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Message-ID: <533d93c5-f604-8e5f-4a48-975c08c53d59@enterprisedb.com>
Date: Fri, 21 Apr 2023 19:14:13 +0200
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Subject: Re: Order changes in PG16 since ICU introduction
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To: Sandro Santilli <strk@kbt.io>, Tom Lane <tgl@sss.pgh.pa.us>
Cc: Regina Obe <lr@pcorp.us>, pgsql-hackers@lists.postgresql.org,
 Jeff Davis <pgsql@j-davis.com>
References: <000b01d97465$c34bbd60$49e33820$@pcorp.us>
 <3353947.1682092131@sss.pgh.pa.us> <ZELDOktA75yYG4Z2@hst.kbt.io>
From: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
In-Reply-To: <ZELDOktA75yYG4Z2@hst.kbt.io>
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On 21.04.23 19:09, Sandro Santilli wrote:
> On Fri, Apr 21, 2023 at 11:48:51AM -0400, Tom Lane wrote:
>> "Regina Obe" <lr@pcorp.us> writes:
>>
>>> https://trac.osgeo.org/postgis/ticket/5375
>>
>> If they actually are using locale C, I would say this is a bug.
>> That should designate memcmp sorting and nothing else.
> 
> Sounds like a bug to me. This is happening with a PostgreSQL cluster
> created and served by a build of commit c04c6c5d6f :
> 
>    =# select version();
>    PostgreSQL 16devel on x86_64-pc-linux-gnu, compiled by gcc (Ubuntu 11.3.0-1ubuntu1~22.04) 11.3.0, 64-bit
>    =# show lc_collate;
>    C
>    =# select '+' < '-';
>    f

If the database is created with locale provider ICU, then lc_collate 
does not apply here, so the result might be correct (depending on what 
locale you have set).

>    =# select '+' < '-' collate "C";
>    t