Codeigniter this->db->query unidentified index - php

Question

I am trying to execute the following query using CodeIgniter, but I am getting
Unidentified index for ->row['code'];
public function getSExtension($id) {
$temp = array();
$query = $this->db->query("SELECT extension_id FROM " . DB_PREFIX . "zipcode_shipping WHERE `zip_code` = '" . $id . "'");
if($query->num_rows) {
foreach ($query->rows as $key => $value) {
$code = $this->db->query("SELECT code FROM " . DB_PREFIX . "extension WHERE `extension_id` = '" . $value['extension_id'] . "'")->row['code'];
$this->language->load("shipping/".$code);
$temp[] = $this->language->get('text_title');
}
}
return $temp;
}

Answer 1

The problem is you have not correctly retrieved a result set which requires a method call. As you have it you are trying to use db properties that don't exist i.e. $query->rows should probably be $query->row_array().
Documentation Here.
In the example below I use result() and row() instead of any "array" methods.
Try this.
$temp = array();
$query = $this->db->query("SELECT extension_id FROM ".DB_PREFIX."zipcode_shipping WHERE `zip_code` = '".$id."'");
if($query->num_rows() > 0)
{
foreach($query->result() as $value)
{
$code = $this->db->query("SELECT code FROM ".DB_PREFIX."extension WHERE `extension_id` = '".$value->extension_id."'")->row()->code;
$this->language->load("shipping/".$code);
$temp[] = $this->language->get('text_title');
}
}