Employee and Manager Name Pairs - Easy SQL Self Joins Interview Problem

Problem

Every employee record stores a manager_id that points to another row in the same table. Using the employees table, return each employee's name alongside their manager's name. Employees with no manager should still appear in the result with NULL for the manager name.

Return employee_name and manager_name, sorted by employee_name.

Schema

employees

column	type
id	INTEGER
name	TEXT
manager_id	INTEGER

manager_id is NULL for employees at the top of the org chart.

Sample Data

id	name	manager_id
1	Alice	NULL
2	Bob	1
3	Carol	1
4	Dave	2

Expected Output

employee_name	manager_name
Alice	NULL
Bob	Alice
Carol	Alice
Dave	Bob

Explanation

Alice reports to nobody, so her manager is NULL. Bob and Carol both report to Alice. Dave reports to Bob.

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