From: Tom Lane <tgl@sss.pgh.pa.us>
To: Murthy Nunna <mnunna@fnal.gov>
cc: "pgsql-admin@postgresql.org" <pgsql-admin@postgresql.org>
Subject: Re: pg_dump -Are statistics saved?
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Comments: In-reply-to Murthy Nunna <mnunna@fnal.gov>
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Date: Mon, 27 Nov 2023 19:45:45 -0500
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Murthy Nunna <mnunna@fnal.gov> writes:
> The pg_dump (used verbose) log said "pg_dump: reading extended statistics".

> Does it mean it saved statistics and they can be restored with pg_restore?

What that means is that it will output clones of any CREATE STATISTICS
commands you may have issued.

> If not, is it necessary to run ANALYZE after pg_restore?

That has always been necessary after a dump/restore, and still is.
The pg_dump man page makes this clear enough, I should think:

    The dump file produced by pg_dump does not contain the statistics used
    by the optimizer to make query planning decisions. Therefore, it is
    wise to run ANALYZE after restoring from a dump file to ensure optimal
    performance; see Section 25.1.3 and Section 25.1.6 for more
    information.

			regards, tom lane