How can i query for objects in current year , current month in django

Question

I need to find total objects created in

1. current year
2. current month
3. last month
4. last year

I am thinking like this

    this_year = datetime.now().year
    last_year = datetime.now().year -1
    this_month = datetime.now().month
    last month = (datetime.today() - timedelta(days=30)).month

Use like

Order.objects.filter(created_at__month=this_month)

The problem is

1. last_month i want is calendar month not 30 days back
2. i am not sure whether created_at__month=this_month will match current month or same month in previous year
3. is it possible to get all counts in single query

Answer 1

today = datetime.datetime.now()

1 Current year

Order.objects.filter(created_at__year=today.year)

2 Current month

Order.objects.filter(created_at__year=today.year, created_at__month=today.month)

3 Last month

last_month = today.month - 1 if today.month>1 else 12
last_month_year = today.year if today.month > last_month else today.year - 1

Order.objects.filter(created_at__year=last_month_year, created_at__month=last_month)

4 Last year

last_year = today.year - 1
Order.objects.filter(created_at__year=last_year)

5 Single Query

As last year + current year includes last month and current month, and all orders>= last_year includes current year, the query is super simple:

Order.objects.filter(created_at__year__gte=last_year)