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From: David Rowley <dgrowleyml@gmail.com>
Date: Thu, 18 Sep 2025 23:35:34 +1200
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Subject: Re: Why isn't PG using an index-only scan?
To: Andrei Lepikhov <lepihov@gmail.com>
Cc: Jean-Christophe BOGGIO <postgresql@thefreecat.org>,
	"pgsql-performance@lists.postgresql.org"
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On Thu, 18 Sept 2025 at 19:55, Andrei Lepikhov <lepihov@gmail.com> wrote:
> Imagine if we had a hook within the ExecProcNode. In that scenario, we
> could create a trivial extension that would stop the query after, let's
> say, 10 minutes of execution and display the current state. This would
> give us more reliable data on estimation and the state of the plan tree.

I recall something along those lines existing once in the extension
world. Or maybe just from a previous employer. I don't recall many of
the details. Maybe something like a function you pass an SQL string
and if you cancelled the query it reported the EXPLAIN ANALYZE done so
far. I assume it must have done something like LOG it as it couldn't
have shown the EXPLAIN as query results on cancel.

David