public function ajax_relation($state_info)
 {
     if (!isset($this->relation[$state_info->field_name])) {
         return false;
     }
     list($field_name, $related_table, $related_field_title, $where_clause, $order_by) = $this->relation[$state_info->field_name];
     return $this->basic_model->get_ajax_relation_array($state_info->search, $field_name, $related_table, $related_field_title, $where_clause, $order_by);
 }