Abstract: A method for applying changes to a standby system is described in which multiple apply tasks or “slaves” are scheduled to changes from redo logs, especially those changes in large transactions, in parallel and as soon as they are encountered in the logs. To foster data convergence, a partial ordering may be imposed on the transactions so that those transactions that actually depend on others are forced to wait on the transactions they are dependent upon commit. To foster read consistency, synchronization points may be periodically established, at which points a read consistent state of the standby database system can be obtained-all without adversely impact the throughput of the system.

Abstract: A lightweight row transfer protocol is described that can be easily handled by thin clients, such as JAVA™ applications using CORBA. The lightweight row transfer protocol serves to reduce bandwidth requirements by applying compression techniques to reduce the number of column lengths in a “result set” of rows that are transmitted from one computer to another.