แสดงรหัสพนักงานทุกคนที่ไม่ทำลายเอกสารใดๆ
Show the ids of all employees who don't destroy any document.
df_employees = pd.DataFrame(columns=['employee_id', 'Destroyed_by_Employee_ID']); df_docs_destroyed = pd.DataFrame(columns=['employee_id', 'Destroyed_by_Employee_ID'])
df_employees[~df_employees['employee_id'].isin(df_docs_destroyed['Destroyed_by_Employee_ID'])]['employee_id']