Patent ID: 7523110

Claim:
A method for resolving collisions in an active-active database replication system, the system including a plurality of nodes arranged in a master-slave configuration, each node including a database, wherein changes made at the databases of each node are replicated to the databases at one or more of the other nodes via a master node, and wherein changes can be made at the database of the master node independent of a change request received from a slave node, the method comprising: (a) designating one of the nodes as the master node, the remaining nodes being slave nodes; (b) detecting a collision during data replication between multiple nodes; and (c) resolving the collision by using the following rule: (i) if the collision occurs between the master node and one or more of the slave nodes as a result of a change made at the database of the master node independent of a change request received from a slave node, a change requested to be made to the databases at the one or more slave nodes by the master node is allowed, and a change requested to be made to the database at the master node by the one or more slave nodes is disallowed.