Re: ecxt_scantuple has wrong TupleDesc

peter(dot)trautmeier(at)gmx(dot)de writes:
> I wonder why my ecxt_scantuple has a TupleDesc matching the subplan's
> tlist, not my plan's tlist.

That's the way it's supposed to be --- the scantuple slot is for
scanning your subplan's output.

> I have written a new executor node Foo, with corresponding ExecFoo and make_foo functions. I have also written a new Expr type called Bar, along with a ExecEvalBar.

> In make_foo I append some Bar columns. When I try to evaluate the Bar columns in ExecFoo via ExecProject, I need the Bar columns to access each other.

That makes no sense at all. ExecProject can't be expected to access
output columns of the current node --- they haven't been computed yet.

regards, tom lane