Django group by hour

Question

I have the following model in Django.

class StoreVideoEventSummary(models.Model):
    Customer = models.ForeignKey(GlobalCustomerDirectory, null=True, db_col         


        

Answer 1

just break it into two steps

objs = StoreVideoEventSummary.objects.filter(Timestamp__range=(start_time, end_time),
                                                   Customer__id=customer_id,
                                                   Store__StoreName=store)\
    .order_by("Timestamp")

def date_hour(timestamp):
   return datetime.datetime.fromtimestamp(timestamp).strftime("%x %H")

groups = itertools.groupby(objs, lambda x:date_hour(x.Timestamp))
#since groups is an iterator and not a list you have not yet traversed the list
for group,matches in groups: #now you are traversing the list ...
    print group,"TTL:",sum(1 for _ in matches)

this allows you to group by several distinct criteria

if you just want the hour regardless of date just change date_hour

def date_hour(timestamp):
   return datetime.datetime.fromtimestamp(timestamp).strftime("%H")

if you wanted to group by day of the week you just use

def date_hour(timestamp):
   return datetime.datetime.fromtimestamp(timestamp).strftime("%w %H")

Answer 2

I know I'm late here, but taking cues from the doc, https://docs.djangoproject.com/en/1.11/ref/models/querysets/#django.db.models.query.QuerySet.extra

the below filter should work for you.

store_count_events = StoreVideoEventSummary.objects.filter(
    Timestamp__range=(start_time, end_time),
    Customer__id=customer_id,
    Store__StoreName=store
).order_by(
    'Timestamp'
).extra(
    select={
        'hour': 'hour(Timestamp)'
    }
).values(
    'hour'
).annotate(
    TotalPeople=Sum('PeopleCount')
)

Answer 3

Building off your original code, could you try:

store_count_events = StoreVideoEventSummary.objects.filter(Timestamp__range=(start_time, end_time), Customer__id=customer_id, Store__StoreName=store)\
    .extra({
        "hour": "date_part(\'hour\', \"Timestamp\")"
    })\
    .values("hour")\
    .group_by("hour")\
    .annotate(TotalPeople=Sum("PeopleCount"))