181. Employees Earning More Than Their Managers

Problem Description

Table: Employee

+-------------+---------+
| Column Name | Type    |
+-------------+---------+
| id          | int     |
| name        | varchar |
| salary      | int     |
| managerId   | int     |
+-------------+---------+
id is the primary key column for this table.
Each row of this table indicates the ID of an employee, their name, salary, and the ID of their manager.

Write an SQL query to find the employees who earn more than their managers.

Return the result table in any order.

Examples

Example 1:

Input: 
Employee table:
+----+-------+--------+-----------+
| id | name  | salary | managerId |
+----+-------+--------+-----------+
| 1  | Joe   | 70000  | 3        |
| 2  | Henry | 80000  | 4        |
| 3  | Sam   | 60000  | NULL     |
| 4  | Max   | 90000  | NULL     |
+----+-------+--------+-----------+
Output: 
+----------+
| Employee |
+----------+
| Joe      |
+----------+
Explanation: Joe is the only employee who earns more than his manager.

SELECT e1.name AS Employee
FROM Employee e1
JOIN Employee e2 ON e1.managerId = e2.id
WHERE e1.salary > e2.salary;

SELECT name AS Employee
FROM Employee e1
WHERE salary > (
    SELECT salary 
    FROM Employee e2 
    WHERE e2.id = e1.managerId
);