# create table foo( a SERIAL );
NOTICE: CREATE TABLE will create implicit sequence "foo_a_seq" for serial column "foo.a"
CREATE TABLE
# \d+ foo
Table "public.foo"
Column | Type | Modifiers | Description
--------+---------+-------------------------------------------------+-------------
a | integer | not null default nextval('foo_a_seq'::regclass) |
Has OIDs: no
AUTOINCREMENT has so many problems, that soon you'll start to love sequences so much, you'll start to hate mysql's childlish approach to problem solving :)