From: Tom Lane <tgl@sss.pgh.pa.us>
To: "Jonathan S. Katz" <jkatz@postgresql.org>
cc: Michael Paquier <michael@paquier.xyz>,
 David Rowley <dgrowleyml@gmail.com>,
        exclusion@gmail.com, pgsql-bugs@lists.postgresql.org
Subject: Re: BUG #18240: Undefined behaviour in cash_mul_flt8() and friends
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Comments: In-reply-to "Jonathan S. Katz" <jkatz@postgresql.org>
	message dated "Sun, 24 Dec 2023 12:16:31 -0500"
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Date: Sun, 24 Dec 2023 13:21:15 -0500
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"Jonathan S. Katz" <jkatz@postgresql.org> writes:
> I'm of the strong opinion that we should get rid of money. I personally 
> haven't encountered it in the wild -- I'm sure it's there, but it seems 
> limited -- and most apps that seriously deal with money will either user 
> either "numeric" or an integer-based type.

Yeah, maybe we should just do it.  I was pleasantly surprised by how
little push-back we got from nuking the 32-bit datetime types a few
releases ago; perhaps this one would likewise not have much of a
constituency.

> I am sensitive to the upgrade piece, as we don't want someone relying on 
> that behavior to be indefinitely stuck. But perhaps part of the 
> deprecation plan is to just keep the casts around[1] for a few releases, 
> without exposing the type, and prevent new creations of the type?

I don't really see a way to do that, especially not if we don't want
to put a large amount of effort into it.  We can certainly make
pg_upgrade reject "money" columns, and tell people they need to
rewrite those before they upgrade not after.

			regards, tom lane