Message-ID: <1d178eb1bbd61da1bcfe4a11d6545e9cdcede1d1.camel@j-davis.com>
Subject: Re: Built-in CTYPE provider
From: Jeff Davis <pgsql@j-davis.com>
To: Noah Misch <noah@leadboat.com>
Cc: Peter Eisentraut <peter@eisentraut.org>, Daniel Verite
	 <daniel@manitou-mail.org>, Robert Haas <robertmhaas@gmail.com>, Jeremy
	Schneider <schneider@ardentperf.com>, pgsql-hackers@postgresql.org
Date: Fri, 05 Jul 2024 14:38:45 -0700
In-Reply-To: <20240704212641.c4.nmisch@google.com>
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On Thu, 2024-07-04 at 14:26 -0700, Noah Misch wrote:
> I think you're saying that if some Unicode update changes the results
> of a
> STABLE function but does not change the result of any IMMUTABLE
> function, we
> may as well import that update.=C2=A0 Is that about right?=C2=A0 If so, I
> agree.

If you are proposing that Unicode updates should not be performed if
they affect the results of any IMMUTABLE function, then that's a new
policy.

For instance, the results of NORMALIZE() changed from PG15 to PG16 due
to commit 1091b48cd7:

  SELECT NORMALIZE(U&'\+01E030',nfkc)::bytea;

  Version 15: \xf09e80b0

  Version 16: \xd0b0

I am neither endorsing nor opposing the new policy you propose at this
time, but deep in the sub-thread of one particular feature is not the
right place to discuss it.

Please start a new thread for the proposed PG18 policy change and CC
me. I happen to think that around the release of the next version of
Unicode (in a couple months) would be the most productive time to have
that discussion, but you can start the discussion now if you like.

Regards,
	Jeff Davis