Re: Order changes in PG16 since ICU introduction

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