如何INNER JOIN超过两个类别？

Question

我在这里有点困惑，需要一些帮助...

情况是我已经制作了三个表（fr_Leagues，fr_nations和fr_confeds），我要做的就是添加一个联赛，该联赛显示类别的名称而不是带有分页的id。 这是代码：

现在修复！

  "SELECT 
 a.id as confed_id,
 a.fr_short_name as confed_name, 
     b.id as nation_id,
 b.fr_name as nation_name,
 c.id as league_id,
 c.fr_name as league_name"
." FROM fr_confeds as a 
INNER JOIN fr_nations as b ON a.id = b.confed_id 
INNER JOIN fr_leagues as c ON b.id = c.nation_id"
." LIMIT $paginate->start, $paginate->limit"

Answer 1

您缺少如何将不同的表链接在一起的信息。 在每个INNER JOIN上，您都需要拥有它：

INNER JOIN fr_nations ON a.<someColumn> = b.<anotherColumn> INNER JOIN fr_leagues ON a.<someColumn> = b.<anotherColumn>

Answer 2

使用此查询

SELECT * FROM fr_confeds为A

内联接fr_nations为B ON A.id = B.confed_id

INNER JOIN fr_leagues作为C ON B.confed_id = C.league_id

LIMIT $ paginate->开始，$ paginate-> limit