Checks if an index begins in the order of the given columns.

        :type columns: list

        :rtype: bool

def columns_are_indexed(self, columns):
        """
        Checks if an index begins in the order of the given columns.

        :type columns: list

        :rtype: bool
        """
        for index in self._indexes.values():
            if index.spans_columns(columns):
                return True

        return False