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python - Filtering on many-to-many relations that fulfill a set of criteria

With the following models:

class OrderOperation(models.Model):
    ordered_articles = models.ManyToManyField(Article,
                                              through='orders.OrderedArticle')

class OrderedArticle(models.Model):
    order_operation = models.ForeignKey(OrderOperation)
    article = models.ForeignKey(Article)

articles = ... # some queryset containing multiple articles

If I want to find order operations containing at least one article, this works as expected:

OrderOperation.objects.filter(ordered_articles__in=articles)

However, if I want to find order operations with all the articles in the order, what is the correct way to do it?

OrderOperation.objects.filter(ordered_articles=articles) raises a ProgrammingError: more than one row returned by a subquery used as an expression error (I understand why actually).

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A simple solution:

order_operations = OrderOperation.objects.all()
for article in articles:
    order_operations = order_operations.filter(ordered_articles=article)

It's just one query, but with an inner join per article. For more than a few articles Willem’s more ingenious solution should perform better.


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