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

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()

Here's an example of create using your dictionary d:

Book.objects.create(**d)

To update an existing model, you will need to use the QuerySet filter method. Assuming you know the pk of the Book you want to update:

Book.objects.filter(pk=pk).update(**d)

Use ** for creating a new model. Loop through the dictionary and use setattr() in order to update an existing model.

From Tom Christie's Django Rest Framework

https://github.com/tomchristie/django-rest-framework/blob/master/rest_framework/serializers.py

for attr, value in validated_data.items():
    setattr(instance, attr, value)
instance.save()