I have a feeling the solution to this is very simple, but as new to Django I am not able to figure it out...
Given the following QuerySet:
<QuerySet [{'id': 2, 'prodclassQuery_id': 1, 'prodDescription': 'Hofbräu Kellerbier 500 ml', 'prodPrice': Decimal('6.50')}, {'id': 1, 'prodclassQuery_id': 1, 'prodDescription': 'Tonic Water 300 ml', 'prodPrice': Decimal('4.50')}, {'id': 3, 'prodclassQuery_id': 2, 'prodDescription': 'Coxinha 6 unidades', 'prodPrice': Decimal('8.00')}, {'id': 3, 'prodclassQuery_id': 2, 'prodDescription': 'Coxinha 6 unidades', 'prodPrice': Decimal('8.00')}]>I want to aggregate the repeated elements (based on id) e produce the following QuerySet, adding the field poQty_ to represent the quantity of repeated elements (products in my case...):
<QuerySet [{'id': 2, 'prodclassQuery_id': 1, 'prodDescription': 'Hofbräu Kellerbier 500 ml', 'prodPrice': Decimal('6.50'), 'poQty_': 1}, {'id': 1, 'prodclassQuery_id': 1, 'prodDescription': 'Tonic Water 300 ml', 'prodPrice': Decimal('4.50'), 'poQty_': 1}, {'id': 3, 'prodclassQuery_id': 2, 'prodDescription': 'Coxinha 6 unidades', 'prodPrice': Decimal('8.00'), 'poQty_': 2}]>What I tried so far with annotate() in views.py is not working, and the results of orders_aggris the same original QuerySet:
def display_orders(request): orders = Order.objects.all().order_by('id', 'orderTable', 'menuQuery') for j in orders: print(j.prodQuery.values(),) # original QuerySet orders_aggr = Order.objects.annotate(poQty_=Count('prodQuery__id')).order_by('id', 'orderTable', 'menuQuery') for j in orders_aggr: print(j.prodQuery.values(),) context = {'orders': orders,'orders_aggr': orders_aggr } return render(request, 'orders.html', context)Would anyone give please some help? Thanks !!Further information:
models.py
class Product(models.Model): prodclassQuery = models.ForeignKey(ProductClass, on_delete=models.PROTECT, verbose_name='Product Class', default=1) prodDescription = models.CharField(max_length=255, verbose_name='Product') prodPrice = models.DecimalField(max_digits=6, decimal_places=2, verbose_name='Price') class Meta: ordering = ['prodclassQuery', 'prodDescription'] def __str__(self): return self.prodDescriptionclass Menu(models.Model): menuActive = models.BooleanField(verbose_name='Active?', default=False) menuDescription = models.CharField(max_length=255, verbose_name='Menu') prodQuery = models.ManyToManyField(Product, verbose_name='Product') class Meta: ordering = ['menuDescription',] def __str__(self): return self.menuDescriptionclass Order(models.Model): orderUser = models.ForeignKey(User, on_delete=models.SET_NULL, null=True, blank=True) orderDtOpen = models.DateTimeField(auto_now_add=True) orderDtClose = models.DateTimeField(auto_now=True) orderOpen = models.BooleanField(default=True, verbose_name='Open?') orderTable = models.CharField(max_length=25, verbose_name='Table') menuQuery = models.ForeignKey(Menu, on_delete=models.PROTECT, verbose_name='Menu', default=1) prodQuery = models.ManyToManyField(Product, through='ProductOrder') class Meta: models.UniqueConstraint(fields=['orderTable'], condition=models.Q(orderOpen=True), name='unique_open_order_table', violation_error_message='This table has already a open order') def save_model(self, request, obj, form, change): obj.orderuser = request.user super().save_model(request, obj, form, change)class ProductOrder(models.Model): poOrder = models.ForeignKey(Order, on_delete=models.CASCADE, verbose_name='Order', default=1) poStatus = models.BooleanField(default=True, verbose_name='Order Status') prodQuery = models.ForeignKey(Product, on_delete=models.CASCADE, verbose_name='Product', default=1)