Returns a list of tables [schema1.table1, schema2.table2, ...]

        Datasource_type can be 'table' or 'view'.
        Empty schema corresponds to the list of full names of the all
        tables or views: <schema>.<result_set_name>.

def fetch_result_sets(cls, db, datasource_type):
        """Returns a list of tables [schema1.table1, schema2.table2, ...]

        Datasource_type can be 'table' or 'view'.
        Empty schema corresponds to the list of full names of the all
        tables or views: <schema>.<result_set_name>.
        """
        result_set_df = db.get_df(
            """SELECT table_schema, table_name FROM INFORMATION_SCHEMA.{}S
               ORDER BY concat(table_schema, '.', table_name)""".format(
                datasource_type.upper(),
            ),
            None)
        result_sets = []
        for unused, row in result_set_df.iterrows():
            result_sets.append('{}.{}'.format(
                row['table_schema'], row['table_name']))
        return result_sets