primary key

Sandeep Joshi <sjoshi@Zambeel.com> writes:

When we specify "primary key" while creating a table, what kind of
index is created?

btree.

btree is the default index type in all cases in Postgres. It's
considerably better tested than the other types, as well as better-
performing under concurrent access. That's not necessarily an
inherent property of btrees in general, but I think it's a safe
comment about the code that actually exists in Postgres...

regards, tom lane