[Answered ]-Django annotation multiply fields

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If just setting distinct=True doesn’t work, then you can use subqueries, as shown in Serafim’s answer here. Given that you mention Vote and Post are a many-to-many relation, you could rewrite e.g. my_votes as a subquery on the through table, something like:

def get_queryset(self):
    my_votes_sq = Subquery(
        Vote.posts.through.objects
         .filter(post_id=OuterRef("pk"), user_id=self.request.user.id)
         .order_by()
         .values("post_id")
         .annotate(count=Count("pk"))
         .values("count"), output_field=IntegerField()
    )
    ...
    return self.queryset.annotate(
        my_votes=Coalesce(my_votes_sq, 0),
        ...
    )

The actual field names for posts, post_id, user_id will depend on your models of course.

👤Vincent Garton

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