django - Trying filter query depending on a method of a related model -

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class course(models.model):     def is_active(self):       return self.enroll_set.count()>0  class courseevent(models.model):     course = models.foreignkey(course)

i want find events point active courses. like:

events = courseevent.objects.filter(course.is_active=true)

thank you

the answer here: https://docs.djangoproject.com/en/dev/ref/models/querysets/#annotate

you make annotation, it'll filterable field.

it may this:

courseevent.objects.annotate(is_active=count('course__enroll')).exclude(is_active=0)

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