--创建包
create or replace package  pac_stu
as
type cur_stu is ref cursor;
procedure getStu(i in number,cur_stu out cur_stu);
end pac_stu;
--创建包体
create or replace package body pac_stu
as
procedure getStu(i in number,cur_stu out cur_stu)
as
nums number(10);
begin
select count(*) into nums from stu;    
if nums > 0 then    
open cur_stu for select * from stu;     
end if;   
end getStu;
end pac_stu;