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From: David Rowley <dgrowleyml@gmail.com>
Date: Wed, 28 Aug 2024 11:57:53 +1200
Message-ID: <CAApHDvr2v7iwMUsCQKxUPSSzTGuBOx1_e0hyEA8VLy1or35JVA@mail.gmail.com>
Subject: Re: Significant Execution Time Difference Between PG13.14 and PG16.4
 for Query on information_schema Tables.
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Richard Guo <guofenglinux@gmail.com>, nikhil raj <nikhilraj474@gmail.com>, 
	pgsql-hackers@lists.postgresql.org
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On Wed, 28 Aug 2024 at 11:37, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Oh, scratch that, I see you mean this is an additional way to do it
> not the only way to do it.  But I'm confused why it works for
>         t1.two+1 AS c1
> but not
>         t1.two+t2.two AS c1
> Those ought to look pretty much the same for this purpose.

The bms_overlap(pull_varnos(rcon->root, newnode), rcon->relids) test
is false with t1.two+1.  Looks like there needs to be a Var from t2
for the bms_overlap to be true

David