US Patent 7809762 Outage-less database change operation

Techniques to update/change a database without incurring a user outage include receiving a user-specified change command which is then evaluated to determine which portion(s) of the target database will change as a result of the command. Shadow copies of those portions are then created and updated in accordance with the change command. The change command is next applied against the target database and any portion(s) placed in a restricted status because of this action are reset to an un-restricted state. The updated shadow portion(s) are then swapped for the corresponding portion(s) of the target database.