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 | Salary | ManagerId |+----+-------+--------+-----------+| 1 | Joe | 70000 | 3 || 2 | Henry | 80000 | 4 || 3 | Sam | 60000 | NULL || 4 | Max | 90000 | NULL |+----+-------+--------+-----------+
Given the Employee table, write a SQL query that finds out employees who earn more than their managers. For the above table, Joe is the only employee who earns more than his manager.
+----------+| Employee |+----------+| Joe |+----------+
题目解答：
select E1.Name from Employee as E1, Employee as E2 where E1.ManagerId = E2.Id and E1.Salary > E2.Salary