SharePlex replication can conveniently be used to maintain a change history target. Another industry jargon for change history is Change Data Capture or CDC. The CDC target maintains historical data on target as opposed to a copy of the source in case of a target in a regular replication. The CDC target is typically used for data mining.
SharePlex gathers change data from source database to populate a change history target by querying redo logs. This is made possible with the advent of supplemental logging. Supplemental logging writes extra information in redo logs which facilitates capturing the change data. At the very least, the minimal database level supplemental logging needs to be enabled at the source. Though supplemental logging can result in extra overhead by way of writing additional info in redo logs, the benefits in terms of change history target far outweigh such costs. In addition, supplemental logging greatly aids regular replication.
Here are some of the salient features of SharePlex change history:
Please refer to SharePlex technical documentation for more details on setting up a CDC replication.