public function beforeUpdate(array &$args) {
        $data = &$args[1];
        foreach ($data as $key => $value) {
            /**
             * Save the current file value.
             * If it differs from the given value, it will be cleared
             * by afterUpdate.
             */
            if (in_array($key, $this->_fields)) {
                $this->_newValues[$key] = $value;
                if (!$this->_affectedRows) {
                    $model = $args[0];
                    $where = $args[2];
                    $affectedRows = $model->fetchAll($where);
                    $this->_affectedRows = $affectedRows;
                }
            }
        }
    }