def __message(expected_row_count, actual_row_count, query):
        """
        Composes the exception message.

        :param str expected_row_count: The expected row count.
        :param int actual_row_count: The actual row count.
        :param str query: The query.

        :rtype: str
        """
        query = query.strip()

        message = 'Wrong number of rows selected'
        message += os.linesep
        message += 'Expected number of rows: {}'.format(expected_row_count)
        message += os.linesep
        message += 'Actual number of rows: {}'.format(actual_row_count)
        message += os.linesep
        message += 'Query:'
        message += os.linesep if os.linesep in query else ' '
        message += query

        return message
Composes the exception message.

        :param str expected_row_count: The expected row count.
        :param int actual_row_count: The actual row count.
        :param str query: The query.

        :rtype: str