> thanks for reply, but i don't quite understand :( sorry i'm newbie > here.... > First my models.py is like this > class DigitalSignage(models.Model): > DS_ID = integerField() > > class tableSlot(models.Model): > ds_id =models.ManyToManyField(DigitalSignage) > > class columnSetup(models.Model): > tableList =models.ManyToManyField(tableSlot) > > so in my views.py like this:
> > > ds = DigitalSignage.objects.get(pk=ds_id) Here, you are retrieving a single object, namely a DigitalSignage (as defined in your model). The <m2m-relation>_set identifier will work for objects, as below. > > tableslots = ds.tableslot_set.all() Here, you're retrieving all tableslots, which results in a QuerySet. It is a QuerySet of your tableSlot model, but it's not the model itself. A QuerySet allows filtering, but you cannot directly retrieve any of the relations defined in your models, since it's not the model itself. Have another look at http://www.djangoproject.com/documentation/db-api/#many-to-many-relationships You'll see that the <m2m-relation>_set is used for an object, not a QuerySet. > > > columnsetups = tableslots.columnsetup_set.all() > > so now if i change upwards... that's mean my models.py should be > like this: > class DigitalSignage(models.Model): > DS_ID = integerField() > > class columnSetup(models.Model): > field1 = models.charField() > > class tableSlot(models.Model): > ds_id =models.ManyToManyField(DigitalSignage) > columnList =models.ManyToManyField(columnSetup) Changing your models has nothing to do with it. Therefore, continuing with the model defintion you originally had (top of this mail), you should probably access things from the other side: ds = DigitalSignage.objects.get(pk=ds_id) tableslots = tableSlot.objects.filter(ds_id=ds) # note: not using ds.id. See also note below Also, have another good luck at http://www.djangoproject.com/documentation/db-api/#lookups-that-span-relationships Lastly, I can suggest some renaming, to stay with the usage in Python and Django. Has nothing to do with the problem, so consider it free (and possibly unwanted) advice: - model names start with a Capital (TableSlot instead of tableSlot); as you do for DigitalSignage. - m2m relations are often named as the plural of the relation they refer to. So ds_id should become something like digital_signages (or signages, if you consider that too long). In particular, the ds_id naming is rather badly chosen, since it should reflect an object, not the database id of that object (don't think database-level, think object-level). It is indeed an id (integer) in the database, but if you would retrieve if from your model (through a_table_slot.ds_id), it'll show up as a DigitalSignage object, not a number. Good luck. --~--~---------~--~----~------------~-------~--~----~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/django-users?hl=en -~----------~----~----~----~------~----~------~--~---
