On Sun, 2008-06-08 at 19:03 -0400, Tom Lane wrote: > Your argument seems to consider only columns having a normal > distribution. How badly does it fall apart for non-normal > distributions? (For instance, Zipfian distributions seem to be pretty > common in database work, from what I've seen.) >
If using "Idea 1: Keep an array of stadistinct that correspond to each bucket size," I would expect it to still be a better estimate than it is currently, because it's keeping a separate ndistinct for each histogram bucket. Regards, Jeff Davis -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers