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This project is currently unmaintained

You can find alternatives to django-mptt on Django Packages_. Maybe you do not need MPTT, especially when using newer databases. See django-tree-queries for an implementation using recursive Common Table Expressions (CTE). Here's its announcement blog post_.

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django-mptt

Utilities for implementing Modified Preorder Tree Traversal with your Django Models and working with trees of Model instances.

Project home: https://github.com/django-mptt/django-mptt/

Documentation: https://django-mptt.readthedocs.io/

Discussion group: https://groups.google.com/forum/#!forum/django-mptt-dev

What is Modified Preorder Tree Traversal?

MPTT is a technique for storing hierarchical data in a database. The aim is to make retrieval operations very efficient.

The trade-off for this efficiency is that performing inserts and moving items around the tree are more involved, as there's some extra work required to keep the tree structure in a good state at all times.

Here are a few articles about MPTT to whet your appetite and provide details about how the technique itself works:

• Trees in SQL_
• Storing Hierarchical Data in a Database_
• Managing Hierarchical Data in MySQL_

What is django-mptt?

django-mptt is a reusable Django app that aims to make it easy for you to use MPTT with your own Django models.

It takes care of the details of managing a database table as a tree structure and provides tools for working with trees of model instances.

Requirements

• A supported version of Python: https://devguide.python.org/versions/#supported-versions
• A supported version of Django: https://www.djangoproject.com/download/#supported-versions

Feature overview

• Simple registration of models - fields required for tree structure will be

added automatically.

• The tree structure is automatically updated when you create or delete

model instances, or change an instance's parent.

• Each level of the tree is automatically sorted by a field (or fields) of your

choice.

• New model methods are added to each registered model for:

• changing position in the tree
• retrieving ancestors, siblings, descendants
• counting descendants
• other tree-related operations

• A TreeManager manager is added to all registered models. This provides

methods to:

• move nodes around a tree, or into a different tree
• insert a node anywhere in a tree
• rebuild the MPTT fields for the tree (useful when you do bulk updates

outside of Django)

• Form fields_ for tree models.

• Utility functions_ for tree models.

• Template tags and filters_ for rendering trees.

• Admin classes_ for visualizing and modifying trees in Django's administration

interface.