SELECT 或 JOIN 使用同一列两次

Question

所以我有三个 table：员工、秘书和经理

给定架构

Employee table 有以下列：

Employee_Number
姓名
家庭住址
电话号码

Secretary table 包含：

Secretary_Number
Employee_Number（用外键链接到 Employee table）
Manager_Number（与管理器 table 的外键链接）

Managertable包含：

Manager_Number
Employee_Number（用外键链接到 Employee table）

需要什么以及我尝试了什么

我正在尝试执行 JOIN 以便我可以看到以下列：

秘书号码
秘书姓名
经理编号
经理姓名

我有以下连接语句，它显示了所有列，并显示了 Secretary's name 和 number，以及经理编号:

SELECT
  SECRETARY.SECRETARY_NUMBER, 
  SECRETARY.EMPLOYEE_NUMBER AS SECRETARY_EMPLOYEE,
  EMPLOYEE.NAME AS SECRETARY_NAME,
  SECRETARY.MANAGER_NUMBER, 
  MANAGER.EMPLOYEE_NUMBER AS MANAGER_EMPLOYEE,
  EMPLOYEE.NAME AS MANAGER_NAME
FROM SECRETARY, MANAGER, EMPLOYEE
WHERE SECRETARY.MANAGER_NUMBER = MANAGER.MANAGER_NUMBER
AND SECRETARY.SECRETARY_NUMBER = EMPLOYEE.EMPLOYEE_NUMBER
AND MANAGER.EMPLOYEE_NUMBER = EMPLOYEE.EMPLOYEE_NUMBER;

问题

但是我无法显示经理姓名，或者不重复与秘书姓名相同的信息。

如有任何帮助，我们将不胜感激！

Answer 1

SELECT
  s.SECRETARY_NUMBER, 
  s.EMPLOYEE_NUMBER AS SECRETARY_EMPLOYEE,
  e.NAME AS SECRETARY_NAME,
  s.MANAGER_NUMBER, 
  m.EMPLOYEE_NUMBER AS MANAGER_EMPLOYEE,
  e2.NAME AS MANAGER_NAME
FROM 
  SECRETARY s
INNER JOIN
  EMPLOYEE e
ON
  e.EMPLOYEE_NUMBER = s.EMPLOYEE_NUMBER
INNER JOIN
  MANAGER m
ON
  m.EMPLOYEE_NUMBER = s.MANAGER_NUMBER
INNER JOIN
  EMPLOYEE e2
ON
 e2.EMPLOYEE_NUMBER = m.EMPLOYEE_NUMBER;

SELECT 或 JOIN 使用同一列两次

SELECT or JOIN using same column twice

sql

oracle11g

给定架构

需要什么以及我尝试了什么

问题