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 | +----------+
1 # Write your MySQL query statement below 2 SELECT a.NAME FROM Employee a, Employee b 3 WHERE a.ManagerId = b.Id AND a.Salary > b.Salary;
LeeCode(Database)-Employees Earning More Than Their Managers
原文：http://www.cnblogs.com/vpoet/p/4679612.html