Jeremy Harris <j...@wizmail.org> writes: > On 22/01/14 03:53, Tom Lane wrote: >> Jon Nelson <jnelson+pg...@jamponi.net> writes: >>> - in createplan.c, eliding duplicate tuples is enabled if we are >>> creating a unique plan which involves sorting first
>> [ raised eyebrow ... ] And what happens if the planner drops the >> unique step and then the sort doesn't actually go to disk? > I don't think Jon was suggesting that the planner drop the unique step. Hm, OK, maybe I misread what he said there. Still, if we've told tuplesort to remove duplicates, why shouldn't we expect it to have done the job? Passing the data through a useless Unique step is not especially cheap. regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers