From: Tom Lane <tgl@sss.pgh.pa.us>
To: Ron Johnson <ronljohnsonjr@gmail.com>
cc: "pgsql-generallists.postgresql.org" <pgsql-general@lists.postgresql.org>
Subject: Re: Allowed to return possibly TOASTed datums?
In-reply-to: <CANzqJaCngKMjcxtzHPggWV3mQU8U2E0zqxDtkznSpQbmPgTCgg@mail.gmail.com>
References: <20241214142827.fa730433d412246d424436e3@magnetkern.de> <1387150.1734195709@sss.pgh.pa.us> <CANzqJaCngKMjcxtzHPggWV3mQU8U2E0zqxDtkznSpQbmPgTCgg@mail.gmail.com>
Comments: In-reply-to Ron Johnson <ronljohnsonjr@gmail.com>
	message dated "Sat, 14 Dec 2024 13:13:55 -0500"
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Date: Sat, 14 Dec 2024 16:37:30 -0500
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Ron Johnson <ronljohnsonjr@gmail.com> writes:
> Since the purpose of TOAST is just (I think) to store "large field values"
> on disk by dividing into multiple chunks, what would be the purpose of
> returning the TOASTed value to Jan's function?

Probably not much.  There are scenarios where not detoasting
saves work overall, because the object never has to get detoasted;
but I think that's rare.  It'd probably look like

	UPDATE t SET c = no_op_function(c) WHERE ...

which is something few people would write.

			regards, tom lane