Django 数据库模型 一对多、多对多问题疑惑

一个域名监控

思路如下

域名 -> IP -> IP 段

但是 IP 与 IP 段都分别有 v4 与 v6 的 且域名可能同时拥有 v4 与 v6 的 IP

想了半天也不知道怎么去设计

看了很多 Django 的多对多(ManyToManyField) 的文章也弄不懂

如下代码 Domain 类里面的属性 ip 是不是应该用多对多的方式

方法一的代码是不是不应该这样子写的

方法一

class IPv4Range(models.Model):
    ipv4_range = models.CharField(max_length=20)
    last_update = models.DateTimeField(auto_now_add=True)


class IPv6Range(models.Model):
    ipv6_range = models.CharField(max_length=40)
    last_update = models.DateTimeField(auto_now_add=True)


class IPv4Address(models.Model):
    iprange = models.ForeignKey('IPv4Range', on_delete=models.PROTECT)
    ipv4 = models.CharField(max_length=20)
    last_update = models.DateTimeField(auto_now_add=True)
    

class IPv6Address(models.Model):
    iprange = models.ForeignKey('IPv6Range', on_delete=models.PROTECT)
    ipv6 = models.CharField(max_length=40)
    last_update = models.DateTimeField(auto_now_add=True)
    

class Domain(models.Model):
    ip = models.ForeignKey(IPv4Address, on_delete=models.PROTECT)
    domain = models.CharField(max_length=255)
    checked = models.BooleanField(default=False)
    keyword = models.CharField(max_length=255)
    add_date = models.DateTimeField(auto_now_add=True)
    last_update = models.DateTimeField(auto_now=True)

方法二

class IPRange(models.Model):
    ipv4_range = models.CharField(max_length=20, null=True)
    ipv6_range = models.CharField(max_length=40, null=True)
    last_update = models.DateTimeField(auto_now_add=True)



class IPAddress(models.Model):
    iprange = models.ForeignKey('IPRange', on_delete=models.PROTECT)
    ipv4 = models.CharField(max_length=20, null=True)
    ipv6 = models.CharField(max_length=40, null=True)
    last_update = models.DateTimeField(auto_now_add=True)
    


class Domain(models.Model):
    ip = models.ForeignKey(IPAddress, on_delete=models.PROTECT)
    domain = models.CharField(max_length=255)
    checked = models.BooleanField(default=False)
    keyword = models.CharField(max_length=255)
    add_date = models.DateTimeField(auto_now_add=True)
    last_update = models.DateTimeField(auto_now=True)