How to use different database engines in Django for testing and production

Question

I'm quite newbie in Django. I have an application in project which is developed with test driven development. In production we use MySQL as database engine, but if I run test with MySQL:

./manage test myapp

Then it absorbs too much time (2-4 mins) to create database, althought tests are quite fast (about a second).

If I use SQLite then tests requires only a few seconds, which is perfect for me. But the problem is that I often need the admin interface with my local database on MySQL.

How to make django to run tests on sqlite and launch runserver with mysql?

Now I use these settings in settings/local.py, but I should comment/uncomment lines to change database depending on what activity I do at the moment.

DATABASES = {
    'default': {
        'ENGINE': 'django.db.backends.sqlite3',  # Use for testing
        'NAME': 'databasename.db3',
        # 'ENGINE': 'django.db.backends.mysql',  # Use if need admin on localserver
        # 'NAME': 'databasename',              
        'USER': 'myuser',                      # Not used with sqlite3.
        'PASSWORD': 'somepassword',                  # Not used with sqlite3.
        'HOST': '',                      # Set to empty string for localhost. Not used with sqlite3.
        'PORT': '',                      # Set to empty string for default. Not used with sqlite3.
        'TEST_CHARSET': "utf8",         #option to make tesing database with utf8
        'TEST_COLLATION': "utf8_general_ci",
    }
}

Answer 1

One option would be to check sys.argv for the test argument in settings.py:

if 'test' in sys.argv:
    DATABASES['default']['ENGINE'] = 'django.db.backends.sqlite3'
    DATABASES['default']['NAME'] = 'databasename.db3'

Though, as a side note: strictly speaking, it is not really a good idea to have different database backends for testing and for development/stage/production. You may encounter database-specific "special" cases, that can cost you a lot of time and headache.