Django:如何向后跟随ForeignKey ('self')

Question

class Achievement(MyBaseModel):
    parent_achievement = models.ForeignKey('self', blank=True, null=True, help_text="An achievement that must be done before this one is achieved") # long name since parent is reserved

我可以 :

Achievement.objects.get(pk="1").parent_achievement

太好了但是我如何让所有的 child 呢？

Achievement.objects.get(pk="1").parent_achievement_set

不起作用(可能应该在它周围有更多记号)，而且我在搜索时没有看到太多内容。

是否可以？陷入SQL？

Answer 1

默认情况下，django将调用相反的模型名称，后跟“_set”，因此它将是

Achievement.objects.get(pk="1").achievement_set

如果那不适合您，请使用 related_name可选参数 models.ForeignKey:

class Achievement(MyBaseModel):
    parent_achievement = models.ForeignKey(
        'self', 
        blank=True, 
        null=True, 
        help_text="An achievement that must be done before this one is achieved",
        related_name="child_achievement_set"
    ) # long name since parent is reserved

Achievement.objects.get(pk="1").child_achievement_set