Re: pgsql: Allow insert and update tuple routing and COPY for foreign table

On Mon, 2019-04-22 at 16:24 -0400, Robert Haas wrote:
> On Mon, Apr 22, 2019 at 3:37 PM Laurenz Albe <laurenz(dot)albe(at)cybertec(dot)at> wrote:
> > Sure, it is not hard to modify a FDW to continue working with v11.
> >
> > My point is that this should not be necessary.
>
> I'm not sure whether this proposal is a good idea or a bad idea, but I
> think that it's inevitable that FDWs are going to need some updating
> for new releases as the API evolves. That has happened before and
> will continue to happen.

Absolutely.
I am just unhappy that this change caused unnecessary breakage.

If you developed a read-only FDW for 9.2, it didn't break with the
write support introduced in 9.3, because that used different API
functions. That's how it should be IMHO.

If you developed a FDW for 9.1, it got broken in 9.2, because the
API had to change to allow returning multiple paths.
That was unfortunate but necessary, so it is ok.

Nothing in this patch required an incompatible change.

Yours,
Laurenz Albe