elein <elein@varlena.com> writes:
> I think I want to:
> create unique index pk on table tbl (keyp1, keyp2);
> create unique index range on table tbl (keyp1, keyp2, keyp3) where keyp3 is not null;
> Are these indexes redundant given uniqueness requirement and the type of queries
> that will be run against the table?
If all (keyp1, keyp2) pairs are distinct then I see no particular use in
the second index; it doesn't check anything that's not implied by the
first index, and it doesn't offer any extra search selectivity either.
regards, tom lane