Django orm get latest for each group

python django django-queryset django-orm

If your DB is postgres which supports distinct() on field you can try

Score.objects.order_by('student__username', '-date').distinct('student__username')

python django django-queryset django-orm

This should work on Django 1.2+ and MySQL:

Score.objects.annotate(  max_date=Max('student__score__date')).filter(  date=F('max_date'))

python django django-queryset django-orm

I believe this would give you the student and the data

Score.objects.values('student').annotate(latest_date=Max('date'))

If you want the full Score records, it seems you will have to use a raw SQL query: Filtering Django Query by the Record with the Maximum Column Value

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