笨加入3個表，並從第一個表，其中1臺與第2臺和第二臺聯的數據與3臺聯

Question

user_table(user_id, user_name) 

user_group_table(user_id, group_id) 

group_table(group_id, group_name) 

我需要檢索數據(user_id, user_name, group_name)

我怎樣才能加入笨這些表？

Answer 1

$this->db->query('SELECT user_table.user_id, user_table.user_name, 
        group_table.group_name 
        FROM 
        user_table 
        join user_group_table on user_group_table.user_id=user_table.user_id 
        join group_table on group_table.group_id=user_group_table.group_id') 
        ->result_array(); 

回報，並打印/使用數組，只要你喜歡或者你可以用笨Query Builder類

Answer 2

$where = array(); //if u want to use any condition 
$this->db->select('user_table.user_id, user_table.user_name, group_table.group_name'); 
$this->db->join('user_group_table', 'user_group_table.user_id = user_table.user_id'); 
$this->db->join('group_table', 'group_table.group_id = user_group_table.group_id'); 
$result = $this->db->order_by('user_table.user_id', 'desc')->get_where('property', $where)->result_array(); 
return $result 

Answer 3

$this->db->select('user_table.user_id,user_table.user_name,group_table.group_name'); 
$this->db->from('user_group_table'); 
$this->db->join('user_table', 'user_table.user_id = user_group_table.user_id'); 
$this->db->join('group_table', 'group_table.group_id = user_group_table.group_id'); 
$query = $this->db->get(); 
$res = $query->result(); 
return $res;