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

Workday's HR team is generating an org chart report and needs every employee paired with their manager's name. Using the employees table, return each employee's name alongside their manager's name - employees with no manager should still appear 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 Input

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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