None
SELECT p.project_id,
p.employee_id
FROM Project p
JOIN Employee e
ON p.employee_id = e.employee_id
WHERE (p.project_id, e.experience_years) IN
(SELECT p.project_id,
max(e.experience_years) AS max_years
FROM Project p
JOIN Employee e
ON p.employee_id = e.employee_id
GROUP BY p.project_id)