[Fixed]-Django: how to aggregate / annotate over a many-to-many relationship?

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9👍

✅

This would give you the most frequent tag:

from django.db.models import Count
Tag.objects.filter(person__yourcriterahere=whatever [, morecriteria]).annotate(cnt=Count('person')).order_by('-cnt')[0]
👤GJ.

5👍

I need to extract the tag which is connected to the most records within a given Person queryset, together with the count.

I faced a similar problem before. In my case the m2m relationship was defined between Unit and Weapon models. I used the following query to find out the number of weapons used by each Unit and sort them in descending order of number of weapons.

from django.db.models import Count
q = Unit.objects.all().annotate(count = Count('weapons')).order_by('-count')

I would adjust the query for your requirement thus:

q = User.objects.all().annotate(count = Count('tag')).order_by('-count')
👤Manoj Govindan

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