Self-Join for Hierarchies

MediumSQL · PostgreSQL

Problem

Write a query using a self-join to find employees who earn more than their managers.

Use the employees table and compare each employee's salary with the salary of the employee referenced by manager_id. Exclude employees without a manager or without a comparable salary.

Output

One row per employee earning more than their manager
Columns: employee_id, employee_name, employee_salary, manager_name, manager_salary
Sort by employee_id ascending

Schema

employees

Column	Type	Description
employee_idPK	INT	Unique employee identifier
employee_name	VARCHAR(100)	Employee's full name
manager_id	INT	Employee ID of the person's manager
salary	DECIMAL(12,2)	Annual employee salary

Tablesemployees

CodePostgreSQL

You need to log in / sign up to run or submit.Ln 1

Run your query to see results here.