From: Andrei Lepikhov <lepihov@gmail.com>
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On 4/4/26 20:42, Robert Haas wrote:
> On Sat, Apr 4, 2026 at 5:34 AM Andrei Lepikhov <lepihov@gmail.com> wrote:
> By the way, I'm really glad you hit that error. That particular error
> check is there precisely to find plans that pg_plan_advice isn't able
> to understand, and it sounds like it is doing its job as intended.
> Having problems isn't great, but knowing that you have problems is a
> lot better than still having them but not knowing about it.
That’s exactly what concerns me. I see it as a potential design flaw if 
the extension has to make assumptions about possible plan configurations.
I’m not sure how it works in detail, of course. However, when I designed 
Postgres replanning in the past, and made similar core changes to what 
you’ve done for pg_plan_advice, this kind of problem couldn’t have 
happened. So, I think it’s worth questioning the current approach and 
looking for other options.

-- 
regards, Andrei Lepikhov,
pgEdge