181. Employees Earning More Than Their Managers (Easy)

Source: https://leetcode.com/problems/employees-earning-more-than-their-managers/#/description
Description:

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 |
+----------+

 

Solution:

select t0.name as Employee from
Employee t0 join
Employee t1
on t0.managerid = t1.id
and t0.salary>t1.salary