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djangofiltermaxminannotate

Django how to get the value of other fields in annotate Max?


I want to get the value of other fields('status') in annotate Max or Min,how can I do it?

DB

user time status
name_a 2022-01-03 11:23:40.000000 3
name_a 2022-01-03 17:56:41.000000 4
name_a 2022-01-03 22:24:28.000000 1
name_a 2022-01-04 08:24:28.000000 4
name_a 2022-01-04 17:34:19.000000 4
name_b 2022-01-03 08:29:18.000000 1
name_b 2022-01-03 17:34:39.000000 4
# data_1 = Attendance.objects.filter(user__in=user_list)
data_2 = data_1.values('user', 'time__date').annotate(count=Count('time__date')).annotate(s_time=Min("time")).annotate(e_time=Max("time")) 

#print
{'user': 'name_a', 'time__date': datetime.date(2022, 1, 3), 'count': 3, 's_time': datetime.datetime(2022, 1, 3, 11, 23, 40), 'e_time': datetime.datetime(2022, 1, 3, 22, 24, 28)}

i want to get:

{'user': 'name_a', 'time__date': datetime.date(2022, 1, 3), 'count': 3, 's_time': datetime.datetime(2022, 1, 3, 11, 23, 40), 'e_time': datetime.datetime(2022, 1, 3, 22, 24, 28), 's_status': '3', 'e_status': '1' }

I tried adding filter but I didn't succeed

data_2 = data_1.values('user', 'time__date').annotate(count=Count('time__date')).annotate(s_time=Min("time"), e_time=Max("time")).annotate(s_status=F("status"),filter=Q(time=Min("time"))).annotate(e_status=F("status"),filter=Q(time=Max("time")))

Solution

  • You can use Attendance.objects.order_by('time').first().status - get status of min date. And use Attendance.objects.order_by('time').last().status - get status of max date.