Question

Let’s say I have a ManyToManyField, from Swallow -=> Coconut.

Also, let’s say that Coconut has a boolean field called “Young.”

For a given swallow, how can I tell if all its coconuts are young?

(What I’m really looking for is not so much the ability to tell whether the swallow’s coconuts are young, but a way to tell whether there is a divergent value among the items in a queryset.)

Answer 1

OK, I figured it out. I need:

swallow.coconuts.aggregate(test=Variance('young'))

If that is 0, I know that they are all the same.