On Tue, 2024-07-23 at 16:07 -0400, Tom Lane wrote:
> Well, it depends on which libc collation you have in mind. I was
> thinking of a libc-supplied C.UTF-8 collation, which I would expect
> to behave the same as pg_c_utf8, modulo which Unicode version it's
> based on.
Daniel Vérité documented[1] cases where the libc C.UTF-8 locale changed
the *sort* behavior, thereby affecting primary keys.
Regards,
Jeff Davis
[1]
https://www.postgresql.org/message-id/8a3dc06f-9b9d-4ed7-9a12-2070d8b0165f%40manitou-mail.org