Oracle’s physical standby data source capability was introduce in Oracle 7.3 to offer data source redundancy. In the future variations of Oracle. This idea has been extend to include assistance for a rational standby database. The improve attribute is call Oracle data source Guard. This principle of a physical alternate site is simple. Keep a copy of the information documents at a 2nd place. Ship the remodel logs to the second website as they are fill up. As well as apply them to the duplicate of the data source.