Date: Fri, 6 Oct 2023 13:25:44 -0500
From: Nico Williams <nico@cryptonector.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Isaac Morland <isaac.morland@gmail.com>, Jeff Davis <pgsql@j-davis.com>,
	Chapman Flack <chap@anastigmatix.net>, pgsql-hackers@postgresql.org
Subject: Re: Pre-proposal: unicode normalized text
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On Fri, Oct 06, 2023 at 02:17:32PM -0400, Robert Haas wrote:
> On Fri, Oct 6, 2023 at 1:38 PM Nico Williams <nico@cryptonector.com> wrote:
> > On Fri, Oct 06, 2023 at 01:33:06PM -0400, Robert Haas wrote:
> > > On Thu, Oct 5, 2023 at 3:15 PM Nico Williams <nico@cryptonector.com> wrote:
> > > > Text+encoding can be just like bytea with a one- or two-byte prefix
> > > > indicating what codeset+encoding it's in.  That'd be how to encode
> > > > such text values on the wire, though on disk the column's type should
> > > > indicate the codeset+encoding, so no need to add a prefix to the value.
> > >
> > > Well, that would be making the encoding a per-value property, rather
> > > than a per-column property like collation as I proposed. I can't see
> >
> > On-disk it would be just a property of the type, not part of the value.
> 
> I mean, that's not how it works.

Sure, because TEXT in PG doesn't have codeset+encoding as part of it --
it's whatever the database's encoding is.  Collation can and should be a
porperty of a column, since for Unicode it wouldn't be reasonable to
make that part of the type.  But codeset+encoding should really be a
property of the type if PG were to support more than one.  IMO.