django annotate not working properly -


i have 2 models saleitem , product. here want count of products in saleitem table . used annotate not getting desired result

class saleitem(models.model):     product = models.foreignkey(product, related_name="sale_products")     quantity = models.positiveintegerfield()   class product(models.model):     name = models.charfield(max_length=128)

views.py

saleitem.objects.values("product__name").annotate(count=count("product__name"))

when tried in shell. getting products count 1 

<queryset [{'count': 1, 'product__name': u'rice'}, {'count': 1, 'product__name': u'rice'}, {'count': 1, 'product__name': u'mango'}, {'count': 1, 'product__name': u'mango'}, {'count': 1, 'product__name': u'mango'}, {'count': 1, 'product__name': u'apple'}, {'count': 1, 'product__name': u'apple'}, {'count': 1, 'product__name': u'apple'}, {'count': 1, 'product__name': u'apple'}, {'count': 1, 'product__name': u'grape'}, {'count': 1, 'product__name': u'grape'}, {'count': 1, 'product__name': u'grape'}, {'count': 1, 'product__name': u'grape'}, {'count': 1, 'product__name': u'grape'}, {'count': 1, 'product__name': u'grape'}, {'count': 1, 'product__name': u'grape'}, {'count': 1, 'product__name': u'grape'}]>

here want totalcount of each product in saleitem table. how can that. please me.

check this: https://docs.djangoproject.com/en/1.11/topics/db/aggregation/#cheat-sheet

in example has this: 

each publisher, each count of books "num_books" attribute. >>> django.db.models import count >>> pubs = publisher.objects.annotate(num_books=count('book')) >>> pubs <queryset [<publisher: baloneypress>, <publisher: salamipress>, ...]> >>> pubs[0].num_books 73

applying case, think should this:

sale_items = saleitem.objects.annotate(product_count=count("product__name"))

then can 

sale_items[0].product_count

this return product count assoicated 1 sale item


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