def METHOD_NAME(self):
    seen_on_days_clause = "\nUNION ALL\n".join(
        period_query.get_query() for period_query in self.major_period_queries
    )
    sql = f"""
    SELECT subscriber
    FROM ({seen_on_days_clause}) AS tbl
    GROUP BY subscriber
    HAVING count(subscriber) >= {self.major_period_threshold}
    """
    return sql