Message-ID: <f61e4d50a2469585ec4af8ce4ab95331a858a8b0.camel@j-davis.com>
Subject: Re: Order changes in PG16 since ICU introduction
From: Jeff Davis <pgsql@j-davis.com>
To: Peter Eisentraut <peter.eisentraut@enterprisedb.com>, "Jonathan S. Katz"
	 <jkatz@postgresql.org>, Robert Haas <robertmhaas@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Regina Obe <lr@pcorp.us>, Sandro Santilli
	 <strk@kbt.io>, pgsql-hackers@lists.postgresql.org
Date: Thu, 25 May 2023 17:23:53 -0700
In-Reply-To: <275c47ea-e7f3-e654-c99a-63bc116997d7@enterprisedb.com>
References: <000b01d97465$c34bbd60$49e33820$@pcorp.us>
	 <3353947.1682092131@sss.pgh.pa.us> <ZELDOktA75yYG4Z2@hst.kbt.io>
	 <533d93c5-f604-8e5f-4a48-975c08c53d59@enterprisedb.com>
	 <3365333.1682098091@sss.pgh.pa.us>
	 <002d01d97477$f0395640$d0ac02c0$@pcorp.us>
	 <3367226.1682099185@sss.pgh.pa.us>
	 <003b01d9747a$910471c0$b30d5540$@pcorp.us>
	 <3368986.1682099982@sss.pgh.pa.us>
	 <000001d9747d$066b7560$13426020$@pcorp.us>
	 <3372735.1682101425@sss.pgh.pa.us>
	 <f83f089ee1e9acd5dbbbf3353294d24e1f196e95.camel@j-davis.com>
	 <CA+TgmobxgvonJT8vO_v0k9_rgDmn0CKvTe48Z=w95rrBqC95KA@mail.gmail.com>
	 <7ee07b7d5aa4fb0b47e5657640568fdd25ba168f.camel@j-davis.com>
	 <CA+TgmoaPGx+R6mOcYQwDfqGoZxd=SncDCDt9mYjz5AD5tFd8sw@mail.gmail.com>
	 <2ffe8ffb9291b9390b9ed6c1e34b4fae8e8ce324.camel@j-davis.com>
	 <25787ec7-4c04-9a8a-d241-4dc9be0b1ba3@postgresql.org>
	 <605324592391599a7ecd522087edbd00720793b7.camel@j-davis.com>
	 <f353900f4c5777b02e9c7ef85326f1954ffeccea.camel@j-davis.com>
	 <275c47ea-e7f3-e654-c99a-63bc116997d7@enterprisedb.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
User-Agent: Evolution 3.44.4-0ubuntu1 
MIME-Version: 1.0
Archived-At: <https://www.postgresql.org/message-id/f61e4d50a2469585ec4af8ce4ab95331a858a8b0.camel%40j-davis.com>
Precedence: bulk

On Mon, 2023-05-22 at 14:34 +0200, Peter Eisentraut wrote:
> Please put blank lines between
>=20
> </sect3>
> <sect3 ...>
>=20
> etc., matching existing style.
>=20
> We usually don't capitalize the collation parameters like
>=20
> CREATE COLLATION mycollation1 (PROVIDER =3D icu, LOCALE =3D 'ja-JP);
>=20
> elsewhere in the documentation.
>=20
> Table 24.2. ICU Collation Settings should probably be sorted by key,
> or=20
> at least by something.
>=20
> All tables should referenced in the text, like "Table x.y shows this
> and=20
> that."=C2=A0 (Note that a table could float to a different page in some=
=20
> output formats, so just putting it into a section without some=20
> introductory text isn't sound.)

Thank you, done.

> Table 24.1. ICU Collation Levels shows punctuation as level 4, which
> is=20
> only true in shifted mode, which isn't the default.=C2=A0 The whole
> business=20
> of treating variable collation elements is getting a bit lost in this
> description.=C2=A0 The kv option is described as "Classes of characters=
=20
> ignored during comparison at level 3.", which is effectively true but
> not the whole picture.

I organized the documentation around practical examples and available
options, and less around the conceptual model. I think that's a good
start, but you're right that it over-simplifies in a few areas.

Discussing the model would work better along with an explanation of ICU
rules, where you can make better use of those concepts. I feel like
there are some interesting things that can be done with rules, but I
haven't had a chance to really dig in yet.

Regards,
	Jeff Davis