We keep the SQL (DDL's) in subversion for creating the schemas. In oracle users that have objects are schemas so you just export/import based on the user.

Oracle’s change in strategy to release a developer-first version of its new database is linked to the company’s plans to defend its market dominance and look at innovative ways to acquire new ...

Using default values on database columns helps to insulate database design issues from application code. Find out how to change a column's default value at a later date using a single command.