Re: FDW: should GetFdwRoutine be called when drop table?

Andres Freund <andres@anarazel.de> writes:
> On 2016-02-19 14:18:19 -0500, Peter Eisentraut wrote:
>> On 2/19/16 12:21 PM, Feng Tian wrote:
>>> I have an fdw that each foreign table will acquire some persisted resource.

>> But foreign data wrappers are meant to be wrappers around data managed
>> elsewhere, not their own storage managers (although that is clearly
>> tempting), so there might well be other places where this breaks down.

> Sounds like even a BEGIN;DROP TABLE foo;ROLLBACK; will break this
> approach.

Yes, that's exactly the problem: you'd need some sort of atomic commit
mechanism to make this work safely.

It's possible we could give FDWs a bunch of hooks that would let them
manage post-commit cleanup the same way smgr does, but it's a far larger
project than it might have seemed.
        regards, tom lane