Postgres 12

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CREATE TABLE employees (
	employee_id serial PRIMARY KEY,
	full_name VARCHAR NOT NULL,
	manager_id INT,
	age INT NOT NULL
);
INSERT INTO employees (
	employee_id,
	full_name,
	manager_id,
	age
)
VALUES
	(1, 'Michael North', NULL, 24),
	(2, 'Megan Berry', 1, 20),
	(3, 'Sarah Berry', 1, 31),
	(4, 'Zoe Black', 1, 25),
	(5, 'Tim James', 1, 33),
	(6, 'Bella Tucker', 2, 22),
	(7, 'Ryan Metcalfe', 2, 19),
	(8, 'Max Mills', 2, 36),
	(9, 'Benjamin Glover', 2, 33),
	(10, 'Carolyn Henderson', 3, 40),
	(11, 'Nicola Kelly', 3, 27),
	(12, 'Alexandra Climo', 3, 21),
	(13, 'Dominic King', 3, 44),
	(14, 'Leonard Gray', 4, 25),
	(15, 'Eric Rampling', 4, 36),
	(16, 'Piers Paige', 7, 30),
	(17, 'Ryan Henderson', 7, 20),
	(18, 'Frank Tucker', 8, 35),
	(19, 'Nathan Ferguson', 8, 49),
	(20, 'Kevin Rampling', 8, 50)
20 rows affected

WITH RECURSIVE subordinates AS (
    SELECT
        employee_id,
        manager_id
    FROM
        employees
    WHERE
        employee_id = 2
    UNION
    SELECT
        e.employee_id,
        e.manager_id
    FROM
        employees e
    INNER JOIN subordinates s 
        ON s.employee_id = e.manager_id
    WHERE
       e.age >= 30
) 

SELECT e.full_name
FROM subordinates
INNER JOIN employees AS e 
    ON e.employee_id = subordinates.employee_id;


full_name


Megan Berry

Max Mills

Benjamin Glover

Frank Tucker

Nathan Ferguson

Kevin Rampling