Joe Conway <mail@joeconway.com> writes:
> Also I have been told (not verified by me) that MySQL at least supports
> using its own built-in collation. If so, how can we ever know that
> whatever Postgres is using will match that?
Ugh. mysql_fdw probably ought to default to no-sort-pushdown.
> I wonder if we should have an attribute of a foreign server that
> indicates whether sort pushdown is enabled or not.
This is something that would have to be implemented individually
by each FDW for which it's relevant. We could set a good precedent,
and perhaps standardize the option name, by doing that in postgres_fdw.
regards, tom lane
