Typically, only one Extract group is required to efficiently capture from a database. However, depending on the redo (transactional) values, or the data and operation types, you may find that you are required to add one or more Extract group to the configuration.

Similarly, only one Replicat group is typically needed to apply data to a target database if using Replicat in coordinated mode. (See About Coordinated Replicat Mode for more information.) However, even in some cases when using Replicat in coordinated mode, you may be required to use multiple Replicat groups. If you are using Replicat in classic mode and your applications generate a high transaction volume, you probably will need to use parallel Replicat groups.

Because each Oracle GoldenGate component — Extract, data pump, trail, Replicat — is an independent module, you can combine them in ways that suit your needs. You can use multiple trails and parallel Extract and Replicat processes (with or without data pumps) to handle large transaction volume, improve performance, eliminate bottlenecks, reduce latency, or isolate the processing of specific data.

The diagram below shows some of the ways that you can configure Oracle GoldenGate to improve throughput speed and overcome network bandwidth issues.