marcin mank <marcin.mank@xxxxxxxxx> writes: > I hit an interestinhg paper on n_distinct calculation: > http://www.pittsburgh.intel-research.net/people/gibbons/papers/distinct-values-chapter.pdf I don't think we're quite ready to make ANALYZE read every row of a table in order to estimate n_distinct. It is an interesting paper in that it says that you have to do that in order to get *provably* good estimates, but I've not abandoned the hope of getting *usually* good estimates without so much work. regards, tom lane -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
