Djang中参数重复的条件表达式求和

Question

我有一个查询集。如何对jam=（'16-17'，'17-18'，'18-19'）的'output'求和

develop_queryset = InputCutSew.objects.filter(publish='2019-07-30').exclude(cell_name__isnull=True).exclude(cell_name__exact='').order_by('cell_name', 'jam').values('cell_name','model','jam').annotate\
            (total_output_ot=Sum(Case(When(jam='16-17', jam='17-18', jam='18-19', then='output')))).exclude(total_output_ot__isnull=True)

结果： SyntaxError:关键字参数重复

我已经试过了，但是输出还是分开不求和

.annotate(total_output_ot=Sum(Case(
                                      When(jam='16-17', then='output'),
                                      When(jam='17-18', then='output'),
                                      When(jam='18-19', then='output'),))).exclude(total_output_ot__isnull=True)
<QuerySet [{'cell_name': '13a', 'model': 'superstar', 'jam': '16-17', 'total_output_ot': 10}, {'cell_name': '13a', 'model': 'questar flow', 'jam': '16-17', 'total_output_ot': 20}, {'cell_name': '13a', 'model': 'superstar', 'jam': '17-18', 'total_output_ot': 20}, {'cell_name': '13a', 'model': 'questar flow', 'jam': '17-18', 'total_output_ot': 10}, {'cell_name': '13a', 'model': 'superstar', 'jam': '18-19', 'total_output_ot': 10}, {'cell_name': '13a', 'model': 'questar flow', 'jam': '18-19', 'total_output_ot': 20}, {'cell_name': '13b', 'model': 'superstar', 'jam': '16-17', 'total_output_ot': 10}, {'cell_name': '13b', 'model': 'questar flow', 'jam': '16-17', 'total_output_ot': 20}, {'cell_name': '13b', 'model': 'questar flow', 'jam': '17-18', 'total_output_ot': 10}, {'cell_name': '13b', 'model': 'superstar', 'jam': '17-18', 'total_output_ot': 20}, {'cell_name': '13b', 'model': 'questar flow', 'jam': '18-19', 'total_output_ot': 20}, {'cell_name': '13b', 'model': 'superstar', 'jam': '18-19', 'total_output_ot': 10}]>

Answer 1

也许你应该这样做：

develop_queryset = InputCutSew.objects.filter(publish='2019-07-30').exclude(cell_name__isnull=True).exclude(cell_name__exact='').order_by('cell_name', 'jam').values('cell_name','model','jam').annotate(
    total_output_ot=Case(
        When(jam='16-17', then=Value(17)),
        When(jam='17-18', then=Value(18)),
        When(jam='18-19', then=Value(19)),
    ), output_field=IntegerField()
).exclude(total_output_ot__isnull=True)


sum_of_total_output_ot = develop_queryset.aggregate(val = Sum('total_output_ot')).get('val')