使用 Codeigniter 进行复杂查询连接

Question

我有一个查询在 phpmyadmin 中产生结果，但在 codeigniter 中没有。

$sql = "SELECT express_interests.*, 
       cl_to  .User_Name AS ToClient, 
       cl_from.User_Name AS FromClient,
       cl_from.Member_Id AS FromMid,
       cl_to.Member_Id AS ToMid

FROM express_interests  
    INNER JOIN users AS cl_to ON cl_to.User_Id = express_interests.To_Id
    INNER JOIN users AS cl_from ON cl_from.User_Id = express_interests.User_Id";

我想在 codeignitor 中使用相同的查询。这是我用过的

$this->db->select('express_interests.*, 
       cl_to  .User_Name AS ToClient, 
       cl_from.User_Name AS FromClient,
       cl_from.Member_Id AS FromMid,
       cl_to.Member_Id AS ToMid
');

$this->db->from('express_interests');


$this->db->join('users AS cl_to', 'cl_to.User_Id = express_interests.To_Id');
$this->db->join('users AS cl_from', 'cl_from.User_Id = express_interests.User_Id');

当我使用它时它说

Unknown column 'cl_to .User_Name' in 'field list'

在 codeigniter 中使用上述查询的正确方法是什么。

Answer 1

$this->db->select('express_interests.*, 
       cl_to  .User_Name AS ToClient, 
       cl_from.User_Name AS FromClient,
       cl_from.Member_Id AS FromMid,
       cl_to.Member_Id AS ToMid
');

将其替换为

$this->db->select('express_interests.*, 
       cl_to.User_Name AS ToClient, 
       cl_from.User_Name AS FromClient,
       cl_from.Member_Id AS FromMid,
       cl_to.Member_Id AS ToMid
');

table 别名和列名之间不需要的间距

Answer 2

替换

cl_to  .User_Name AS ToClient,

与

cl_to.User_Name AS ToClient,

或者你可以在codeigniter中直接运行 sql声明为

$sql = "SELECT express_interests.*, 
   cl_to.User_Name AS ToClient,
   cl_from.User_Name AS FromClient,
   cl_from.Member_Id AS FromMid,
   cl_to.Member_Id AS ToMid

FROM express_interests  
INNER JOIN users AS cl_to ON cl_to.User_Id = express_interests.To_Id
INNER JOIN users AS cl_from ON cl_from.User_Id = express_interests.User_Id"; 

$result=$this->db->query($sql);

print_r($result->result());

die;

使用 Codeigniter 进行复杂查询连接

Complex query join using Codeigniter

php

mysql

codeigniter

codeigniter-2

codeigniter-3