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From: Tom Lane <tgl@sss.pgh.pa.us>
To: nikhil raj <nikhilraj474@gmail.com>
cc: "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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Comments: In-reply-to nikhil raj <nikhilraj474@gmail.com>
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nikhil raj <nikhilraj474@gmail.com> writes:
> I've encountered a noticeable difference in execution time and query
> execution plan row counts between PostgreSQL 13 and PostgreSQL 16 when
> running a query on information_schema tables. Surprisingly, PostgreSQL 16
> is performing slower than PostgreSQL 13.

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.

			regards, tom lane