shigeo Hirose <shigeo.hirose@toshiba.co.jp> writes:
> How can I pushdown of functions used in targetlist with FDW ?
There is, AFAIK, no provision for that. There's not a lot of
reason to consider adding it either, because there's no reason
to suppose that the remote node can run such a function any
faster than the local node. So the difficulty and risk of
determining/assuming that f(x) on the local node is the same
as f(x) on the remote node doesn't seem like it'd be repaid.
You can force matters by making a foreign table that points to a view
on the remote side, where the view includes the function call as an
output column. It wouldn't be perfectly transparent of course; you'd
have to modify the local query to refer to that column rather than
calling the function explicitly.
regards, tom lane