Re: [HACKERS] subselects coding started

Thomas G. Lockhart wrote:
>
> Bruce Momjian wrote:
>
> > OK, I have created the SubLink structure with supporting routines, and
> > have added code to create the SubLink structures in the parser, and have
> > added Query->hasSubLink.
> >
> > I changed gram.y to support:
> >
> >         (x,y,z) OP (subselect)
> >
> > where OP is any operator.  Is that right, or are we doing only certain
> > ones, and of so, do we limit it in the parser?
>
> Seems like we would want to pass most operators and expressions through
> gram.y, and then call elog() in either the transformation or in the
> optimizer if it is an operator which can't be supported.

Not in optimizer, in parser, please.
Remember that for <> SubLink->useor must be TRUE and this is parser work
(optimizer don't know about "=", "<>", etc but only about Oper nodes).

IN ("=" ANY) and NOT IN ("<>" ALL) transformations are also parser work.

Vadim