在对象列表中查找字段的分布？

Question

I have a list of objects. Each object has a field called grade whose value is between 0 and 5. Now I want to see the distribution of this field across my list of objects. Is there any way to find it?

I know I can iterate over the whole objects and find it out but I don't want to do that.

Answer 1

As near as I can tell, using a table Table with a grade column you need something like this:

counts = Table.objects.annotate(count=Count("grade", distinct=True)

This adds a count attribute to each member of the counts query set, which you can access just like a regular database column.