select class
from
(
select distinct student, class
from courses
) t
group by class
having count(class)>=5
脚本如下：
select class
from
(
select distinct student, class
from courses
) t
group by class
having count(class)>=5
注意 可能有重复记录
mysql 超过5名学生的课
标签：脚本 class 重复记录 学生 超过 sele sql tin count