How do I use a dictionary to update fields in Django models?

Question

Suppose I have a model like this:

class Book(models.Model):
    num_pages = ...
    author = ...
    date = ...

Can I create a dictionary,

Answer 1

If you know you would like to create it:

Book.objects.create(**d)

Assuming you need to check for an existing instance, you can find it with get or create:

instance, created = Book.objects.get_or_create(slug=slug, defaults=d)
if not created:
    for attr, value in d.items(): 
        setattr(instance, attr, value)
    instance.save()

As mentioned in another answer, you can also use the update function on the queryset manager, but i believe that will not send any signals out (which may not matter to you if you aren't using them). However, you probably shouldn't use it to alter a single object:

Book.objects.filter(id=id).update()