讲解Oracle数据库自动增长列的实现过程

-- Create sequence create sequence INNERIDminvalue 1maxvalue 99999999999999start with 1increment by 1cache 20order;

insert into admin values (INNERID.nextval,'a');insert into admin values (INNERID.nextval,'b');insert into admin values (INNERID.nextval,'c');insert into admin values (INNERID.nextval,'d');create table admin(id varchar2(20),name varchar2(10));

CREATE OR REPLACE TRIGGER admin_tg--admin id 的触发器BEFORE INSERT ON admin FOR EACH ROWBEGINSELECT INNERID.NEXTVAL INTO :NEW.id FROM DUAL;END;

insert into admin (username) values ( 'zdz');