James:

> Actually, there is another solution. The user can generate offline keys using
> integers, and when going back on line, the application database can return a
> header portion of the key (or session portion). With this scenario, the
> client application controls part of the key and database controls the other.
>
> Header: 123 + Client:124578 = 123124578 !

Although your example may not work for large amount of users/data, it's
certainly a good example of the advantages of evaluating a situation instead
of blindly following a principle !

Daniel