570. 至少有5名直接下属的经理 题解

# Write your MySQL query statement below

select name

from(

    select e1.name,count(*) c

    from Employee e1

    cross join Employee e2

    on e1.id = e2.managerId and e1.id != e2.id

    group by e1.id

) e

where c >= 5

名字可能会相同，应该以id这个主键作为区分