Re: BUG #16583: merge join on tables with different DB collation behind postgres_fdw fails - Mailing list pgsql-hackers

From Tom Lane
Subject Re: BUG #16583: merge join on tables with different DB collation behind postgres_fdw fails
Date
Msg-id 2501728.1632578373@sss.pgh.pa.us
Whole thread Raw
In response to Re: BUG #16583: merge join on tables with different DB collation behind postgres_fdw fails  (Etsuro Fujita <etsuro.fujita@gmail.com>)
Responses Re: BUG #16583: merge join on tables with different DB collation behind postgres_fdw fails  (Etsuro Fujita <etsuro.fujita@gmail.com>)
Re: BUG #16583: merge join on tables with different DB collation behind postgres_fdw fails  (Jeremy Schneider <schnjere@amazon.com>)
List pgsql-hackers
Etsuro Fujita <etsuro.fujita@gmail.com> writes:
> On Sat, Sep 25, 2021 at 4:11 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Longer-term, it seems like we really have to be able to represent
>> the notion of a remote column that has an "unknown" collation (that
>> is, one that doesn't match any local collation, or at least is not
>> known to do so).

> +1

> In addition, a) we should detect whether local “default” matches
> remote “default”,

If we had a way to do that, most of the problem here wouldn't exist.
I don't believe we can do it reliably.  (Maybe we could put it on
the user to tell us, say via a foreign-server property?)

            regards, tom lane



pgsql-hackers by date:

Previous
From: Etsuro Fujita
Date:
Subject: Re: BUG #16583: merge join on tables with different DB collation behind postgres_fdw fails
Next
From: Mark Dilger
Date:
Subject: Re: Fixing WAL instability in various TAP tests