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From: Tom Lane <tgl@sss.pgh.pa.us>
To: marcos sicat <marcos.sicat@atlasifs.com>
cc: Pavel Stehule <pavel.stehule@gmail.com>,
        "pgsql-bugs@lists.postgresql.org" <pgsql-bugs@lists.postgresql.org>
Subject: Re: Postgres 17.4 is much slower than Postgres 15.12 using RECURSIVE
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Comments: In-reply-to marcos sicat <marcos.sicat@atlasifs.com>
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marcos sicat <marcos.sicat@atlasifs.com> writes:
> The function is the same between v15 and v17.  Is there a subtle differe=
nce in performance for nested subqueries in v17?

Your next step should be to compare the plans for the function's
query.  The auto_explain or pg_stat_statements extensions could
be used to check that in-situ, if manually EXPLAINing that query
doesn't yield insight.

			regards, tom lane