1建立数据表
Code
create table Test_Increase(
userid number(10) primary key, /*主键,自动增加*/
username varchar2(20)
);
2创建自动增长序列
CREATE SEQUENCE TestIncrease_Sequence
INCREMENT BY 1 -- 每次加几个
START WITH 1 -- 从1开始计数
NOMAXVALUE -- 不设置最大值
NOCYCLE -- 一直累加,不循环
CACHE 10;
3创建触发器
CREATE TRIGGER Test_Increase BEFORE
insert ON Test_Increase FOR EACH ROW
begin
select TestIncrease_Sequence.nextval into:New.userid from dual;
end;
4 提交
commit;
5 测试
反复执行如下语句:
insert into Test_Increase(Username) values('test')
6 查看插入结果:
userid username
1 test
2 test
3 test
4 test
5 test
6 test
7 test
8 test
9 test