我有以下表格:笨SQL查询中的连接上两个不同的列
用户:
+----+-------+-------+
| ID | fname | lname |
+----+-------+-------+
| 1 | Joe | Doe |
+----+-------+-------+
| 2 | Jane | Doet |
+----+-------+-------+
产品:
+----+------+------------+------------+
| ID | name | created_by | updated_by | //created_by and updated_by are user Ids
+----+------+------------+------------+
| 1 | some | 1 | 1 |
+----+------+------------+------------+
| 2 | some | 1 | 2 |
+----+------+------------+------------+
| 3 | some | 2 | 2 |
+----+------+------------+------------+
| 4 | some | 2 | 1 |
+----+------+------------+------------+
我想创建一个查询,它输出以下表:
+--------------+------------+------------+
| Product Name | Created By | Updated By |
+--------------+------------+------------+
| Some | Jane Doet | Joe Doe |
+--------------+------------+------------+
到目前为止,我使用Join
这样:
public function getAll() {
$this->db->select('products.* , users.fname, users.lname');
$this->db->from('products');
$this->db->join('users', 'users.id = products.updated_by', 'left');
$q = $this->db->get();
return $q->result();
}
将会产生如下:
SELECT products.*, users.fname, users.lname
FROM `products`
LEFT JOIN users ON users.id=products.updated_by
这工作,并得到了我的updated_by
用户信息,但如果我想无论是created
和updated
用户信息,我如何进行该查询?
再添加一个加入连接'created_by' –
你能告诉我如何? – CodeGodie