关联表的查询?
例如
a 表 (分类)
label_id label_name
1 羽毛球
2 篮球
3 足球
4 兵乓球
b表
id label_id uid
1 1 1
2 2 1
3 3 1
4 2 2
5 4 2
6 1 3
7 4 3
c表
uid name sex
1 张三 男
2 李四 女
3 王五 男
4 赵六 女
现在的要求,用户点击a表某个值 显示b表中有关的c表的记录,并显示b表的值。
例如, 用户点击a 表 中的 羽毛球( label_id为1), 根据b表得知有uid为1和3喜欢羽毛球( label_id为1的值有1和3) ,那么就显示c表中的(uid为1和3) 张三和 王五的所有属性,并将张三和王五喜欢的所有显示出来(根据B表)。要求显示结果如下:
1、张三 男 羽毛球 篮球 足球
2、王五 男 羽毛球 兵乓球
我用的是thinkphp。 该如何弄?
回复讨论(解决方案)
可以这样理解,我想知道喜欢羽毛球的有哪几个, 显示出喜欢的羽毛球的所有人后,每个人并将他们喜欢的所有运动都显示出来。
$sql="SELECT c.*,GROUP_CONCAT(a.label_name) AS sport FROM a INNER JOIN b ON a.label_id=b.label_id INNER JOIN c ON b.uid=c.uid WHERE b.uid IN(SELECT b.uid FROM a INNER JOIN b ON a.label_id=b.label_id WHERE a.label_id = 1) GROUP BY uid";M()->query($sql);
好牛啊 牛人!!

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