One of my EDB colleagues, while in the process of refactoring some
unrelated Advanced Server code, discovered that (1) there's no way to
mark an aggregate as anything other than parallel-unsafe but (2) it
doesn't matter because has_parallel_hazard ignores Aggrefs anyway.
These mistakes cancel each other out (sorta) if all of your aggregates
happen to be parallel-safe, but otherwise not so much. Barring
objections, I intend to speedily apply the attached patch to fix this.
--
Robert Haas
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