mysql - 我们如何在事件记录中进行多重连接 Codeigniter

Question

大家好，作为数据库和 Codeigniter 的初学者，您能帮帮我吗？我们如何在事件记录中编写这个多内连接和左连接查询。

SELECT suppliers.*, category.strCategory, category_1.strCategory AS strParent, 
tblcitylist.city_name
FROM ((suppliers INNER JOIN category ON suppliers.intCat=Category.intId) INNER JOIN tblcitylist ON 
suppliers.intCity=tblcitylist.city_id) LEFT JOIN category AS category_1 ON 
category.intParent=Category_1.intId
WHERE status='y';

我有三个表 suppliers、tblcitylist 和 category。想要获取具有 intCat 和 intCity 的供应商的数据，结果是具有城市名称(city_name)和类别名称(strCategory)的供应商表的数据。谢谢

Answer 1

也许这就是你想要的......

$query = $this->db->select('suppliers.*, category.strCategory, category_1.strCategory AS strParent, tblcitylist.city_name')
            ->from('suppliers')
            ->join('category',                  'suppliers.intCat=Category.intId',          'inner')
            ->join('tblcitylist',               'suppliers.intCity=tblcitylist.city_id',    'inner')
            ->join('category as `category_1',   'category.intParent=Category_1.intId',      'left')
            ->where('status','y')
                ->get();

CI 数据库文档:https://www.codeigniter.com/user_guide/database/index.html