"unreconcileable" - 1 õppematerjal

IT arhitektuur

encounters an inconsistency that cannot be reconciled) or it is implicitly aborted if a system failure occurs and it does not reach the commit. ·In a flat transaction it is not possible to start a transaction within a transaction. For a transaction to be started there must not be an ongoing transaction. Nested ·The objective of having subtransactions is to be able to set save points within a transaction in order to revert to these save points. ­If an unreconcileable inconsistency is reached, it then becomes possible to undo only a part rather than the whole transaction by aborting only the subtransaction that caused the inconsistency. ­The parent transaction then continous at the point where the aborted subtransactionwas started. ·To start a subtransaction, transactional clients invoke a begin transaction operation from the transaction coordinator during the course of a parent transaction.