将模型对象ID从模型复制到Django中的另一个模型

Question

我想将数据从一个模型复制到另一个模型，我在Django中找到了一个将模型对象从一个模型复制到另一个模型的示例，但出现错误：

AttributeError：'BigAutoField'对象没有属性'wid'。

我想wid的tobjects模型来获得Id从w_orders模型。 这是我的代码：

models.py

class w_orders(models.Model): 
    Id = models.BigAutoField(primary_key=True)
    datedefwo = models.DateField(default=datetime.now)
    datesched = models.DateField(blank=True, null=True)
    datefinished = models.DateField(blank=True, null=True)
    sign = models.BigIntegerField(blank=True, null=True)
    statusid = models.BigIntegerField(blank=True, null=True, default=1, choices=STATUS_CHOICES)
    typeid = models.BigIntegerField(blank=True, null=True, default=1, choices=TYPE_CHOICES)
    comments = models.CharField(max_length=254, blank=True, null=True)
    navid = models.BigIntegerField(blank=True, null=True)
    navkonsid = models.CharField(max_length=12, blank=True, null=True)
    navname = models.CharField(max_length=254, blank=True, null=True)
    navcustadr = models.CharField(max_length=254, blank=True, null=True)
    navdebt = models.FloatField(blank=True, null=True)
    navpropcode = models.CharField(max_length=254, blank=True, null=True)
    navdepcode = models.CharField(max_length=254, blank=True, null=True)
    navphoneno = models.CharField(max_length=254, blank=True, null=True)
    navreasoncomp = models.CharField(max_length=254, blank=True, null=True)
    nightshift = models.BooleanField(default=False)
    priority = models.BigIntegerField(blank=True, null=True)
    stid = models.BigIntegerField(blank=True, null=True)
    mapurl = models.CharField(max_length=254, blank=True, null=True)

    def __unicode__(self):
        return self.Id

    def save(self, *args, **kwargs):
        super(w_orders, self).save(*args, **kwargs)
        newob = tobjects()
        ...
        newob.save()



class tobjects(models.Model): 
    oid = models.BigAutoField(primary_key=True)
    wid = models.ForeignKey(w_orders, on_delete=models.CASCADE)
    objtypegisid = models.BigIntegerField(blank=True, null=True, default=1)
    objgisid = models.BigIntegerField(blank=True, null=True, default=1)
    condgenid = models.BigIntegerField(blank=True, null=True, default=1)
    condriskid = models.BigIntegerField(blank=True, null=True, default=1)
    condratsid = models.BigIntegerField(blank=True, null=True, default=1)
    condmhcoverid = models.BigIntegerField(blank=True, null=True, default=1)
    condmhwallid = models.BigIntegerField(blank=True, null=True, default=1)
    condpipehydrsid = models.BigIntegerField(blank=True, null=True, default=1)
    condpipehydreid = models.BigIntegerField(blank=True, null=True, default=1)
    condpipedepvolsid = models.BigIntegerField(blank=True, null=True, default=1)
    condpipedepvoleid = models.BigIntegerField(blank=True, null=True, default=1)
    condpipedepconssid = models.BigIntegerField(blank=True, null=True, default=1)
    condpipedepconseid = models.BigIntegerField(blank=True, null=True, default=1)
    txt = models.CharField(max_length=254, blank=True, null=True)

    def __unicode__(self):
        return self.oid

Answer 1

class w_orders(models.Model): 
    Id = models.BigAutoField(primary_key=True)
    datedefwo = models.DateField(default=datetime.now)
    datesched = models.DateField(blank=True, null=True)
    datefinished = models.DateField(blank=True, null=True)
    sign = models.BigIntegerField(blank=True, null=True)
    statusid = models.BigIntegerField(blank=True, null=True, default=1, choices=STATUS_CHOICES)
    typeid = models.BigIntegerField(blank=True, null=True, default=1, choices=TYPE_CHOICES)
    comments = models.CharField(max_length=254, blank=True, null=True)
    navid = models.BigIntegerField(blank=True, null=True)
    navkonsid = models.CharField(max_length=12, blank=True, null=True)
    navname = models.CharField(max_length=254, blank=True, null=True)
    navcustadr = models.CharField(max_length=254, blank=True, null=True)
    navdebt = models.FloatField(blank=True, null=True)
    navpropcode = models.CharField(max_length=254, blank=True, null=True)
    navdepcode = models.CharField(max_length=254, blank=True, null=True)
    navphoneno = models.CharField(max_length=254, blank=True, null=True)
    navreasoncomp = models.CharField(max_length=254, blank=True, null=True)
    nightshift = models.BooleanField(default=False)
    priority = models.BigIntegerField(blank=True, null=True)
    stid = models.BigIntegerField(blank=True, null=True)
    mapurl = models.CharField(max_length=254, blank=True, null=True)

    def __unicode__(self):
        return self.Id




class tobjects(models.Model): 
    oid = models.BigAutoField(primary_key=True)
    wid = models.ForeignKey(w_orders, on_delete=models.CASCADE)
    objtypegisid = models.BigIntegerField(blank=True, null=True, default=1)
    objgisid = models.BigIntegerField(blank=True, null=True, default=1)
    condgenid = models.BigIntegerField(blank=True, null=True, default=1)
    condriskid = models.BigIntegerField(blank=True, null=True, default=1)
    condratsid = models.BigIntegerField(blank=True, null=True, default=1)
    condmhcoverid = models.BigIntegerField(blank=True, null=True, default=1)
    condmhwallid = models.BigIntegerField(blank=True, null=True, default=1)
    condpipehydrsid = models.BigIntegerField(blank=True, null=True, default=1)
    condpipehydreid = models.BigIntegerField(blank=True, null=True, default=1)
    condpipedepvolsid = models.BigIntegerField(blank=True, null=True, default=1)
    condpipedepvoleid = models.BigIntegerField(blank=True, null=True, default=1)
    condpipedepconssid = models.BigIntegerField(blank=True, null=True, default=1)
    condpipedepconseid = models.BigIntegerField(blank=True, null=True, default=1)
    txt = models.CharField(max_length=254, blank=True, null=True)

    def __unicode__(self):
        return self.oid

    @receiver(post_save, sender=w_orders)
    def ensure_order_exists(sender, **kwargs):
        if kwargs.get('created', False):
            tobjects.objects.get_or_create(wid=kwargs.get('instance'))

Answer 2

for o in w_orders.objects.all():
    t = tobjects.create(wid=o)
    t.save()

也可以使用bulk_create，它速度更快，但仅适用于PostgreSQL（请阅读https://docs.djangoproject.com/en/dev/ref/models/querysets/#bulk-create ）：

tobjects.objects.bulk_create([tobjects(wid=o) for o in w_orders.objects.all()])

请考虑使用PEP 8作为您的代码。 太可怕了。