mysql多个连接什么都不返回

时间:2015-02-13 13:45:59

标签: mysql

我有3张桌子:
分部(ID,分部)
团队(ID,团队)
分数(ID,RelationID,分数)
亲属(ID,RelationID,FieldID,ValID)

亲属表是为了链接' RelationID的部门和团队 FieldID定义了表格(1 =分部; 2 =团队)
ValID =给定表的ID 所以,我的fk是FieldID& amp;有效

输出应该如下所示:

  Southwest Division | Tomcats  | 17
  Southwest Division | Bears    | 12
  Northeast Division | Tomcats  | 20
  Northeast Division | Lions    | 8
  Northeast Division | Cheetahs | 13
  Southeast Division | Cheetahs | 19
  Southeast Division | Lions    | 12
  Southeast Division | Zebras   | 6 

任何特定的团队都可以在任何部门。

我的Sql是:

SELECT DISTINCT divisions.Division, teams.Team, AVG(scores.Score) AS Score FROM 
(answers INNER JOIN 
  ((relatives
    INNER JOIN divisions ON relatives.FieldID = 1 AND relatives.ValID = divisions.ID)
    INNER JOIN teams ON relatives.FieldID = 2 AND relatives.ValID = teams.ID)
        ON answers.RelationID = relatives.RelationID)
  GROUP BY Division, Team
  ORDER BY Division, Team

此sql不返回任何记录。即使我删除了答案,GROUP和ORDER BY也没有记录。

如何让表格返回我需要的? 如果需要,我会重新设计整个事物。

0 个答案:

没有答案