django-evolution 2.0

A database schema evolution tool for the Django web framework.

Django Evolution is an add-on to the Django web framework that helps manage changes to the database schema.

“But wait, why would I want this? Doesn’t Django have migrations built-in? Isn’t this the same thing?”

Yes, yes it does, and it mostly is. In fact, Django Evolution works comfortably alongside Django’s migrations, helping you get the best out of both.

There are cases where you might want an alternative to migrations:

1. You’re still stuck on Django 1.6 or earlier and need to make changes to your database.

   Django 1.6 is the last version without built-in support for migrations, and there are still codebases out there using it. Django Evolution can help keep upgrades manageable, and make it easier to transition all or part of your codebase to migrations when you finally upgrade.

2. You’re distributing a self-installable web application, possibly used in large enterprises, where you have no control over when people are going to upgrade.

   Django’s migrations assume some level of planning around when changes are made to the schema and when they’re applied to a database. The more changes you make, and the more versions in-between what the user is running and what they upgrade to, the longer the upgrade time.

   If a customer is in control of when they upgrade, they might end up with years of migrations that need to be applied.

   Migrations apply one-by-one, possibly triggering the rebuild of a table many times during an upgrade. Django Evolution, on the other hand, can apply years worth of evolutions at once, optimized to perform as few table changes as possible. This can take days, hours or even seconds off the upgrade time.

What versions of Django are supported?

Django Evolution 2.0 supports Django 1.6 through 3.1.

For older versions of Django, see Django Evolution 0.7.

There’s built-in support for evolving SQLite, Postgres, MySQL, and MariaDB databases.

I can’t imagine anything better… How do I start?

We have a bunch of documentation just for you!

There, you’ll find out how to install it, configure it for your project, generate evolutions, and apply them. Plus, answers to all^W some of your burning questions, like “how do these work with migrations?” and “why is my syncdb/migrate command weird now?”

Who’s using Django Evolution today?

There’s dozens of us! Dozens!

At Beanbag we’re using it in Review Board, our open source code review product, used by thousands of companies world-wide. So we know it works. Review Board predated Django’s migrations by a whole lot of years, and continues to benefit from the optimized upgrade times of evolutions today.