講解Oracle數據庫自動增長列的實現過程
◆1.創建序列
-- Create sequence create sequence INNERIDminvalue 1maxvalue 99999999999999start with 1increment by 1cache 20order;
◆2.--INNERID.currval 指當前序列
--INNERID.nextval 指下一個序列
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));
--不斷的插入序列的下一個值.
◆3.創建觸發器(注:此處無法設置id的默認值為INNERID.nextval )
CREATE OR REPLACE TRIGGER admin_tg--admin id 的觸發器BEFORE INSERT ON admin FOR EACH ROWBEGINSELECT INNERID.NEXTVAL INTO :NEW.id FROM DUAL;END;
測試語句如下:
insert into admin (username) values ( 'zdz');
成功插入數據,再查看數據,你可以發現id自動增長了,此問題至此解決!
