关于python：创建一个新模型，其中包含当前现有模型的所有字段

Create a new model which have all fields of currently existing model

我正在用我的django应用程序制作一个模型Player。

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class Player(models.Model):
""" player model"""
name = models.CharField(max_length=100, null=True, blank=True)
date_created = models.DateTimeField(auto_now_add=True)
last_updated = models.DateTimeField(auto_now=True)
hash = models.CharField(max_length=128, null=True, blank=True)
bookmark_url = models.CharField(max_length=300, null=True, blank=True)

根据我的要求，我需要创建一个新的模型BookmarkPlayer，它将具有Player模型的所有字段。

现在我有两件事要做。

我可以为bookmarkplayer模型扩展player类。

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class BookmarkPlayer(Player):
""" just a bookmark player"""
class Meta:
app_label ="core"

我可以将播放器模型的所有字段定义为bookmarkplayer模型。

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class BookmarkPlayer(models.Model):
""" bookmark player model"""
name = models.CharField(max_length=100, null=True, blank=True)
date_created = models.DateTimeField(auto_now_add=True)
last_updated = models.DateTimeField(auto_now=True)
hash = models.CharField(max_length=128, null=True, blank=True)
bookmark_url = models.CharField(max_length=300, null=True, blank=True)

我只想知道哪种方法更好。如果还有别的好方法，请和我分享。

更新的问题

Knbb创建基类的想法很有趣，但我面临的问题是我的一个模型已经存在于数据库中。

我的实际型号：

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class Address(models.Model):
address = models.TextField(null=True, blank=True)

class Site(models.Model):
domain = models.CharField(max_length=200)

class Player(models.Model):
# ... other fields
shipping_address = models.ForeignKey(Address, related_name='shipping')
billing_address = models.ForeignKey(Address, related_name='billing')
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now_add=True)
site = models.ManyToManyField(Site, null=True, blank=True)

class Meta:
abstract = True

更改后的模型：

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class Address(models.Model):
address = models.TextField(null=True, blank=True)

class Site(models.Model):
domain = models.CharField(max_length=200)

class BasePlayer(models.Model):
# .. other fields
shipping_address = models.ForeignKey(Address, related_name='shipping')
billing_address = models.ForeignKey(Address, related_name='billing')
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now_add=True)
site = models.ManyToManyField(Site, null=True, blank=True)

class Meta:
abstract = True

class Player(BasePlayer):
class Meta:
app_label = 'core'

class BookmarkPlayer(BasePlayer):
class Meta:
app_label = 'core'

在这些更改之后，当我运行Django服务器时，我会收到下面给出的错误。

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django.core.management.base.CommandError: One or more models did not validate:
core.test1: Accessor for field 'shipping_address' clashes with related field 'Address.shipping'. Add a related_name argument to the definition for 'shipping_address'.
core.test1: Reverse query name for field 'shipping_address' clashes with related field 'Address.shipping'. Add a related_name argument to the definition for 'shipping_address'.
core.test1: Accessor for field 'billing_address' clashes with related field 'Address.billing'. Add a related_name argument to the definition for 'billing_address'.
core.test1: Reverse query name for field 'billing_address' clashes with related field 'Address.billing'. Add a related_name argument to the definition for 'billing_address'.
core.test2: Accessor for field 'shipping_address' clashes with related field 'Address.shipping'. Add a related_name argument to the definition for 'shipping_address'.
core.test2: Reverse query name for field 'shipping_address' clashes with related field 'Address.shipping'. Add a related_name argument to the definition for 'shipping_address'.
core.test2: Accessor for field 'billing_address' clashes with related field 'Address.billing'. Add a related_name argument to the definition for 'billing_address'.
core.test2: Reverse query name for field 'billing_address' clashes with related field 'Address.billing'. Add a related_name argument to the definition for 'billing_address'

答：最后，如果我们将foreignkey或manytomanyfield上的相关_name属性用于抽象模型，我得到了答案。这通常会在抽象基类中引起问题，因为这个类上的字段包含在每个子类中，每次属性(包括相关的名称)的值都完全相同。为了解决这个问题，在抽象基类中使用相关的_名称(仅限)时，名称的一部分应包含"%"(app_label)s'和"%"(class)s'。https://docs.djangoproject.com/en/dev/topics/db/models/抽象基类现在我的棒球手模型是

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class BasePlayer(models.Model):
# .. other fields
shipping_address = models.ForeignKey(Address, related_name='%(app_label)s_%(class)s_shipping')
billing_address = models.ForeignKey(Address, related_name='%(app_label)s_%(class)s_billing')
created_at = models.DateTimeField(auto_now_add=True)
updated_at = models.DateTimeField(auto_now_add=True)
site = models.ManyToManyField(Site, null=True, blank=True)

class Meta:
abstract = True