airflow/contrib/hooks/bigquery_hook.py
def _bq_cast(string_field, bq_type):
    """
    Helper method that casts a BigQuery row to the appropriate data types.
    This is useful because BigQuery returns all fields as strings.
    """
    if string_field is None:
        return None
    elif bq_type == 'INTEGER':
        return int(string_field)
    elif bq_type == 'FLOAT' or bq_type == 'TIMESTAMP':
        return float(string_field)
    elif bq_type == 'BOOLEAN':
        if string_field not in ['true', 'false']:
            raise ValueError("{} must have value 'true' or 'false'".format(
                string_field))
        return string_field == 'true'
    else:
        return string_field
def _bq_cast(string_field, bq_type):
    """
    Helper method that casts a BigQuery row to the appropriate data types.
    This is useful because BigQuery returns all fields as strings.
    """
    if string_field is None:
        return None
    elif bq_type == 'INTEGER':
        return int(string_field)
    elif bq_type == 'FLOAT' or bq_type == 'TIMESTAMP':
        return float(string_field)
    elif bq_type == 'BOOLEAN':
        if string_field not in ['true', 'false']:
            raise ValueError("{} must have value 'true' or 'false'".format(
                string_field))
        return string_field == 'true'
    else:
        return string_field
Helper method that casts a BigQuery row to the appropriate data types.
    This is useful because BigQuery returns all fields as strings.