Is it possible to perform a subquery on a QuerySet using another QuerySet?
For example:
开发者_高级运维q = Something.objects.filter(x=y).extra(where=query_set2)
Short answer: No. The extra
method doesn't expect querysets to be passed in.
If you think about it a bit, it makes sense. Querysets are an abstraction used to represent the results of a fetch operation on the database and extra
is a convenient way of attaching custom fields from the database to a queryset. Unless you change the fundamental nature of extra
to mean "custom filtering with another queryset" this will not work.
I may understand your question in two ways.
You can specify multiple variables in your filter parameters, for example :
q = Something.objects.filter(x=y, w=z)
You want to make what is called a "join" in SQL. This can be done via the aggregation system of Django, see the official Django Official Documentation.
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