[fauigerzigerk]

I doubt that any DB that stores data physically in a row oriented format doesn't have issues with this particular type of change. But of course there are many other ways to work around that. For instance, you could just create a new table and a view to join the two. Or, if a particular table changes all the time, redesign it to store key value pairs instead. RDBMS can easily be used in a schemaless fashion if needed for particular scenarios.