Oracle Data Pump can be used to load the historical data from the source database to the target database to ensure the source and target databases are in synch before the data can be replicated. Data Pump is useful when a subset of the database is being replicated. If the full database is being replicated, consider using RMAN or a using standby database, rman duplicate or rman restore and recover to create the target database, although Data Pump can be still be used for copying the full database.
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