/**
         * Tell the ORM that you are expecting multiple results
         * from your query, and execute it. Will return an array
         * of instances of the ORM class, or an empty array if
         * no rows were returned.
         * @return array
         */
        protected function _find_many() {
            $rows = $this->_run();
            return $this->_instances_with_keys($rows);
        }

        /**
         * Map the rows in keys equal to the id column, instead of no information ones
         */
        protected function _instances_with_keys($rows){
            $size = count($rows);
            $instances = array();
            for ($i = 0; $i < $size; $i++) {
                $row = $this->_create_instance_from_row($rows[$i]);
                $key = (isset($row->{$this->_instance_id_column})) ? $row->{$this->_instance_id_column} : $i;
                $instances[$key] = $row;
            }

            return $instances;
        }