System for distributed database replicated read with exclusive central server transfer of primary copies

摘要

When an update is made to a data record in a distributed, replicated data processing system, the update is first applied to a primary copy of the data record before being applied to any other copy to ensure that updates are applied in the correct time sequence. Apparatus and a method of operating a distributed data processing system is provided in which responsibility for the primary copy is transferable to whichever processor in the system requires most frequent update access, providing improved performance and availability of data. The primary copy may be partitioned and distributed across the system.