Re: pgsql_fdw in contrib

Hi Hanada-san,

> It would be possible to add some more features, such as ORDER BY
> push-down with index information support, without changing existing
> APIs, but at first add relatively simple pgsql_fdw and enhance it seems
> better.  In addition, once pgsql_fdw has been merged, it would help
> implementing proof-of-concept of SQL/MED-related features.

I agree with on this point.  However, I think it is preferable that pgsql_fdw
should support, from the start, the push down of PARAM_EXEC params, and thus the
parameter-change-driven remote-rescanning functionality for that.  I think that
such a functionality is necessary for pgsql_fdw to efficiently process SubLinks
on remote tables, and to realize parameterized scans in future, which I think
will be proof-of-concept code to demonstrate how to enhance FDWs to developers,
as discussed in the earlier thread of IMAP FDW...

Thanks,

Best regards,
Etsuro Fujita