Re: fixing subplan/subquery confusion

Amit Kapila <amit(dot)kapila16(at)gmail(dot)com> writes:
> I had couple of questions [1] related to that patch. See if you find
> those as relevant?

I do not think those cases are directly relevant: you're talking about
appendrels not single, unflattened RTE_SUBQUERY rels.

In the subquery case, my view of how it ought to work is that Paths coming
up from the subquery would be marked as not-parallel-safe if they contain
references to unsafe functions. It might be that that doesn't happen for
free, but my guess is that it would already work that way given a change
similar to what I proposed.

In the appendrel case, I tend to agree that the easiest solution is to
scan all the children of the appendrel and just mark the whole thing as
not consider_parallel if any of them have unsafe functions.

regards, tom lane