On Sat, Oct 26, 2013 at 12:02 PM, Andres Freund <andres@2ndquadrant.com> wrote:
> Imo what it does looks sane - it adds parentheses whenever a child of a
> set operation is a set operation again to make sure the order in which
> the generated set operations are parsed/interpreted stays the same.
But UNION ALL is associative.
--
Robert Haas
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