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Editorial Team
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Asked: 2026-06-04T05:58:16+00:00

I want to create a model that will order its children models in the

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I want to create a model that will order its children models in the appropriate way. For instance, a Book has many Chapters, but the Chapters have to be in a specific order.

I assume that I need to put an IntegerField on the Chapter model that specifies the order of the Chapters like the following question suggests: Ordered lists in django

My main issue is that whenever I want to insert a new Chapter in between two existing chapters or reorder them in any way, I have to update (almost) every Chapter in the Book. Is there a way (perhaps in the Django Admin, which I’m using) to avoid having to manually change every index on every Chapter whenever I change the order?

I’m not a big fan of creating a “Linked List” style model, as proposed in the above-linked question, as I am under the impression that’s not good practice for database creation.

What is the “right” way to model this relationship?

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1 Answer

  1. Editorial Team

    The answer you alluded to was probably the best way to handle this efficiently. Probably requiring a raw SQL statement UPDATE Chapter SET order = order + 1 WHERE book_id = <id_for_book> AND order <= <insert_index_location>. For Django 1.1+: You could use F() to write this in a single line as the following, but it might still be O(n) queries under the hood, using transactions.

    Book.objects.get(id=<id_of_book>).chapter_set.filter(order__gt=<place_to_insert>).update(order=F('order')+1)
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