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Date: Tue, 27 Aug 2024 16:00:13 +1000
From: Justin Clift <justin@postgresql.org>
To: David Rowley <dgrowleyml@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, nikhil raj <nikhilraj474@gmail.com>,
 "pgsql-generallists.postgresql.org" <pgsql-general@lists.postgresql.org>,
 NIKITA PATEL <patelnikita1411@gmail.com>, Patel Khushbu
 <patelkhushbu2067@gmail.com>
Subject: Re: Significant Execution Time Difference Between PG13.14 and PG16.4
 for Query on information_schema Tables.
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On 2024-08-27 11:50, David Rowley wrote:
> On Tue, 27 Aug 2024 at 13:40, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Yeah, it looks like that condition on "table_name" is not getting
>> pushed down to the scan level anymore.  I'm not sure why not,
>> but will look closer tomorrow.
> 
> I was looking for the offending commit as at first I thought it might
> be related to Memoize. It does not seem to be.

As a general thought, seeing that this might be an actual problem
should some kind of automated testing be added that checks for
performance regressions like this?

Regards and best wishes,

Justin Clift