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 |
+----------+
本题是有一张表Employee,表中包含employee和他们的manager,分别有name列、Salary列和ManagerId列,需要找出employee比自己的manager领的薪水高的employee:
解法一:
select e1.Name as employee from employee e1,employee e2
where e1.ManagerId = e2.Id and e1.Salary > e2.Salary;
解法二:
select e1.Name as employee from employee e1
join employee e2 on e1.ManagerId = e2.Id
where e1.Salary > e2.Salary;
转载于:https://www.cnblogs.com/lsyb-python/p/11074414.html