Gregory Stark <stark(at)enterprisedb(dot)com> writes:
> I could imagine problems the planner would have to deal with though, such as
> what type is "bogon" in this query?
> WITH RECURSIVE x(bogon) AS (select bogon from x) select * from x;
Just a note --- that's not the planner's problem, either. Semantic
interpretation of the meaning of a query is supposed to be completed
during parse analysis.
regards, tom lane