Thank you very much for that Javier. After flailing around with raw SQL for a while I realised that Django has conveniently provided a powerful set of field lookups that I did not know about.
I have ended up doing this, which is a million times simpler than what I was previously attempting: <views.py> ... date = datetime.date.today() day_of_the_week = date.weekday() last_date_in_week = date + datetime.timedelta(days = 7 - day_of_the_week) week = Todo.objects.filter(owner__id = user.id).filter(due_date__lte=last_date_in_week).filter(due_date__gt=date) ... </views.py> This gives me 'todo' objects from tomorrow until the end of the week, which is what I want. On Mar 1, 3:35 am, Javier Guerra Giraldez <jav...@guerrag.com> wrote: > On Wed, Feb 29, 2012 at 3:16 PM, Tom <t.scr...@gmail.com> wrote: > > Is it not possible to filter based on a property? > > queries are compiled to SQL to be sent and processed at the database; > properties are Python code, the database knows nothing about them. > that's why the compiler only allows you to use database fields on a > filter > > > What is the correct method for doing this? > > the generic answer is to do it in Python, something like: > > result = [ record in queryset if record.property == value ] > > but this can be very inefficient, and nowhere as flexible as Django's > querysets. > > much better is to translate the criteria into something the database > can process. In this case, find the beginning and end of the current > week and use a range filter. > > -- > Javier -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-users@googlegroups.com. To unsubscribe from this group, send email to django-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
