如何從類別ID使用codeigniter得到結果的父類名稱

Question

請幫助我，如何獲取類別的父母名稱。我有這樣的桌子。

table Category 
+-------------+-----------------+-----------------+---------------+ 
| category_id | category_name | category_parent | category_slug | 
+-------------+-----------------+-----------------+---------------+ 
|   7 | Framework CSS |    0 |    | 
|   9 | Bootstrap  |    7 |    | 
|   10 | Material Design |    7 |    | 
+-------------+-----------------+-----------------+---------------+ 

table relationship 
+-----------------+---------+-------------+ 
| relationship_id | post_id | category_id | 
+-----------------+---------+-------------+ 
|    35 |  59 |   9 | 
+-----------------+---------+-------------+ 

我使用codeigniter，我有一個函數來獲取帖子和類別。

public function post_detail($tableName, $where = '') 
{ 
    $post_title = $this->uri->segment(3); 

    $query = $this->db->query("SELECT p.*, r.*, c.* FROM tbl_relationship AS r 
     INNER JOIN tbl_posts AS p ON r.post_id = p.post_id 
     INNER JOIN tbl_category AS c ON r.category_id = c.category_id 
     WHERE p.post_name = '$post_title' 
    "); 
    return $query->result();  
} 

函數結果：（7和bootstrap）。如何產生7.的父母名稱？

Answer 1

試試這個：

public function post_detail($tableName, $where = '') 
{ 
    $post_title = $this->uri->segment(3); 

    $query = $this->db->query("SELECT p.*, r.*, c.*, c1.category_name as parent_name FROM tbl_relationship AS r 
     INNER JOIN tbl_posts AS p ON r.post_id = p.post_id 
     INNER JOIN tbl_category AS c ON r.category_id = c.category_id 
     INNER JOIN tbl_category AS c1 ON c.category_parent = c1.category_id 
     WHERE p.post_name = '$post_title' 
    "); 
    return $query->result();  
}