'Quering data into a DataFrame.
:param chunked: [Optional, default=False] True if the data shall be
retrieved in chunks, False otherwise.'

def query(self, query, chunked=False, database=None):

    results = super(DataFrameClient, self).query(query, database=database)
    if query.strip().upper().startswith(u'SELECT'):
        if (len(results) > 0):
            return self._to_dataframe(results)
        else:
            return {}
    else:
        return results
