The Employee table holds all employees including their managers. Every employee has an Id, and there is also a column for the manager Id.
+------+----------+-----------+----------+ |Id |Name |Department |ManagerId | +------+----------+-----------+----------+ |101 |John |A |null | |102 |Dan |A |101 | |103 |James |A |101 | |104 |Amy |A |101 | |105 |Anne |A |101 | |106 |Ron |B |101 | +------+----------+-----------+----------+
Given the Employee table, write a SQL query that finds out managers with at least 5 direct report. For the above table, your SQL query should return:
+-------+ | Name | +-------+ | John | +-------+
Note:
No one would report to himself.
select name
from Employee
where Id in
(select e1.ManagerId
from Employee e1
group by e1.ManagerId
having count(*)>= 5)；