Oracle GoldenGate is an asynchronous solution, in a dual active environment systems, conflicts can occur when modifications are made to identical sets of data on separate systems at the same time. Conflicts occur when the timing of simultaneous changes results in one of these out-of-sync conditions:
• A replicated insert attempts to add a row that already exists in the target system.
• The before image of a replicated update does not match the current row in the target system.
• A replicated delete attempts to remove a row that does not exist in the target system.

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