Django 对多个表执行连接

Question

I have the following tables,

class A: 
    field_1 = models.CharField()
    field_2 = models.IntegerField()

class B: 
    a = models.ForeignKey(A, related_name='table_b')
    some_other_field = models.CharField()

class C: 
    b = models.ForeignKey(B, related_name="table_c")
    other_field = models.CharField()

Let's assume ids are provided for objects on table A , I need to get all the C objects that are related to table A through table B . I have the following query, which gives me what I need but I am wondering if there is a better way to do this, I was reading into prefetch_related and select_related but can't wrap my head around on how to use them so far

c_list = C.objects.filter(b__in=B.objects.filter(a__pk__in=table_a_ids))

Also, I would like to group them by other_field

Any help is much appreciated.

Answer 1

No need for .select_related(…) or .prefetch_related(…) . You can filter with:

c_list = C.objects.filter()