For CDC to work, archive logging must be active for the database. Also, you must create a PowerExchange capture catalog table in the source database. The capture catalog table stores information about the source tables and columns, including Db2 log positioning information.

If you have a source table with user-defined fields or multi-field columns, you can create a data map to manipulate these fields with expressions. For example, you might want to create data map to manipulate packed data in a CHAR column. If you create a data map, you must still create a capture registration and merge the data map with the extraction map that is generated for the capture registration.