596. 超过5名学生的课

难度简单151

SQL架构

有一个courses 表，有: student (学生) 和 **class (课程)**。

请列出所有超过或等于5名学生的课。

例如,表:

+---------+------------+
| student | class      |
+---------+------------+
| A       | Math       |
| B       | English    |
| C       | Math       |
| D       | Biology    |
| E       | Math       |
| F       | Computer   |
| G       | Math       |
| H       | Math       |
| I       | Math       |
+---------+------------+

应该输出:

+---------+
| class   |
+---------+
| Math    |
+---------+

Note:
学生在每个课中不应被重复计算。

通过次数39,998

提交次数97,884

解题思路

这个可以使用having

select class
from courses
group by class
having count(DISTINCT student)>= 5;

答案解析

# Write your MySQL query statement below
select class
from courses
group by class
having count(DISTINCT student)>= 5;