Elielson Fontanezi <ElielsonF@prodam.sp.gov.br> writes:
> Hum... What such thing strange.
> Hash algorithms should be better than BTREE and RTREE algorithms.
Perhaps. The problem with Postgres' hash indexes is that no one has
worked on the hash-index code since Berkeley days (except for one or
two minor bugfixes, I think). The btree code has gotten a lot more
care and attention, so it is now much better than the hash code.
I'm not sure whether it's really worth anyone's time to try to
bring the hash index code up to speed. It *might* be better
than btree for certain limited applications, if it were equally
well implemented. Or it might not. You'd have to invest a lot
of work to find out, and might well discover that your work
was wasted.
regards, tom lane