There is a table courses with columns: student and class
Please list out all classes which have more than or equal to 5 students.
For example, the table:
+———+————+ | student | class | +———+————+ | A | Math | | B | English | | C | Math | | D | Biology | | E | Math | | F | Computer | | G | Math | | H | Math | | I | Math | +———+————+
Should output:
+———+ | class | +———+ | Math | +———+
Link: https://leetcode.com/problems/classes-more-than-5-students/
Solution #
select class from courses group by class having count(distinct student) >= 5;