Question

我需要编写一个包含两个外键到另一个表的查询。我需要查看它们并从ID中获取名称。我有一个查询，但我将每个作为单独的记录返回。

SELECT Teams.team_name, Games.ID, Games.game, Games.date, Games.time, Games.team_one, Games.team_two, Games.pts 
FROM Teams, Games 
WHERE Teams.ID = Games.team_one OR Teams.ID = Games.team_two 
ORDER BY Games.ID ASC

所以Games.team_one和Games.team_two是我的Teams表的外键。我需要取回一条记录：

Games.ID，Games.game，Games.date，Games.time，Games.team_one，Games.team_two，Team1 Name，＆amp;第二队名称

现在我收到两条相同的记录，但team_name不同。如何为team_one_name和team_two_name创建一个动态字段，以便根据Games.team_one＆amp; Games.team_two并将它们作为同一记录的一部分？

感谢您的帮助。

凯文

Answer 1

使用首选的ANSI样式连接语法：

SELECT t1.team_name AS team_one_name, 
       t2.team_name AS team_two_name, 
       games.id,
       games.game, 
       games.date,
       games.time, 
       games.team_one,
       games.team_two, 
       games.pts
FROM   games 
INNER JOIN teams t1 ON t1.id = games.team_one 
INNER JOIN teams t2 ON t2.id = games.team_two 
ORDER BY games.id ASC

Answer 2

我认为你应该使用GROUP BY子句

Answer 3

只需使用别名以不同的名称加入表团队两次：

 SELECT t1.team_name as   
 team_one_name, t2.team_name as  
 team_two_name, Games.ID,
 Games.game, Games.date,
 Games.time, Games.team_one,
 Games.team_two, Games.pts 
 FROM Teams t1, Teams t2, Games 
 WHERE t1.ID = Games.team_one OR  
   t2.ID = Games.team_two 
 ORDER BY Games.ID ASC

创建字段所需的SQL查询帮助

3 个答案: