[Answered ]-How to get queryset as result for join Query using Django ORM?

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1👍

✅

It will not be possible to fetch all this data in a single query. Well a single query to the server that is. But it’s a single ORM query.

Customer.objects.prefetch_related('c','b').filter(somecondition)

If you could use select_related it would be one SQL query but because the foreign key relations are traversed in reverse you need to use prefetch_related

prefetch_related, on the other hand, does a separate lookup for each
relationship, and does the ‘joining’ in Python. This allows it to
prefetch many-to-many and many-to-one objects, which cannot be done
using select_related, in addition to the foreign key and one-to-one
relationships that are supported by select_related

This is still only three queries.

If you are really really keen on doing this in a single SQL query. Customer.objects.raw() is your friend.

👤e4c5

1👍

Try this

Customer.objects.prefetch_related('b_set', 'c_set').filter(condition)
👤Anoop

0👍

You can’t do it in a single call, but you can certainly do it in two or three with prefetch_related.

A.objects.all().prefetch_related('B', 'C')
👤Daniel Roseman

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