Looking up relative dates from Django DateTimeField

django, python

Solution

Pass `datetime.datetime` object (substracted by `datetime.timedelta` object):

>>> import datetime
>>> now = datetime.datetime.now()
>>> now
datetime.datetime(2013, 12, 29, 21, 54, 30, 836000)
>>> now - datetime.timedelta(days=1)
datetime.datetime(2013, 12, 28, 21, 54, 30, 836000)

import datetime

cars = MyClass.objects.filter(date__lt=datetime.datetime.now() - datetime.timedelta(days=1))

UPDATE Comment by Mikko Ohtamaa:

Also to avoid problems with timezones I recommend using `timezone.now()` instead of `datetime.datetime.now()` (available since Django 1.4)

import datetime
from django.utils import timezone

cars = MyClass.objects.filter(date__lt=timezone.now() - datetime.timedelta(days=1))

Problem

model: ``` class MyClass(models.Model): car = models.ForeignKey(Car) date = models.DateTimeField(auto_now=True, auto_now_add=True) ``` sql: ``` SELECT car FROM cars_myclass WHERE date < NOW() - INTERVAL 1 DAY; ``` So, I have something like: ``` cars = MyClass.objects.all().filter(date < ... ) ``` But how to write `NOW() - INTERVAL 1 DAY` ? Thanks.

Original source