oracle中使用序列实现id自增

conn scott/tiger@db890
1、创建序列
create sequence foo_id_seq
nocycle
maxvalue 9999999999
start with 1;
2、使用触发器自增
drop table foo;
create table foo(
  id number primary key,
  data varchar2(100));

create or replace trigger 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');