学游标

//显示游标  loop 
declare
         cursor cur_stu is select* from student;
         c_ cur_stu%rowtype;
BEGIN
       if cur_stu%isopen then
       CLOSE cur_stu;
       end if ; 
       open cur_stu;
       LOOP
       fetch cur_stu into c_;
       exit when cur_stu%NOTFOUND;
       dbms_output.put_line(c_.stuname);
       end loop;
end;
//显示游标  for
create or replace procedure pro_stu2 as
begin
  declare
           cursor cur_stu is select stuno ,stuname from student order by stuno;
   BEGIN
         for stu in cur_stu
         loop
         dbms_output.put_line(stu.stuname);
         end loop;
   end;
end pro_stu2;
// 执行  begin  pro_stu2(); end ;
//强型游标
declare
   type pro_cur is ref cursor return student%rowtype; --返回student 列
      p_c  pro_cur ;   -- 实例化游标
      s student%rowtype;
      begin
      open p_c for select *from student ;
      loop
      fetch p_c into  s;
      exit when p_c%notfound;
      dbms_output.put_line(p_c%rowcount||' '||s.stuname||' '||s.age);
      end loop;
      close p_c;
end;