Michael Glaesemann <grzm@seespotcode.net> writes:
> AIUI, the stress is on the *can*, with a meaning of "may", right? Not
> all SQL functions can be inlined.
In particular, I think the OP was thinking of a function returning set,
which we currently don't inline at all. I believe this is doable, but
perhaps not entirely trivial. I seem to recall looking into it a year
or two ago, and hitting some roadblocks that I can't remember the
details of ...
regards, tom lane