这是一个自增1的范例~~建立一个最小为1,最大为999999999的一个序列号会自动循环的序列create sequence 序列名 increment by 1 start with 1 maxvalue 999999999 cycle;当向表中插入数据时,SQL语句写法如下:SQL> insert into 表名 values(序列名.nextval,列1值,列2值);
CREATE SEQUENCE USERID INCREMENT BY 1 START WITH 1 MAXVALUE 1.0E28 MINVALUE 1 NOCYCLE NOCACHE NOORDER;CREATE OR REPLACE TRIGGER USERADD BEFORE INSERT ON MEMBERRG FOR EACH ROW BEGIN SELECT LPAD(USERID.NEXTVAL,4,'0') INTO :NEW.NUM FROM DUAL; END;
increment by 1
start with 1
maxvalue 999999999
cycle;当向表中插入数据时,SQL语句写法如下:SQL> insert into 表名 values(序列名.nextval,列1值,列2值);
MAXVALUE 1.0E28 MINVALUE 1 NOCYCLE
NOCACHE NOORDER;CREATE OR REPLACE TRIGGER USERADD
BEFORE INSERT ON MEMBERRG
FOR EACH ROW
BEGIN
SELECT LPAD(USERID.NEXTVAL,4,'0') INTO :NEW.NUM FROM DUAL;
END;