pk__in 在 Django 中是什么意思？

Question

Model.objects.filter(pk__in=[list of ids])

and

Model.objects.filter(pk__in=[1,2,3])

How do I show this data in a template?

def xx(request):
    return HttpResponse(Model.objects.filter(pk__in=[1,2,3]))

Answer 1

It means, give me all objects of model Model that either have 1 , 2 or 3 as their primary key.

See Field lookups - in .

You get a list of objects back you can show them in the template like every other list, using the for template tag :

{% for object in objects %}
    Some value: {{ object.value }}
{% endfor %}

To learn how to create a Django application you should read the tutorial or the Django book .

Answer 2

A tricky way to batch select (a best practice when dealing with a lot of data). it would be faster than calling get/get_or_create in a loop due to the fact that only one SQL query is sent.

Try to time this :

Model.objects.filter(pk__in=[list of ids])

and this :

[Model.objects.get(pk=i) for i in ids]

Also note that running on your laptop there is minimal latency when django communicates with the database (production might be different).