The pgmigrate tool is developed for managing changes in database structure between a project members. It does so by managing so called 'patches'. Small pieces of SQL or Python code which modifies database schema. So far it supports only PostgreSQL.
See GettingStarted for details
PS: So far only for PostgreSQL. Any efforts for adding support of other databases will be appreciated.
PPS: If you are using it in your projects please click I use this at Ohloh.net/projects/pgmigrate project page.
Starting from version 1.2.0 pgmigrate can be easily integrated with Django.