On Mon, 04 Apr 2005 11:50:41 +0200, Trygve Reenskaug <trygver at ifi.uio.no>  
wrote:

> ODMG (and Magma) seem to block application evolution by storing the  
> binary objects so that class definitions can't change. It will be  
> difficult to use them in critical applications if this is correct.
>
Depends on the serialization format used. Most OODBMS'es have their own,  
and most of the time it's all handled in Smalltalk anyway, so easy enough  
to adjust. All of the serialization formats I encountered so far have  
calls to Object/Object class that allow you to mess around with the bytes  
stored and retrieved, adding versioning would be reasonably simple.