OptimisticConcurrencyControl

The RDB DAS is intended for use in disconnected scenarios. When the DAS returns a graph of SDO DataObjects as the result of a query, there are no locks held on the underlying database and the data is no longer associated with any database connection or transaction. However, although locks are not held, the DAS does employ a mechanism called Optimistic Concurrency Control (OCC) to manage concurrency.

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