Looks like a typo. Does the rest of the example make sense and work if that line is changed to "Book.objects.first().chapters"?
On Tuesday, April 26, 2016 at 12:50:31 PM UTC-4, Ankush Thakur wrote: > > Folks, I'm having exceptional trouble understanding annotate(), > aggregate(), and their various combinations. I'm currently stuck here: > https://docs.djangoproject.com/en/1.9/topics/db/aggregation/#combining-multiple-aggregations > > The example here uses Book.objects.first().chapters.count(), but there's > no chapters model or field at the start of the tutorial. It's frustrating, > to say the least. Even if I set up a separate application to test this > myself, what do I make of "chapters"? Is it another model with many-to-many > relation with Book? When I ran an example with the following models: > > class Author(models.Model): > name = models.CharField(max_length=100) > age = models.IntegerField() > > class Book(models.Model): > name = models.CharField(max_length=300) > chapters = models.IntegerField() > authors = models.ManyToManyField(Author) > > I got: > > >>> Book.objects.first().chapters.count() > Traceback (most recent call last): > File "<console>", line 1, in <module> > AttributeError: 'int' object has no attribute 'count' > >>> > > So basically, I feel like I'm screwed. Please help. > -- 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 [email protected]. To post to this group, send email to [email protected]. 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/6527650e-9b58-47a5-8e65-95fd976902cb%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
