Robert Haas <robertmhaas@gmail.com> writes:
> ... we could leave the parentheses out in
> whichever case it's equivalent to.
Ah, I see what you're getting at now. Yeah, that might be a useful
readability improvement.
> ... I fairly commonly
> write queries that involve multiple UNION ALL branches and, no matter
> how clever we are, having that lead to progressively deeper nesting at
> each level is not going to look nice.
Agreed. I was wondering myself whether we couldn't fix things so that
all the branches are indented the same, even with parens.
regards, tom lane