Following model relations:
- classA has a non-nullable FK-Field to classC.
- classB has a nullable FK-Field to classC.
I need a list of classA-records that have zero classB-records connected to the common classC-record.
In postgres both queries give me what I want, while in sqlite they both give me a empty result:
ClassA.objects.annotate(num_classb=Count('classc__classbs')).filter(num_classb=0)
ClassA.objects.filter(classc__classbs__isnull=True)
Where do I go wrong? I did not find something about differences in the handling of such filters/annotations between postgres and sqlite
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