Hi a pizza has a one to many relationship with its topping. in a list of pizzas there could be some that have the same topping, like thick, thin etc.
the query would look like select pizza from pizzas where topping = xyz cheers michael ----- Original Message ---- From: Scott Maher <sc...@thereceptor.net> To: django-users@googlegroups.com Sent: Sun, December 27, 2009 9:32:22 AM Subject: Comparing ManyToMany fields Is it possible to filter by the ManyToMany fields? Suppose I have a Pizza model and a Topping model. Topping has a ManyToManyField pointing to Pizza. I now have an instance of a Pizza called mypizza. I would like to now search for all Pizzas with the EXACT same Toppings as mypizza. Intuitively it would like something like this: Pizza.objects.filter(toppings=mypizza.toppings_set) This, naturally, does not work. Any ideas? I'm happy to do some fancy black magic with the models to make it work, or do a custom SQL clause. I just don't know enough SQL to do that. I'm also interested in reasonably alternative ways to model my data if I have a potentially very large set of Pizzas however a limited (although fairly lengthy, 20+) list of toppings that might change periodically. Thanks! -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-us...@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. -- You received this message because you are subscribed to the Google Groups "Django users" group. To post to this group, send email to django-us...@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.
