Task: Text to Code
Input (English): SQL: SELECT staff_id , staff_name FROM Staff GROUP BY staff_id ORDER BY Count ( * ) Asc LIMIT 1
Feedback: In step 1 for each staff id in staff department assignments , find difference between date assigned to and date assigned from .
Output (English): SELECT T1.staff_id ,  T1.staff_name FROM staff AS T1 JOIN Staff_Department_Assignments AS T2 ON T1.staff_id  =  T2.staff_id ORDER BY date_assigned_to - date_assigned_from LIMIT 1