The Employee table holds all employees including their managers. Every employee has an Id, and there is also a column for the manager Id.
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+----+-------+--------+-----------+ | 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.
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+----------+ | Employee | +----------+ | Joe | +----------+
Solution
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SELECT E1.Name AS Employee from Employee E1, Employee E2 WHERE E1.ManagerId = E2.Id AND E1.Salary > E2.Salary