Annotating multiple Sum() objects gives wrong answer

[tBuLi]

This is best explained with an example:

queryset = Member.objects.annotate(payed=Sum('payment__amount'))
queryset = Member.objects.annotate(discount=Sum('membership__discount__amount'))

These give the right payed and discount amount for the member, whereas

queryset = Member.objects.annotate(discount=Sum('membership__discount__amount'), payed=Sum('payment__amount'))

gives a value for payed which is a factor 2 higher, and the discount is a factor 3 higher. Using exactly the same syntax with Count() gives the correct answer in both cases, so I suspect something goes wrong with Sum().

using distinct = True does not matter.

[Karen Tracey]

This sounds like #10060 to me.