python - Get all "grand"-Children of a given Model -


im trying learn python/django @ moment , came across following problem. let's have 3 models:

model category(models.model)     name = models.charfield(max_length64)  model subcategory(models.model)     category    = models.foreignkey(category)     name        = models.charfield(max_length64)  model animal(models.model)     subcategory = models.foreignkey(subcategory)     name = models.charfield(max_length64)

now, example, if searches category, want have animals in of subcategories of given main category. ( hope not complicated)

so question efficient way this?

thanks in advance!

you can query like:

animals = animal.objects.filter(subcategory__category__id=category_id)

or, if have access category object, 

animals = animal.objects.filter(subcategory__category=category)

please note model object definition class <classname> , not model <classname> example: model animal should class animal


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