Codeigniter內部聯接不起作用

Question

我想與Codeigniter進行內部連接，我嘗試了很多，但沒有成功。

用於內部聯接的MySQL代碼，

SELECT * FROM shop INNER JOIN city ON city.city_id = shop.city_id WHERE city.city_name = 'Bangalore'

上面的sql查詢在phpmyadmin中運行正常。 在codeigniter中轉換此代碼時，它不起作用。

Codeigniter代碼是，

$this->db->select('*');
$this->db->from('shop');
$this->db->join('city', 'city.city_id = shop.city_id');
$query = $this->db->where('city', array('city.city_name' => 'Bangalore'));

if($query->num_rows() > 0) {
    return $result = $query->result_array();
}
else {
    return 0;
}

哪里出了問題。 是codeigniter的初學者。

Answer 1

您的查詢應該運作良好：

$this->db->select('*');
$this->db->from('shop');
$this->db->join('city', 'city.city_id = shop.city_id');
//$this->db->where('city', array('city.city_name' => 'Bangalore'));
$this->db->where('city.city_name', 'Bangalore');
$query = $this->db->get();

Answer 2

嘗試這個：

$query = $this->db->select('*')
          ->from('shop')
          ->join('city', 'city.city_id = shop.city_id', 'inner')
          ->where('city.city_name', 'Bangalore');
          ->get();

Answer 3

您錯過了從db get()數據的機會，

更改為

$query = $this->db->where('city', array('city.city_name' => 'Bangalore'));

這個

$this->db->where('city', array('city.city_name' => 'Bangalore'));
$query = $this->db->get();// add this line.

不需要from()您可以使用get()並將表名傳遞給它，就像這樣。

$this->db->select('*');
//$this->db->from('shop');   <-- no need of this line
$this->db->join('city', 'city.city_id = shop.city_id');
$this->db->where('city', array('city.city_name' => 'Bangalore'));
$query = $this->db->get("shop");//<-- give table name here only.