Django admin list display optimize queryset

Question

In User model i have a method:

@cached_property
    def income(self):
        return PartnerIncome.objects.all().aggregate(Sum('income'))['income__sum']*self.share_of_profit

PartnerIncome model:

class PartnerIncome(models.Model):
    title = models.CharField(max_length=255)
    income = models.FloatField(default=0)

Now i want to show 'inccome' in list_display=('income', ) at admin panel, but each object make extra query to database. How i can make PartnerIncome.objects.all().aggregate(Sum('income')) as a global variable for admin change list...

Answer 1

How about just overriding the get_queryset method in your ModelAdmin?

class UserAdmin(admin.ModelAdmin):

    list_display = ('income', ...)

    def income(self, obj):
        return obj.income

    def get_queryset(self, request):
       queryset = super(UserAdmin, self).get_queryset(request)
       # you logic here to `annotate`the queryset with income
       return queryset

Documentation on aggregation:

https://docs.djangoproject.com/en/dev/topics/db/aggregation/

Without me really understanding your models and business logic.. here's a snippet from my own code as an example:

class AuthorAdmin(admin.ModelAdmin):
    list_display = ('__str__', 'books_count',)

    def books_count(self, obj):
        return obj.books_count

    def get_queryset(self, request):
        return super(AuthorAdmin, self).get_queryset(
            request).annotate(books_count=Count('books'))