Django模型字段的计算总和

Question

class Transaction:
    amount = models.FloatField()

Now I calculate the sum of amount

transactions = Transaction.objects.all()
amount = 0
for transaction in transactions:
    balance = transaction.amount
    amount += balance

I know it is calculate by using agreegate. But is this possible by this way or another way ?

Answer 1

ModelName.objects.aggregate(Sum('field_name'))

这是文档

Answer 2

Not sure why not use aggregate, if you wanna iterate you can try

transactions = Transaction.objects.values_list('amount', flat=True)
amount = sum(list(transactions))