[Django]-Django: Annotate the count of the number of duplicate values for each object

by

3👍

✅

The first wish was to use window function, but unfortunately it is not allowed to combine annotate(Window(...)) and filter(...)

The answer is:

from django.db.models import OuterRef, Subquery, Count, Min

subquery = Product.objects.filter(bc_sku=OuterRef('bc_sku')).values('bc_sku')
                          .annotate(dup_count=Count('*'), min_price=Min('product_price'))
Product.objects.filter(product_type='good')
               .annotate(dup_count=Subquery(subquery.values('dup_count')), 
                         min_price=Subquery(subquery.values('min_price')))

You can find details on how this query works in docs

👤Roman Yakubovich

Leave a comment