Re: BUG #18894: values of JLC_COLLATE and LC_CTYPE in the database have changed from Japanese_Japan.932 to ja-jp

On Mon, 2025-04-14 at 06:08 +0000, PG Bug reporting form wrote:
> PostgreSQL version: 17.4
> Operating system: windows server 2019 Datacenter
>
> In PostgreSQL 17.1, the values of JLC_COLLATE and LC_CTYPE in the database
> are Japanese_Japan.932. However, in PostgreSQL 17.4,
> they have changed to ja-JP. When upgrading from PostgreSQL 14.13 to
> PostgreSQL 17.4,
> the values of JLC_COLLATE and LC_CTYPE remain as Japanese_Japan.932.
>
> I would like to know if this change affects data sorting and other
> operations. If it does,
> what parameters should be specified during the upgrade to change
> Japanese_Japan.932 to ja-JP?

This is a duplicate of
https://www.postgresql.org/message-id/flat/CABv1Mx6uBG1OJX3%2BFHewqCoGtGuQqsLniB47WUrrt8sd1PDK1Q%40mail.gmail.com
and is not a PostgreSQL bug. Still, it is a problem.

We think that these are just two different names for the same thing.
But you need the names to be identical for pg_upgrade.

So remove the cluster and run "initdb" by hand, specifying the
old locale names just like they look on the old cluster.

Yours,
Laurenz Albe