def database(self, database_id, ddl_statements=(), pool=None):
        """Factory to create a database within this instance.

        :type database_id: str
        :param database_id: The ID of the instance.

        :type ddl_statements: list of string
        :param ddl_statements: (Optional) DDL statements, excluding the
                               'CREATE DATABSE' statement.

        :type pool: concrete subclass of
                    :class:`~google.cloud.spanner_v1.pool.AbstractSessionPool`.
        :param pool: (Optional) session pool to be used by database.

        :rtype: :class:`~google.cloud.spanner_v1.database.Database`
        :returns: a database owned by this instance.
        """
        return Database(database_id, self, ddl_statements=ddl_statements, pool=pool)
Factory to create a database within this instance.

        :type database_id: str
        :param database_id: The ID of the instance.

        :type ddl_statements: list of string
        :param ddl_statements: (Optional) DDL statements, excluding the
                               'CREATE DATABSE' statement.

        :type pool: concrete subclass of
                    :class:`~google.cloud.spanner_v1.pool.AbstractSessionPool`.
        :param pool: (Optional) session pool to be used by database.

        :rtype: :class:`~google.cloud.spanner_v1.database.Database`
        :returns: a database owned by this instance.