Robert Haas <robertmhaas@gmail.com> writes:
> Oh, one other thing about this: I'm not going to try to defend
> whatever confusion between subplans and subqueries appears in that
> comment, but prior to upper planner pathification I think we were dead
> in the water here anyway, because the subquery was going to output a
> finished plan, not a list of paths. Since finished plans aren't
> labeled as to parallel-safety, we'd have to conservatively assume that
> the finished plan we got back might not be parallel-safe. Now that
> we're using the path representation throughout, we can do better.
Well, if that were still the state of affairs, we could certainly consider
adding a parallel_safe flag to Plans as well as Paths. But as you say,
it's moot now.
regards, tom lane