blocks|key|1672551|text|您不能与抽象模型建立关系，但这就是您要做的事情(ManyToManyField到OtherModel)。如果您想使此工作，您需要删除abstract+=+True从OtherModel和添加common到您的INSTALLED_APPS！|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1672552|如果您想要从OtherModel的子类中关联到Base的不同子类，则需要在子类上定义关系，而不是在抽象模型上！|1672553|entityMap^0|O|F|14|A|1U|F|2A|A|2N|6|2W|E|0|6|A|N|4|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]|$9|M|A|N|B|C]|$9|O|A|P|B|C]|$9|Q|A|R|B|C]|$9|S|A|T|B|C]|$9|U|A|V|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|W|8|@$9|X|A|Y|B|C]|$9|Z|A|10|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|11|8|@]|D|@]|E|$]]]|I|$]]

You cannot have a relation with an abstract model, but this is what you are trying to do (<code>ManyToManyField</code> to <code>OtherModel</code>). If you want to make this work you need to remove <code>abstract = True</code> from <code>OtherModel</code> and add <code>common</code> to your <code>INSTALLED_APPS</code>! 

If you want to relate to different sublasses of <code>OtherModel</code> from the subclasses of <code>Base</code> you will need to define the relation on the subclass, not on the abstract model!

blocks|key|1672570|text|我发现了问题.|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1672571|--这是可行的：|offset|length|style|BOLD|1672572|from+django.db+import+models

class+CommonInfo(models.Model):

++++name+=+models.CharField(max_length=100)

class+Base(models.Model):
++++m2m+=+models.ForeignKey(CommonInfo,+related_name="%25(app_label)s_%25(class)s_related")

++++class+Meta:
++++++++abstract+=+True

class+ChildA(Base):
++++pass|code-block|syntax|javascript|1672573|--这将给您一个错误:+AssertionError:+ForeignKey不能定义带有抽象类OtherModel.This的关系，因为不能在指向另一个抽象类的抽象类上有FK关系或M2M关系。|1672574|from+django.db+import+models

class+CommonInfo(models.Model):
++++class+Meta:
++++++++abstract+=+True

++++name+=+models.CharField(max_length=100)

class+Base(models.Model):
++++m2m+=+models.ForeignKey(CommonInfo,+related_name="%25(app_label)s_%25(class)s_related")

++++class+Meta:
++++++++abstract+=+True

class+ChildA(Base):
++++pass|1672575|这对我来说是个不幸的消息。真是个不幸的消息。我希望我的坏消息能让别人受益。|1672576|entityMap^0|0|0|8|0|0|0|1L|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@$D|W|E|X|F|G]]|9|@]|A|$]]|$1|H|3|I|5|J|7|Y|8|@]|9|@]|A|$K|L]]|$1|M|3|N|5|6|7|Z|8|@$D|10|E|11|F|G]]|9|@]|A|$]]|$1|O|3|P|5|J|7|12|8|@]|9|@]|A|$K|L]]|$1|Q|3|R|5|6|7|13|8|@]|9|@]|A|$]]|$1|S|3|-4|5|6|7|14|8|@]|9|@]|A|$]]]|T|$]]

I figured out the problem..... 

This will work:

<pre><code>from django.db import models

class CommonInfo(models.Model):

 name = models.CharField(max_length=100)

class Base(models.Model):
 m2m = models.ForeignKey(CommonInfo, related_name="%(app_label)s_%(class)s_related")

 class Meta:
 abstract = True

class ChildA(Base):
 pass
</code></pre>

This will give you the error: AssertionError: ForeignKey cannot define a relation with abstract class OtherModel.This is because you can't have a FK relationship or M2M relationship on an abstract pointing to ANOTHER abstract class. 

<pre><code>from django.db import models

class CommonInfo(models.Model):
 class Meta:
 abstract = True

 name = models.CharField(max_length=100)

class Base(models.Model):
 m2m = models.ForeignKey(CommonInfo, related_name="%(app_label)s_%(class)s_related")

 class Meta:
 abstract = True

class ChildA(Base):
 pass
</code></pre>

This is sad news for me. Sad news indeed. I hope my sad news benefits someone else.

I dam trying to do this: 
<a href="http://docs.djangoproject.com/en/dev/topics/db/models/#be-careful-with-related-name" rel="nofollow">http://docs.djangoproject.com/en/dev/topics/db/models/#be-careful-with-related-name</a>

Using this style

This is saved as common/abstract.py

<pre><code>class OtherModel(models.Model):

 something = Charfield(max_length=100)

 class Meta:
 abstract = True

class Base(models.Model):
 fk_model = models.ForeignKey(OtherModel, related_name="%(app_label)s_%(class)s_related")

 class Meta:
 abstract = True
</code></pre>

Then I import it into another file. Let's call this app/models.py

<pre><code>from common.abstract import Base

class ChildB(Base):
 pass
</code></pre>

I have installed 'app' but not the 'common'. It will import nicely without the FK or M2M relationship, but when I try to add it, I get this error: 

/lib/python2.6/site-packages/django/db/models/fields/related.py", line 808, in init
 assert not to.meta.abstract, "%s cannot define a relation with abstract class %s" % (self.class._name__, to._meta.object_name)
AssertionError: ForeignKey cannot define a relation with abstract class OtherModel

Please advise.... also let me know if you have any questions or don't understand something that I am explaining. The file that I working with is really complex, so I didn't want to post the whole thing since I knew that it is breaking on this one relationship.

Django: Model Inheritance: FK & M2M

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

文章

问答

视频

教程

学习中心

腾讯云实验室

直播

竞赛

腾讯云代码分析专区

腾讯iOA零信任安全管理系统专区

腾讯云架构师技术同盟交流圈

腾讯云数据库专区

腾讯云智能顾问专区

腾讯云原生专区

腾讯混元专区

腾讯云TCE专区

腾讯云Lighthouse专区

腾讯云HAI专区

腾讯云Edgeone专区

腾讯云存储专区

腾讯云智能专区

腾讯轻联专区 

腾讯云开发专区

TAPD专区

腾讯轻量云游戏服专区

腾讯云最具价值专家

腾讯云架构师技术同盟

腾讯云创作之星

腾讯云开发者先锋

腾讯云代码助手

云原生构建

TAPD 敏捷项目管理

Cloud Studio

SDK中心

API中心

命令行工具

涵盖代码开发、场景应用、自动测试全流程，助你从零构建专属AI助手

一站式MCP教程库，解锁AI应用新玩法

聚焦“写作效率、视觉美观与运行性能”三方面进行全面升级，为您提供更高效、稳定的创作环境

社区富文本&Markdown编辑器全新改版上线，欢迎大家体验!

诚挚邀请您参与本次调研，分享您的真实使用感受与建议。您的反馈至关重要，感谢您的支持与参与！

社区新版编辑器体验调研

我试着这么做：使用这种风格这被保存为公共/抽象. isclass OtherModel(models.Model):   something = Charfield(max_length=100)   class Meta:            abstract = Trueclass Base(models.Mod...

问Django:模型继承: FK & M2M
EN

Stack Overflow用户

社区

活动

圈层

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问Django:模型继承: FK & M2MEN