How to run django's test database only in memory?

MySQL supports a storage engine called "MEMORY", which you can configure in your database config (settings.py) as such: 'USER': 'root', # Not used with sqlite3. 'PASSWORD': '', # Not used with sqlite3. 'OPTIONS': { "init_command": "SET storage_engine=MEMORY", } Note that the MEMORY storage engine doesn't support blob / text columns, so if you're using django.db.models.TextField this won't work for you.

I can't answer your main question, but there are a couple of things that you can do to speed things up. Firstly, make sure that your MySQL database is set up to use InnoDB. Then it can use transactions to rollback the state of the db before each test, which in my experience has led to a massive speed-up. You can pass a database init command in your settings.py (Django 1.2 syntax): DATABASES = { 'default': { 'ENGINE':'django.db.backends.mysql', 'HOST':'localhost', 'NAME':'mydb', 'USER':'whoever', 'PASSWORD':'whatever', 'OPTIONS':{"init_command": "SET storage_engine=INNODB" } } } Secondly, you don't need to run the South migrations each time. Set SOUTH_TESTS_MIGRATE = False in your settings.py and the database will be created with plain syncdb, which will be much quicker than running through all the historic migrations.

You can do double tweaking: use transactional tables: initial fixtures state will be set using database rollback after every TestCase. put your database data dir on ramdisk: you will gain much as far as database creation is concerned and also running test will be faster. I'm using both tricks and I'm quite happy. How to set up it for MySQL on Ubuntu: $ sudo service mysql stop $ sudo cp -pRL /var/lib/mysql /dev/shm/mysql $ vim /etc/mysql/my.cnf # datadir = /dev/shm/mysql $ sudo service mysql start Beware, it's just for testing, after reboot your database from memory is lost!