Disk space and processor should be cheap enough so that each developer can run their own instance of the database , with automated assembly under version control. This is necessary so that developers can safely hack into the database in isolation from any other simultaneous hacking.
The caveat is that any changes they make to their private copy are useless to anyone else if they cannot be automatically applied during the build process. Thus, there must be a strong policy that the application code cannot depend on any state of the database, unless this state is represented by versioned versions in the DDL .
. : Evolutionary Database Design .