Group by Day in Django

Navigation
1

Does anyone have an example of a "bat-ready" grouping by date? I've tried all of this here ... 

Subscription.objects.extra(select={'day': 'date(created_at)'}).values('day').annotate(available=Count('created_at'))

from django.db.models.aggregates import Count
Subscription.objects.extra({'date':"date(created_at)"}).values('date').annotate(count=Count('id'))



from django.db import connection
from django.db.models import Count

select = {'day': connection.ops.date_trunc_sql('day', 'created_at')}
Subscription.objects.extra(select=select).values('day').annotate(number=Count('id'))

But none returned what I want: 

2016-01-22, 10
2016-01-21, 5
2016-01-15, 7
    
asked by anonymous 22.01.2016 / 23:08

2 answers

0

Django aggregation, group by day 

import datetime
import itertools
qs = Subscription.objects.values('created_at').values('created_at')
grouped = itertools.groupby(qs, lambda d: d.get('created_at').strftime('%Y-%m-%d'))
[(day, len(list(this_day))) for day, this_day in grouped]

Return 

[('2016-01-24', 7),
 ('2016-01-22', 13),
 ('2016-01-21', 5),
 ('2016-01-15', 9),
 ('2016-01-14', 1),
 ('2016-01-09', 20)]

link

    
24.01.2016 / 05:05
1

* To group by day, just group by date .

Being of type DateField , just do the following: 

>>> from django.db.models import Count
>>> Subscription.objects.values('created_at').annotate(number=Count('id'))
[{'number': 1, 'created_at': datetime.date(2015, 12, 5)}]

If the type is DateTimeField , I converted it to type DateField using conditionals and functions: 

>>> from django.db.models import DateField, Case, F
>>> Subscription.objects.annotate(tipo_datefield=Case(default=F('created_at'), output_field=DateField())).values('tipo_datefield').annotate(number=Count('id'))

Another way to accomplish this (not yet in the documentation) is to use Date to extract the day: 

from django.db.models.expressions import Date
Subscription.objects.annotate(
    day=Date('created_at', 'day')
).values('day').annotate(number=Count('id'))
    
22.01.2016 / 23:54
Date and Time Update to check if it is online Scrollbar does not descend to the end