SELECT e.id, e.employee_id, e.position, e.hire_date, e.status,
            CONCAT(u.first_name, " ", u.last_name) as full_name,
            u.email,
            d.name as department_name
     FROM employees e
     LEFT JOIN users u ON e.user_id = u.id
     LEFT JOIN departments d ON e.department_id = d.id