#26010: I need to count objects in a queryset by year and month -------------------------------------+------------------------------------- Reporter: mahmoodkhan | Owner: nobody Type: New feature | Status: closed Component: Database layer | Version: master (models, ORM) | Severity: Normal | Resolution: invalid Keywords: Queryset.extra | Triage Stage: | Unreviewed Has patch: 0 | Needs documentation: 0 Needs tests: 0 | Patch needs improvement: 0 Easy pickings: 0 | UI/UX: 0 -------------------------------------+-------------------------------------
Comment (by mahmoodkhan): Thanks! much appreciated. Replying to [comment:1 charettes]: > Hi mahmoodkhan, > > You don't `extra()` to achieve this. There's already a couple of open tickets that you can relate to (#25774 comes to mind) but you should annotate your queryset with a [https://docs.djangoproject.com/en/1.9/ref/models/lookups/#transform- reference Transform] in order to extract the year and months. > > If you don't want to write your own Transform subclass you can use the undocumented `MonthTransform` and `YearTransform` to annotate your queryset: > > {{{#!python > from django.db.models.lookups import MonthTransform as Month, YearTransform as Year > > Item.objects.annotate( > year=Year('date'), > month=Month('date'), > ).values('year', 'month').annotate(count=Count('pk')) > }}} > > Keep in mind that you're relying on a private API (used internally to implement the `__month` and `__year` lookups) that might be moved around or replaced. > > Once `values()` allows transforms and lookups you should be able to simply do this: > > {{{#!python > Item.objects.values('date__year', 'date__month').annotate(count=Count('pk')) > }}} -- Ticket URL: <https://code.djangoproject.com/ticket/26010#comment:2> Django <https://code.djangoproject.com/> The Web framework for perfectionists with deadlines. -- You received this message because you are subscribed to the Google Groups "Django updates" group. To unsubscribe from this group and stop receiving emails from it, send an email to django-updates+unsubscr...@googlegroups.com. To post to this group, send email to django-updates@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/django-updates/069.9d1a8450c71ed4cdbff1c7bb426fe30d%40djangoproject.com. For more options, visit https://groups.google.com/d/optout.