conn scott/tiger@localhost droptable foo; createtable foo ( id numberprimarykey, data varchar2(100) ); create sequence foo_seq; createorreplacetrigger bifer_foo_id_pk before insert on foo for each row begin select foo_seq.nextval into :new.id from dual; end; / insertinto foo(data) values(’Chirstopher’); insertinto foo(id,data) values(5,’Sean’); select*from foo;