2016.23

游标的4个属性：

 1. %isopen 判断游标是否打开
 2. %rowcount 影响的行
 3. %found 还有下一条数据
 4. %notfound 没有下一条数据

--根据员工的职位涨工资，总裁涨1000，经理涨800，其他涨400
2 declare
3 cursor cemp is select empno,job from emp;
4 pempno emp.empno%type;
5 pjob emp.job%type;
6 begin
7 open cemp;
8 loop
9 fetch cemp into pempno,pjob;
10 exit when cemp%notfound;
11 if pjob ='PRESIDENT' then update emp set sal = sal + 1000 where empno = pempno;
12 elsif pjob='MANAGER' then update emp set sal = sal + 800 where empno = pempno;
13 else
14 update emp set sal = sal + 400 where empno = pempno;
15 end if;
16 end loop;
17 close cemp;
18* end;