protected function doUpdateObjects(Sport $model, $data) {
		// remove all relationships before
		ObjectQuery::create()->filterBySport($model)->delete();

		// add them
		$errors = [];
		foreach ($data as $entry) {
			if (!isset($entry['id'])) {
				$errors[] = 'Missing id for Object';
			} else {
				$related = ObjectQuery::create()->findOneById($entry['id']);
				$model->addObject($related);
			}
		}

		if (count($errors) > 0) {
			throw new ErrorsException($errors);
		}
	}