Andrew Dunstan <andrew@dunslane.net> writes:
> I have a couple of questions, however. First, in that long list of
> alternatives for a Plan node, can any of them occur more than once?
No.
> Second, we are using Item as a child of both Output and Sort-Key nodes.
> Are they really describing the same thing? And in any case, Item is a
> wonderfully non-informative name, as is Output, for that matter.
They are both describing expressions. I wanted to rename Item as Expr,
if you'll recall. But I think we should have a concrete plan about
all the tweaks we want to make to the output schema before doing
anything, so I haven't pushed to change it immediately.
I don't see anything wrong with Output --- what else would you call the
output expressions of a node?
regards, tom lane