SQL错误：ORA-00918：列模糊定义

Question

请帮我看看我在这里做错了什么：

从第1行开始出错：命令中为1 -

CREATE VIEW VW_ROUTE AS
  SELECT ROUTE_NAME
       , FARE
       , DESTINATION
       , ROUTE_ID
       , STOP_NAME
       , TERMINUS
       , NUMBER_OF_STOPS
  FROM STOPS S
    LEFT JOIN ROUTE R
        ON S.ROUTE_ID = R.ROUTE_ID
 WHERE NUMBER_OF_STOPS > ('1')

 Error at Command Line : 5 Column : 10 Error report - SQL Error: ORA-00918: column ambiguously defined 00918. 00000 - "column ambiguously defined" *Cause: *Action: 

Answer 1

两个表中都有相同的列名。 添加别名。

CREATE VIEW VW_ROUTE AS
SELECT ROUTE_NAME
       , FARE
       , DESTINATION
       , S.ROUTE_ID          -- ROUTE_ID exists in table STOPS/ROUTE
       , STOP_NAME
       , TERMINUS
       , NUMBER_OF_STOPS
FROM STOPS S
LEFT JOIN ROUTE R
  ON S.ROUTE_ID = R.ROUTE_ID
WHERE NUMBER_OF_STOPS > ('1');

好的做法是在所有出现时使用别名以避免歧义。