Hi Ram, I suggest you open a new feature request to document ForeignObject as a public API.
Cheers, Simon Le dimanche 19 juin 2016 02:26:29 UTC-4, Ram Jayaraman a écrit : > > Hi Simon, > > Thanks a lot for the response again! I really appreciate your time. I saw > the uniq_together but didn't realize checks can be silenced in Django. ( `0 > silenced` in the log should have been a clue! ). I silenced it and it does > work great. > > I am not sure if I missed this in the Django docs but this is a really > nice feature for many situations once the models start getting a bit crazy. > I feel this should should be emphasized a bit more in the Docs. I am pretty > terrible at docs so can't offer much help apart there, so it would be great > if the Django docs team can add this. Should I make a ticket for the same ? > > Thanks again > Ram > > On Sunday, June 19, 2016 at 5:30:03 AM UTC+5:30, Simon Charette wrote: >> >> Hi Ram, >> >> As PublisherMediumBilling.publisher and medium are unique together it's >> safe to >> silence the `fields.E310` check failure in this case. >> >> By the way the check was adjusted in Django 1.10 to also take >> `unique_together` >> into account[1]. >> >> Cheers, >> Simon >> >> [1] >> https://github.com/django/django/commit/80dac8c33e7f6f22577e4346f44e4c5ee89b648c >> >> Le samedi 18 juin 2016 13:35:24 UTC-4, Ram Jayaraman a écrit : >>> >>> Hi Simon, >>> >>> Thanks for the post. I just tried this and ForeignObject requires one of >>> the 2 columns being referred to be unique. But thats an interesting object! >>> >>> On Saturday, June 18, 2016 at 8:34:31 PM UTC+5:30, Simon Charette wrote: >>>> >>>> Hi Ram, >>>> >>>> I don't have a complete solution for you but I suggest you take a look >>>> at the >>>> django.db.models.fields.related.ForeignObject class. >>>> >>>> If I'm not mistaken it should allow you to define multi-column >>>> relationships >>>> on both your Article and PublisherMediumBilling models and refer to >>>> them using >>>> the `select_related()` and `prefetch_related()``API while the later >>>> uses Python >>>> to perform in-memory JOINs. >>>> >>>> class Article(models.Model): >>>> publisher = ForeignKey(Publisher, related_name='articles') >>>> medium = ForeignKey(Medium) >>>> billing = ForeignObject( >>>> 'PublisherMediumBilling', from_fields=['publisher', 'medium'], >>>> to_fields=['publisher', 'medium'] >>>> ) >>>> >>>> publisher.articles.select_related('billing') >>>> >>>> Cheers, >>>> Simon >>>> >>>> Le samedi 18 juin 2016 07:09:03 UTC-4, Ram Jayaraman a écrit : >>>>> >>>>> I apologize if this is an old question, I did search SO/google for a >>>>> good few hours. >>>>> >>>>> I have the following models. >>>>> >>>>> Publisher() >>>>> name = CharField() >>>>> >>>>> Medium() >>>>> name = CharField() >>>>> >>>>> Article() >>>>> publisher = ForeignKey(Publisher, related_name="articles") >>>>> medium = ForeignKey(Medium, related_name="articles") >>>>> text = TextField() >>>>> >>>>> PublisherMediumBilling() >>>>> publisher = ForeignKey(Publisher() >>>>> medium = ForeignKey(Article) >>>>> lots_of_other_columns >>>>> ... >>>>> class Meta: >>>>> unique_together = ['publisher', 'medium'] >>>>> >>>>> >>>>> >>>>> I am looking to query all Article from a given publisher, and also >>>>> fetch the related PublisherMediumBilling joining on the columns >>>>> Publisher and Medium, Prefetch() object doesn't seem to quite work >>>>> for this case. >>>>> >>>>> I can of course filter-query for all PublisherMediumBilling and cache >>>>> it and do a in-memory Python JOIN. Is there a way to do through one of >>>>> the >>>>> ORM Apis ? >>>>> >>>> -- You received this message because you are subscribed to the Google Groups "Django users" group. To unsubscribe from this group and stop receiving emails from it, send an email to django-users+unsubscr...@googlegroups.com. To post to this group, send email to django-users@googlegroups.com. Visit this group at https://groups.google.com/group/django-users. To view this discussion on the web visit https://groups.google.com/d/msgid/django-users/e40753f1-07b2-4847-ab86-d8162c648e86%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
