[Oracle] Oracle中使用触发器(trigger)和序列(sequence)模拟实现自增列实例

create table user  
(   
  id   number(6) not null,   
  name   varchar2(30)   not null primary key  
)

create sequence user_seq increment by 1 start with 1 minvalue 1 maxvalue 9999999999999 nocache order;

create or replace trigger user_trigger   
before insert on user  
for each row   
begin  
    select   user_seq.nextval  into:new.id from sys.dual ;   
end;