Re: review: FDW API

I wrote:
> ... My feeling is it'd be best to pass down
> all the information the executor node has got --- probably we should
> just pass the ForeignScanState node itself, and leave a void * in that
> for FDW-private data, and be done with it.  Otherwise we're going to be
> adding missed stuff back to the API every time somebody notices that
> their FDW can't do X because they don't have access to the necessary
> information.

Attached is a rewritten version of fdwhandler.sgml that specifies what I
think is a more future-proof API for the callback functions.  Barring
objections, I'll push ahead with editing the code to match.

			regards, tom lane