What are the odds. Friday my task was to implement this for our project that uses Django. I learned it all the hard way, even the South trick. The only difference was that we are using MySQL and _django-mysqlpool_.

If almost all solution are using SQLAlchemy components and SQLAlchemy is NOT DBMS-specific, it should be possible to create one package that works for SQLite3, MySQL and Postgres at the same time. In theory, of course. :)