When Oracle GoldenGate is operating only on Windows-based and UNIX-based systems, column mapping and conversion can be performed in the Extract process, or in the Replicat process. To prevent the added overhead of this processing on the Extract process, you can configure the mapping and conversion to be performed on the Replicat process or on an intermediary system.

In the case where there are multiple sources and one target, it might be more efficient to perform the mapping and conversion on the source.