On Tue, 2008-02-12 at 13:36 +0100, Hanne Moa wrote: > On Feb 12, 2008 12:51 PM, Malcolm Tredinnick <[EMAIL PROTECTED]> wrote: > > On Tue, 2008-02-12 at 12:44 +0100, Hanne Moa wrote: > > > On Feb 12, 2008 12:16 PM, Malcolm Tredinnick <[EMAIL PROTECTED]> wrote: > > > > On Tue, 2008-02-12 at 12:11 +0100, Hanne Moa wrote: > > > > > Each org only has a single region, and in the old web-interface the > > > > > region-data is shown as a drop-down-list (<select>) where you can > > > > > choose one and only one. So: org.region == region.id, there can be > > > > > many orgs in a region but only one region per org. > > > > > > > > Which means it's many-to-one, not one-to-one. If you were to draw a > > > > picture of your table rows, many rows would (potentially) be pointing to > > > > a single row in the org table. That's many-to-one. > > > > > > > > In Django a many-to-one relation is represented by a ForeignKey field. > > > > > > I'm using a ForeignKey-field for it now, but I don't see anywhere how > > > to make it behave as in the old system: in Django's admin-interface > > > for org the foreignkey is shown as a drop-down *but with nothing > > > selected*. > > > > > > When looking at the examples in the tutorial: Poll/Choice, a Poll can > > > have several Choices, but a Choice can have only a single Poll. But > > > org->region is *the other way around*. One Poll containing many > > > Choices vs. one org having one region. The fact that one region have > > > many orgs is irrelevant as region will never be editable or visible > > > anywhere else but as linked from org. > > > > > > So, how do I do that? > > > > Put the ForeignKey on the "many" side of the relation. In your case, it > > looks like it goes on the "org" model, since there are many orgs to a > > region. > > I already have: > > class Region(models.Model): > id = models.IntegerField(unique=True, primary_key=True) > region = models.CharField(maxlength=32) > location = models.CharField(maxlength=32) > class Meta: db_table = 'region' > > def __str__(self): > return '%s (%s)' % (self.region, self.lokasjon)
Here's the problem: your __str__ method will be throwing an exception because the lokasion attribute doesn't exist. > > class Org(models.Model): > id = models.IntegerField(unique=True, primary_key=True) > .. > region = models.ForeignKey(Region, db_column = 'id') #x, Region.id By default, ForeignKeys refer to the primary key of the related model. So you can do away with the db_column attribute here if you want to be more succient. [...] > http://www.djangoproject.com/documentation/faq/ > > This FAQ, which I read before I came here, and which I assume is > pretty official, doesn't contain answers to my type of question. So, > is there another FAQ for such? The obvious google didn't find any. Any FAQ file is a subset of frequently ask questions. It doesn't contain every single question ever asked. Not even every question asked more than once. However a lot of questions of already been asked previously on this very mailing list. So I am suggesting that you do the natural things and search the mailing list archives (or just use Google and don't even restrict it to the django-user archives). View the mailing list as an ever-growing, live list of frequently asked questions (and multiple answers). Regards, Malcolm -- Borrow from a pessimist - they don't expect it back. http://www.pointy-stick.com/blog/ --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~----------~----~----~----~------~----~------~--~---
