Oracle使用游标更新数据

###使用游标修改数据

####定义一个游标，游标名称为 mycursor

#####更新scott用户中emp表中empno为7369的销售额

-- Created on 2015/11/30 by ZHANW 
declare 
  he emp%rowtype;
  cursor mycursor(pid integer) is select * from emp where empno = pid for update;
begin
  open mycursor(7369);
  while(true) loop
     fetch mycursor into he; 
     exit when mycursor%notfound;
     update emp set sal = 1111 where current of mycursor;
  end loop;
end;

-- Created on 2015/11/30 by ZHANW 
declare 
  he emp%rowtype;
  cursor mycursor(pid integer) is select * from emp where empno = pid for update;
begin
  open mycursor(7369);
  while(true) loop
     fetch mycursor into he; 
     exit when mycursor%notfound;
     delete from emp where current of mycursor;
  end loop;
end;

###注意：

delete语句一定要写在exit后面，不然可能会报错。

####优化：

在定义游标时，可以在for update 后面添加 of 字段或者nowait。