From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
cc: Ilia Evdokimov <ilya.evdokimov@tantorlabs.com>,
        Andrei Lepikhov <lepihov@gmail.com>,
        pgsql-hackers@lists.postgresql.org
Subject: Re: explain analyze rows=%.0f
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
	message dated "Fri, 21 Feb 2025 20:16:20 -0500"
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Date: Fri, 21 Feb 2025 21:11:07 -0500
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Robert Haas <robertmhaas@gmail.com> writes:
> Yeah, I pushed an attempt at a band-aid fix. Hopefully that will make
> it clear whether there are other problems and how bad they are. It
> looks like the XversionUpgrade tests are not this commit's fault.

They are not, they're Jeff's problem.

I apologize if I ruffled your feathers.  But the buildfarm is a shared
resource and it doesn't do to leave it significantly broken over a
weekend, which I feared you might be about to do.  Committing stuff
at 4PM on a Friday is perhaps not the best plan if your intention
is to not work weekends.

On a positive note, at least some of the formerly-pink members
seem to be happy now.  So as you hoped, we can get more info about
whether there are less-frequent problems.

As for a permanent fix: maybe, instead of printing fractions when
actual nloops > 1, we should print fractions if *potential*
nloops > 1?  That is, anytime we're on the inside of a nestloop,
under a Gather, etc.  Seems like this'd not be too hard to track
while recursively descending the PlanState tree.

			regards, tom lane