[Answered ]-Django Aggregation: highest sum in categories

by

1👍

✅

You can order by the cost and obtain the last one, so:

def metrics(request):
    topcat = CostCat.objects.annotate(sum=Sum('cost__amount')).latest('sum')
    return render(request, 'metrics.html', {'topcat': topcat})

or if it is possible that there are categories without a Cost, you can use nulls_last=True [Django-doc]:

from django.db.models import F

def metrics(request):
    topcat = CostCat.objects.annotate(sum=Sum('cost__amount')).earliest(
        F('sum').desc(nulls_last=True)
    )
    return render(request, 'metrics.html', {'topcat': topcat})
👤willeM_ Van Onsem

Leave a comment