Re: ICU for global collation

At Wed, 14 Sep 2022 17:19:34 +0300, Marina Polyakova <m(dot)polyakova(at)postgrespro(dot)ru> wrote in
> Hello!
>
> I was surprised that it is allowed to create clusters/databases where
> the default ICU collations do not actually work due to unsupported
> encodings:
>
> $ initdb --encoding SQL_ASCII --locale-provider icu --icu-locale en-US
> -D data &&
> pg_ctl -D data -l logfile start &&
> psql -c "SELECT 'a' < 'b'" template1
> ...
> waiting for server to start.... done
> server started
> ERROR: encoding "SQL_ASCII" not supported by ICU

Indeed. If I did the following, the direction of the patch looks fine
to me.

If I executed initdb as follows, I would be told to specify
--icu-locale option.

> $ initdb --encoding sql-ascii --locale-provider icu hoge
> ...
> initdb: error: ICU locale must be specified

However, when I reran the command, it complains about incompatible
encoding this time. I think it's more user-friendly to check for the
encoding compatibility before the check for missing --icu-locale
option.

regards.

--
Kyotaro Horiguchi
NTT Open Source Software Center