You can use PowerCenter to extract change data in real time or from condense files.The extraction process logs information at various points regarding the process status and the contents of various control tables. This enables the overall system to keep track of what has happened and what is required to be extracted at some later request. This is also used to form part of the audit trail.
The extraction process is based on an application name. An application name is created in either of the following situations:
On first use of a extraction process in a PowerCenter task
By using the DTLUAPPL utility
After an application name is used in an extraction process, it preserved as part of the audit trail and additional extraction processes are sensitive to it.