Garfield Lewis <garfield.lewis@lzlabs.com> writes:
> I think you are right in the case of INPUT/RECEIVE, however we should be able to get that info during OUTPUT/SEND (I
think)since it is fixed at that point. At the time I return the information to the user I could augment the output to
addthat information to the output. However, I still don't know if it is even possible to get that information in those
functions.Is that at all possible?
No, it's the same problem in reverse: the output function cannot
know where the value came from. There is no hard and fast
reason that it must have come out of a table, either. Consider
something as simple as
SELECT 'blah blah'::yourtype;
This'll invoke the type's input function to parse the literal string,
and later it'll invoke the output function to reconstruct a string
to send to the client, and there's no table involved.
regards, tom lane
