Question

CREATE VIEW Tournament_Winners AS
SELECT tournament_no, player_no FROM Results WHERE position = 1
SELECT tornament_name FROM Tournament WHERE Tournamnet.tournament_no = Results.tournament_no;

我还尝试使用JOIN实现这个：

SELECT tournament_no, player_no FROM Results WHERE position = 1
FULL JOIN Tournament
ON Tournament.tournament_no = Results.tournament_no;

都没有效果。

Answer 1

查看joins和view的语法。

CREATE OR REPLACE VIEW Tournament_Winners AS
      SELECT a.tournament_no, a.player_no, b.tornament_name
         FROM Results a,Tournament b 
            where a.tournament_no=b.tournament_no and a.position=1

Answer 2

对于前一个视图中的前两个结果不起作用

对于第二个，您需要处理语法/顺序

SELECT
FROM 
WHERE
GROUP BY
ORDER BY
HAVING

SELECT tournament_no, player_no 
FROM Results 
FULL JOIN Tournament
ON Tournament.tournament_no = Results.tournament_no
WHERE position = 1

我的Oracle View有什么问题？

2 个答案: