Re: Built-in CTYPE provider

Jeff Davis wrote:

> > Jeremy also raised a problem with old versions of psql connecting to
> > a
> > new server: the \l and \dO won't work. Not sure exactly what to do
> > there, but I could work around it by adding a new field rather than
> > renaming (though that's not ideal).
>
> I did a bit of research for a precedent, and the closest I could find
> is that \dp was broken between 14 and 15 by commit 07eee5a0dc.

Another one is that version 12 broke \d in older psql by
removing pg_class.relhasoids.

ISTM that in general the behavior of old psql vs new server does
not weight much against choosing optimal catalog changes.

There's also that warning at start informing users about it:
WARNING: psql major version X, server major version Y.
Some psql features might not work.

Best regards,
--
Daniel Vérité
https://postgresql.verite.pro/
Twitter: @DanielVerite