How can a do a "greatest-n-per-group" query in django?

django, greatest-n-per-group, join, sql

Solution

You can take a look at similar discussion:

Django Query That Get Most Recent Objects From Different Categories

Problem

(This is the django version of the thread at SQL join: selecting the last records in a one-to-many relationship) Suppose I have a table of customers and a table of purchases. Each purchase belongs to one customer. I want to get a list of all customers along with their last purchase. Can it be done without raw SQL and without multiple database queries?

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