Re: Mixed Locales and Upgrading

Adrian Klaver <adrian(dot)klaver(at)aklaver(dot)com> writes:
> On 4/29/20 1:10 PM, Don Seiler wrote:
>> On Tue, Apr 7, 2020 at 11:41 AM Don Seiler <don(at)seiler(dot)us
>> <mailto:don(at)seiler(dot)us>> wrote:
>> Since I'm not changing the postgres or template0 databases (leaving
>> those as en_US/LATIN1), do I keep lc_collate/lc_ctype as en_US? It's
>> just the template1 and application database that I've set to en_US.UTF-8.

I believe that those settings only affect locale-dependent processing
in the postmaster and/or background processes, which there should be
little or none of anyway. Processes connected to specific databases will
adopt the settings defined for those databases.

>> I'm also struggling to see how lc_messages is an empty string. It is
>> commented out in postgresql.conf but suggests 'C' will be the default.

> Are you sure?:
> Sets the language in which messages are displayed. Acceptable
> values are system-dependent; see Section 23.1 for more information. If
> this variable is set to the empty string (which is the default) then the
> value is inherited from the execution environment of the server in a
> system-dependent way. ..."

The "system-dependent way" is "adopt whatever the LANG/LC_foo environment
variables say at server startup", at least on non-Windows machines.
I think that C is the fallback if none of those variables are set, though.

Short answer is you shouldn't need to mess with these.

regards, tom lane