Re: Unfortunate pushing down of expressions below sort
Tom Lane <tgl@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Andres Freund <andres@anarazel.de>
Cc: pgsql-hackers@postgresql.org, David Rowley <dgrowleyml@gmail.com>
Date: 2026-02-06T01:02:31Z
Lists: pgsql-hackers
I wrote: > Yeah. That's a hangover from an ancient decision that sort/limit > would always be applied at the top of the plan tree. I'm too > lazy to check the details right now, but I think we already relaxed > that in some cases (or maybe it was about evaluating stuff > before/after GROUP BY?). Ah, right: see make_sort_input_target() and its very extensive comment in planner.c. I wonder why that didn't trigger in your example. regards, tom lane