On 28 January 2011 12:16, sushanth Reddy <sushant...@gmail.com> wrote: > HI, > > How to write joins in django,i have gone through below django documentation > ,but joins are not working for my model >
<snip> > Class working(models.model) > w_name =models.ForeignKey(Profile, db_column='name') > monday = models.IntegerField(null=True, db_column='monday', blank=True) > tuesday = models.IntegerField(null=True, db_column='tuesday', blank=True) > wednesday = models.IntegerField(null=True, db_column='wednesday', > blank=True) > > class Meta: > db_table = u'working' > > lass __str__(self): > return '%s %s %s %s' % ( > self.w_name,self.monday,self.tuesday,self.wednesday) > > class __unicode__(self): > return u'%s %s %s %s' % ( > self.w_name,self.monday,self.tuesday,self.wednesday) > > > I am trying to do join between two tables profile and workingday > > like m=working.objects.filter(name='sushanth').select_related() > > > if i run above query i'll get > > Traceback (most recent call last): > File "<console>", line 1, in <module> > File "/usr/lib/pymodules/python2.6/django/db/models/manager.py", line 129, > in filter > return self.get_query_set().filter(*args, **kwargs) > File "/usr/lib/pymodules/python2.6/django/db/models/query.py", line 498, > in filter > return self._filter_or_exclude(False, *args, **kwargs) > File "/usr/lib/pymodules/python2.6/django/db/models/query.py", line 516, > in _filter_or_exclude > clone.query.add_q(Q(*args, **kwargs)) > File "/usr/lib/pymodules/python2.6/django/db/models/sql/query.py", line > 1675, in add_q > can_reuse=used_aliases) > File "/usr/lib/pymodules/python2.6/django/db/models/sql/query.py", line > 1569, in add_filter > negate=negate, process_extras=process_extras) > File "/usr/lib/pymodules/python2.6/django/db/models/sql/query.py", line > 1737, in setup_joins > "Choices are: %s" % (name, ", ".join(names))) > FieldError: Cannot resolve keyword 'name' into field. Choices are: monday, > tuesday, wednesday, w_name The error message is quite descriptive already. To perform the filter on the foreign key field, you use the name of the foreign key, *not* the name of the field the foreign key refers to. So this will work - m=working.objects.filter(w_name='sushanth').select_related() BTW, setting the name field in your Profile model as the primary key is probably going to be a bad idea - what happens when two people have the same name? An ID is probably better, and if you leave the primary_key argument out, Django will automatically create one for you. Also, in Python, classes should be named in TitleCase by convention. -- 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 django-users+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-users?hl=en.
