From: Tom Lane <tgl@sss.pgh.pa.us>
To: Amit Langote <amitlangote09@gmail.com>
cc: Alvaro Herrera <alvherre@alvh.no-ip.org>,
        Robert Haas <robertmhaas@gmail.com>,
        Jacob Champion <jchampion@timescale.com>,
        David Rowley <dgrowleyml@gmail.com>,
        PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: generic plans and "initial" pruning
In-reply-to: <CA+HiwqGFm_5aUqPnt=WCarkJ2ZU6F8kD8pFeGurHP+NZWS8KQw@mail.gmail.com>
References: <20221221101846.7zsi7lscnm5ediik@alvherre.pgsql> <1350682.1671635927@sss.pgh.pa.us> <4191508.1674157166@sss.pgh.pa.us> <CA+HiwqFhQ8tLMLQAWYRWiBQUrWSLM8qhVzJ4B5jWr=orUXfSyA@mail.gmail.com> <349124.1674185509@sss.pgh.pa.us> <CA+HiwqGFm_5aUqPnt=WCarkJ2ZU6F8kD8pFeGurHP+NZWS8KQw@mail.gmail.com>
Comments: In-reply-to Amit Langote <amitlangote09@gmail.com>
	message dated "Fri, 20 Jan 2023 12:52:07 +0900"
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Date: Thu, 19 Jan 2023 22:58:36 -0500
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Amit Langote <amitlangote09@gmail.com> writes:
> On Fri, Jan 20, 2023 at 12:31 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> It might be possible to incorporate this pointer into PlannedStmt
>> instead of passing it separately.

> Yeah, that would be less churn.  Though, I wonder if you still hold
> that PlannedStmt should not be scribbled upon outside the planner as
> you said upthread [1]?

Well, the whole point of that rule is that the executor can't modify
a plancache entry.  If the plancache itself sets a field in such an
entry, that doesn't seem problematic from here.

But there's other possibilities if that bothers you; QueryDesc
could hold the field, for example.  Also, I bet we'd want to copy
it into EState for the main initialization recursion.

			regards, tom lane