像这样使用 python 3.5.2 和 django 1.11 多表继承:
class Artist(ArtistParent):
biography = models.CharField(max_length=255, blank=True, null=True)
avatar = models.ImageField(null=True, blank=True, upload_to=settings.IMAGES_FOLDER)
owner = models.ForeignKey("accounts.User", related_name="my_artists",
null=True, blank=True, on_delete=deletion.SET_NULL)
class SimilarBand(ArtistParent):
pass
每个工作都很好,但使用 ORM 接口:
>>> ArtistParent.objects.all().delete()
(0, {})
>>> SimilarBand.objects.all().delete()
(0, {})
>>> ArtistParent.objects.all().delete()
(0, {})
>>> SimilarBand.objects.all().delete()
(0, {})
>>> SimilarBand.objects.create(name="Similar Band Test")
<SimilarBand: Similar Band Test>
>>> SimilarBand.objects.all()
<QuerySet [<SimilarBand: Similar Band Test>]>
>>> ArtistParent.objects.all()
<QuerySet [<ArtistParent: Similar Band Test>]>
>>> SimilarBand.objects.all().count()
1
>>> ArtistParent.objects.all().count()
1
>>> len(ArtistParent.objects.all())
1
>>> len(SimilarBand.objects.all())
1
>>> [print(o) for o in ArtistParent.objects.all()]
Similar Band Test
[None]
>>> [print(o) for o in SimilarBand.objects.all()]
Similar Band Test
[None]
>>> [print(o) for o in ArtistParent.objects.filter(similarband__isnull=False)]
Similar Band Test
[None]
>>>
我的错误是关于遍历查询集带来的第二个 None ,这正常吗?或者是经理的错误?
但是,如果我使用这样的 for 构造,它就可以正常工作:
>>> [print(i) for i in list(SimilarBand.objects.all())]
Similar Band Test
[None]
>>> for i in list(SimilarBand.objects.all()):
... print(i)
...
Similar Band Test
无论哪种方式,我都在使用 serpy 序列化程序,并在传递查询集时给出错误。
谢谢您的帮助
更新:
按照评论/答案中的指示,我错过了使用列表理解结构(我的错误)
两者都不需要对 serpy lib 做任何事情,我的错误变成了框架的问题:
[![