Problem: 570. 至少有5名直接下属的经理

👨‍🏫 参考题解

🍻子查询

select name  
from Employee
where id in(
    select managerId 
    from Employee 
    group by managerId 
    having managerId != 'null' and count(*) >= 5);

🍻 join 虚拟表

select Employee.Name as Name
from (
  select ManagerId as Id
  from Employee
  group by ManagerId
  having count(Id) >= 5
) as Manager join Employee
on Manager.Id = Employee.Id