Alex Pilosov wrote:
> On Wed, 27 Jun 2001, Jan Wieck wrote:
>
> > Alex Pilosov wrote:
> > > On Thu, 28 Jun 2001, Hannu Krosing wrote:
> > > >
> > > > How hard would it be to turn this around and implement RETURN AND
> > > > CONTINUE
> > > > for at least PL/PGSQL, and possibly C/Perl/Python ... ?
> > > Cannot talk about plpgsql, but for c this would be probably implemented
> > > with setjmp and with perl with goto. Probably not very complex.
> >
> > Don't think so. When the function returns, the call stack
> > get's destroyed. Jumping back to there - er - the core dump
> > is not even useful any more. Or did I miss something?
>
> Well, it shouldn't return, but instead save the location and longjmp to
> SPI_RESUME_jmp location. On a next call, instead of a function call, it
> should longjmp back to saved location. I have to admit its more complex
> than I originally thought, but probably doable.
OK, let's screw it up some more:
SELECT F.a, B.b FROM foo() F, bar() B WHERE F.a = B.a;
This should normally result in a merge join, so you might get away with longjmp's. But you get the idea.
Jan
--
#======================================================================#
# It's easier to get forgiveness for being wrong than for being right. #
# Let's break this rule - forgive me. #
#================================================== JanWieck@Yahoo.com #
_________________________________________________________
Do You Yahoo!?
Get your free @yahoo.com address at http://mail.yahoo.com