mysql游标的使用教程

在Student_Course数据库上，创建存储过程实现：计算每门课程的平均分，将平均分低于70分的课程号、课程名、平均分存入表fail_course中

DELIMITER $$ 
USE `student-course` $$ 
CREATE DEFINER=`root`@`localhost` PROCEDURE `cour_ave_cursor_procedure`() 
BEGIN
declare aveno char(11);
declare avename char(10);
declare avegrade float;
declare flag int;

declare courave cursor for
select course.cno,cname,avg(grade)
from course,sc
where course.cno=sc.cno
group by course.cno;

DECLARE CONTINUE HANDLER FOR
NOT FOUND SET flag=1;
set flag=0;

drop table if exists `student-course`.fail_course;
create table fail_course (aveno char(11),avename char(30), avegrade float);

open courave;
while not flag do
fetch courave into aveno,avename,avegrade;
if (not flag) then
if (avegrade<70) then
insert into fail_course()
values(aveno,avename,avegrade);
end if;
end if;
end while;
close courave;

END  $$ 
DELIMITER ;