How to get related set models without hit database in Django

Question

Here you'll always get two separate db calls, and adding select_related() anywhere won't help at all. One extra db call isn't that significant.

<ul>
{% for obj in myobjects %}
    <li>{{ myobj.name }}</li>
    <ul>
         {% for relobj in myobj.backwardsrelationship_set.all %} {# hit database at every row #}
         <li>{{ relobj.name }}</li>
         {% endfor %}
    </ul>
{% endfor %}
</ul>

Any idea here?

Answer 1

I found the solution.

prefetch_related can solve this

Publisher.objects.filter(city='NY').prefetch_related('book_set')