BigQuery supports clustering for both partitioned and non-partitioned tables.

Reference: [https://cloud.google.com/bigquery/docs/clustered-tables](https://cloud.google.com/bigquery/docs/clustered-tables)
airflow/providers/google/cloud/transfers/gcs_to_bigquery.py
"""
    Loads files from Google Cloud Storage into BigQuery.
    The schema to be used for the BigQuery table may be specified in one of
    two ways. You may either directly pass the schema fields in, or you may
    point the operator to a Google Cloud Storage object name. The object in
    Google Cloud Storage must be a JSON file with the schema fields in it.
    .. seealso::
        For more information on how to use this operator, take a look at the guide:
        :ref:`howto/operator:GCSToBigQueryOperator`
    :param bucket: The bucket to load from. (templated)
    :type bucket: str
    :param source_objects: List of Google Cloud Storage URIs to load from. (templated)
        If source_format is 'DATASTORE_BACKUP', the list must only contain a single URI.
    :type source_objects: list[str]
    :param destination_project_dataset_table: The dotted
        ``(<project>.|<project>:)<dataset>.<table>`` BigQuery table to load data into.
        If ``<project>`` is not included, project will be the project defined in
        the connection json. (templated)
    :type destination_project_dataset_table: str
    :param schema_fields: If set, the schema field list as defined here:
        https://cloud.google.com/bigquery/docs/reference/v2/jobs#configuration.load
        Should not be set when source_format is 'DATASTORE_BACKUP'.
        Parameter must be defined if 'schema_object' is null and autodetect is False.
    :type schema_fields: list
    :param schema_object: If set, a GCS object path pointing to a .json file that
        contains the schema for the table. (templated)
        Parameter must be defined if 'schema_fields' is null and autodetect is False.
    :type schema_object: str
    :param source_format: File format to export.