From: Peter Eisentraut <peter@eisentraut.org>
To: Alvaro Herrera <alvherre@alvh.no-ip.org>
To: David Rowley <dgrowleyml@gmail.com>
Cc: Erik Wienhold <ewie@ewie.name>
Cc: pgsql-docs@lists.postgresql.org
Subject: Re: nchar is undocumented
Date: Mon, 6 May 2024 11:34:18 +0200
Message-ID: <0924daa4-53e8-40ee-b8a7-73307a8ea34a@eisentraut.org> (raw)
In-Reply-To: <202405060853.t3thj4gr4cpb@alvherre.pgsql>
References: <202405060853.t3thj4gr4cpb@alvherre.pgsql>
On 06.05.24 10:53, Alvaro Herrera wrote:
> On 2024-May-05, David Rowley wrote:
>
>> On Sun, 5 May 2024 at 12:41, Erik Wienhold <ewie@ewie.name> wrote:
>>> So, I think we should either remove that one nchar instance (because it
>>> doesn't add any real value) or document it properly. The attached patch
>>> does the latter.
>>
>> It seems easier to do the former, that way we don't need to reconsider
>> Peter's concerns about not having enough confidence that it matches
>> the standard.
>>
>> I've included Alvaro and Peter to see what they think.
>
> Yeah, I too am inclined to remove it. This text was initially written
> by Mantrova, Bartunov and Glukhov and posted in [1] without further
> explanation, from where it was copied by Glukhov into [2]; the one I
> committed is a direct derivate from that. There was no discussion about
> nchar specifically that I can see, and at least I simply failed to
> realize that nchar was not something that we talk about.
>
> I'll remove it from the list, and backpatch to 16.
Yeah, makes sense to at least undocument it consistently.
> If you, Erik, want to spend some time thinking through the standard
> definition of NCHAR and whether we conform, perhaps we can document it
> more fully.
I think the idea of NCHAR and its variants is that you could sort of
have two character sets pre-selected: One is the character set set by
the client (maybe historically ASCII) and the other is one you designate
as the "national" one. Since in PostgreSQL, a given session always has
one character set active, this is trivially true, so I think we can
leave it like that.
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-docs@postgresql.org
Cc: peter@eisentraut.org, alvherre@alvh.no-ip.org, dgrowleyml@gmail.com, ewie@ewie.name, pgsql-docs@lists.postgresql.org
Subject: Re: nchar is undocumented
In-Reply-To: <0924daa4-53e8-40ee-b8a7-73307a8ea34a@eisentraut.org>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox