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    <p>In the following, I tried to take into account all your constraints: filtering on fields of List, on fields of Item, counting items , and grouping by list.</p> <p>The solution I see is that you could use values() (here is the django doc about this : <a href="http://docs.djangoproject.com/en/dev/topics/db/aggregation/#values" rel="nofollow">http://docs.djangoproject.com/en/dev/topics/db/aggregation/#values</a>)</p> <pre><code>from django.db.models import Count lists = list(List.objects.filter(user=user)) items=Item.objects.values(list).filter(archived=False,list__in=lists).annotate(count=Count("id")) #you will get a list of dicts of the form [{'count':2,'list':5},...] where 5 is the id of the list #now, you can match you list with you item counts in python list_items_count_dict={} for item in items: list_items_count_dict[item['list']]=item['count'] for list in lists : list.item_count = list_items_count_dict.get(list.id) </code></pre> <p>That will make only 2 queries, one for getting the lists, the other for computing the item counts. Afterwards, you will have two loops (that could probably be replaced by list comprehension one-liners ), but only for the lists you are interested in.</p> <p>afterwards, in your template, you can use </p> <pre><code>{{list.item_count}} </code></pre> <p>There might be a more elegant option, but that is what I have found right now. I am also certain that you could reduce the number of query to one by using custom sql.</p> <p>Disclaimer: I have not tested this code, but I have tested similar code on similar models. You could have problems because <code>list</code> is one of the keyword of the Python language.</p>
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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