Oracle笔记 四、增删改、事务

Oracle笔记 四、增删改、事务

1、插入
insert into dept values(50, ‘soft’, ‘Guangzhou’);
insert into dept(deptno, dname) values(60, ‘software test’);
insert into dept select * from dept where deptno = 20;

2、删除
delete from dept where deptno = 20;
delete from dept;

3、修改
update dept set dname = dname || ‘ ^.^’ where deptno = 20;

4、事务
每个修改语句完成后都可以回滚或提交,即rollback、commit;
eg:
insert into dept values(50, ‘soft’, ‘Guangzhou’);
rollback;
这样就回滚了,等于上面的没有插入;如果commit就提交了,此后如果再rollback也无力回天了。
下面这样也是无法回滚的:
insert into dept values(50, ‘soft’, ‘Guangzhou’);
create table temp as select * from dept;
rollback;
再次查询,发现无法回滚;同样增删改后面运行grant/create语句也是无法回滚的;

版权维护转载hoojo博客的。