如何为oracle中的表增加像sqlserver一样的自动列

conn scott/tiger@powermis

drop table foo;

create table foo(

id number primary key,

data varchar2(100));

create sequence foo_seq;

create or replace trigger bifer_foo_id_pk

before insert

on foo

for each row

begin

select foo_seq.nextval into :new.id from dual;

end;

/

insert into foo(data)

values('Chirstopher');

insert into foo(id,data)

values(5,'Sean');

select * from foo;