PostgreSQL Subquery: Find the name of the employees who are managers
4. Write a SQL subquery to find the first_name and last_name of the employees who are working as a manager.
SELECT first_name, last_name FROM employees WHERE (employee_id IN (SELECT manager_id FROM employees));
Sample table: employees
pg_exercises=# SELECT first_name, last_name pg_exercises-# FROM employees pg_exercises-# WHERE (employee_id pg_exercises(# IN (SELECT manager_id pg_exercises(# FROM employees)); first_name | last_name ------------+----------- Alexander | Hunold Den | Raphaely Steven | King Neena | Kochhar Payam | Kaufling Shanta | Vollman Kevin | Mourgos John | Russell Karen | Partners Alberto | Errazuriz Gerald | Cambrault Eleni | Zlotkey Lex | De Haan Matthew | Weiss Adam | Fripp Nancy | Greenberg Michael | Hartstein Shelley | Higgins (18 rows)
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