From: Tom Lane <tgl@sss.pgh.pa.us>
To: Ron Johnson <ronljohnsonjr@gmail.com>
cc: pgsql-general <pgsql-general@postgresql.org>
Subject: Re: Loading the latest N rows into the cache seems way too fast.
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Comments: In-reply-to Ron Johnson <ronljohnsonjr@gmail.com>
	message dated "Mon, 17 Feb 2025 16:40:56 -0500"
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Date: Mon, 17 Feb 2025 16:51:10 -0500
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Ron Johnson <ronljohnsonjr@gmail.com> writes:
> On Mon, Feb 17, 2025 at 4:36 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> It's not pulling in the TOAST storage where the bytea column lives.
>> (pg_prewarm wouldn't have either, without special pushups.)

> Puzzling, since I ran "PERFORM *".  What if I explicitly mentioned the
> bytea column's name?

You'd have to do something that actually used the column's value,
perhaps "md5(byteacol)" or such.  (The obvious candidate would be
length(), but I think that is optimized to not fetch or decompress
the whole value.)

			regards, tom lane