| From: | Ron Johnson <ronljohnsonjr(at)gmail(dot)com> | 
|---|---|
| To: | pgsql-general <pgsql-general(at)postgresql(dot)org> | 
| Subject: | Re: Loading the latest N rows into the cache seems way too fast. | 
| Date: | 2025-02-17 23:03:18 | 
| Message-ID: | CANzqJaC=6pUTsveOdL=FS1vz_FGjMbZKuzJ27JxsPfNbYN2fUA@mail.gmail.com | 
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| Lists: | pgsql-general | 
On Mon, Feb 17, 2025 at 4:51 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Ron Johnson <ronljohnsonjr(at)gmail(dot)com> writes:
> > On Mon, Feb 17, 2025 at 4:36 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)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.)
>
That's definitely taking a LOT longer...
-- 
Death to <Redacted>, and butter sauce.
Don't boil me, I'm still alive.
<Redacted> lobster!
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