public function handleUpdateAttribute(PostPersistModelEvent $event)
    {
        $model = $event->getModel();

        if (('file' !== $model->getProperty('type'))
            || (!$model->getProperty('file_multiple'))
            || ('tl_metamodel_attribute' !== $event->getEnvironment()->getDataDefinition()->getName())
        ) {
            return;
        }

        $metaModelsName = $this->getFactory()->translateIdToMetaModelName($model->getProperty('pid'));
        $metaModel      = $this->getFactory()->getMetaModel($metaModelsName);
        $attributeName  = $model->getProperty('colname') . '__sort';
        $tableColumns   = $this->connection->getSchemaManager()->listTableColumns($metaModel->getTableName());

        if (\array_key_exists($attributeName, $tableColumns)) {
            return;
        }

        $this->tableManipulator->createColumn($metaModel->getTableName(), $attributeName, 'blob NULL');
    }