On Sun, 2009-09-20 at 19:42 -0400, Tom Lane wrote:
> Jeff Davis <pgsql(at)j-davis(dot)com> writes:
> > I suppose I should just allow any index_elem. The only way I was able to
> > make the grammar for that work is by using a reserved keyword. The
> > possibilities that make the most sense to me are:
>
> > index_elem WITH any_operator
> > index_elem WITH OPERATOR any_operator
> > index_elem CHECK any_operator
> > index_elem CHECK OPERATOR any_operator
>
> > Do any of these look acceptable?
>
> I'd vote for "CHECK", out of that list. WITH has no mnemonic value
> whatever.
Using CHECK as part of the syntax of an EXCLUSION constraint will surely
confuse the whole thing with CHECK constraints.
USING OPERATOR is available, I think.