表关联取值问题！

Question

Q: 146 Examine the structure of the EMPLOYEES and DEPARTMENTS tables:EMPLOYEES
EMPLOYEE_ID NUMBER
DEPARTMENT_ID NUMBER
MANAGER_ID NUMBER
LAST_NAME VARCHAR2(25)DEPARTMENTS
DEPARTMENT_ID NUMBER
MANAGER_ID NUMBER
DEPARTMENT_NAME VARCHAR2(35)
LOCATION_ID NUMBERYou want to create a report displaying employee last names, department names, and locations. Which
query should you use?A. SELECT e.last_name, d. department_name, d.location_id
FROM employees e NATURAL JOIN departments D
USING department_id ;B. SELECT last_name, department_name, location_id
FROM employees NATURAL JOIN departments
WHERE e.department_id =d.department_id;C. SELECT e.last_name, d.department_name, d.location_id
FROM employees e NATURAL JOIN departments d;D. SELECT e.last_name, d.department_name, d.location_id
FROM employees e JOIN departments d
USING (department_id );Answer: D答案A为什么是错的呢？

Answer 1

A错了，因为using的话要带()符号将字段包起来。