What happens if two or more sites change the same data?
If two sites change the same data within the data replication interval, you have an update conflict. The more frequently you propagate your changes (that is, the smaller your replication interval), the fewer update conflicts will occur. Oracle detects update conflicts by comparing the old values for a row from the remote (or propagating) site with the current values at the local (or receiving) site. If they are the same, no conflict has occurred and the new values are applied at the local site. If they are different, a conflict is detected. Oracle attempts to resolve the conflict by using the conflict resolution method that you specified when you first replicated the table. You can choose from among several Oracle-supplied conflict resolution methods (such as, latest timestamp, site priority, additive, etc.) or you can write your own. If you do not supply a method, or if the method that you supply cannot successfully resolve the conflict, Oracle logs the conflicting transaction in an e
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