Bdtjtk

Django 2.1, python 3.6

I have two models

house = (

    ('Clubs','Clubs'),

    ('Diamonds','Diamonds'),

    ('Hearts','Hearts'),

    ('Spades','Spades'),

    )



class Card(models.Model):

    id           = models.CharField(max_length=36, blank=False, primary_key=True)

    card         = models.CharField(max_length=15, blank=False)

    number       = models.IntegerField(default=1)

    house        = models.CharField(choices=house)



class Deck(models.Model):

    id       = models.CharField(max_length=50, primary_key=True)

    name     = models.Charfield(...)

    card        = models.ManyToManyField(Card, through='DeckCard')



class DeckCard(models.Model):

    deck = models.ForeeignKey(Deck, on_delete=models.cascade)

    card  = models.ForeignKey(Card, on_delete=models.CASCADE)



    @property

    def number_sum(self):

        self._number_sum= self.card.aggregate(total=models.Sum('number'))['total']

        return number_sum

The property field number_sum successfully returns the correct count. However, I want to now group the sum by house? Does anyone know how to do this?

I wasn't as clear as I should have been before and so I have expounded.

Where Card looks like it should

id...name........number...house

1....ace_diamonds..1......diamonds

2....two_diamonds..2......diamonds

3....three_diamonds..3....diamonds

4....four_diamonds...4....diamonds

...

52...king_Spades...13....spades

and Deck looks like

id...name

1...johnsdeck

2...bettysdeck

Suppose DeckCard looks like the following

deck..card

1...ace_diamonds

1...two_diamonds

1...ace_diamonds (yes there can be duplicates)

1...three_hearts

2...ace_hearts

Then the model Deck is each person's set of cards. DeckCard are the physical cards in the deck. and Card contains the properties on the card.

I want to have Deck give some stats about the deck. E.g. total numbers per house.

So in the example I want to have a total count and a count per house
Deck 1
Total: 7 (1+2+1+3)
Diamonds: 4
Hearts: 3
Spades: 0
Clubs: 0

Deck 2
Total: 1
Hearts: 1

This
self._number_sum= self.card.aggregate(total=models.Sum('number')) gives me a total count per deck, or in this case 7. However, I want to have a group by so that I can have a count per house in addition to the total. Does anyone know how to do this.

In the end, I want to put this in a api like so

{  

  card: ...

  numbers: {

            Total:1

            Diamonds:4

            Clubs:0

            Hearts:3

            Spades:0

            }

}

But that is not for this question. I'm pretty sure the best place to put this is on a @property field. I'm just throwing that out there so someone knows the end goal.