The Change Data Capture (CDC) records created by the Capture Agents contain in addition to before and after images of the Source Datastore content, metadata about the change event that may be unique to the type of datastore. The Replicator Engine provides this metadata either automatically or through options for Streaming targets while the Apply Engine supports a number of special Functions for use in the filtering and transformation logic used to implement business rules:
| Function | Description |
|---|---|
| @BEFORE | Returns the before image of a source field from changed data capture (CDC) records. Replaces functionality of both the CDCBEFORE and MAP_BEFORE functions. |
| CDCEPOCH | Returns Unix Epoch representation of the timestamp associated with a changed data capture (CDC) records only |
| CDCOP | Returns the change operation of the change data capture (CDC) record (generally I, U or D) |
| CDCRAW | Returns the entire unaltered changed data capture (CDC) record from a CDC type datastore |
| CDCSTCK | Returns Storeclock value from changed data capture (CDC) records in a displayable hexadecimal character format of 16 bytes |
| CDCTSTMP | Returns a 26 byte timestamp derived from the Storeclock value in changed data capture (CDC) records |
| CDCTSTMPPK | Returns a 20 byte packed (without punctuation) timestamp derived from the Storeclock value in changed data capture (CDC) records |
| CDCUID | Returns the user ID that changed a source record in changed data capture (CDC) records |
| CDCUOW | Returns the unit-of-work identifier (recovery token) for changed data capture (CDC) records |
| DB2QUAL | Returns the qualifier or schema of the DB2 table for changed data capture (CDC) records |
| DB2TBLNAME | Returns the name of the DB2 table for changed data capture (CDC) records |
| IMSDBDNAME | Returns name of the IMS DBD for changed data capture (CDC) records |
| IMSPGMNAME | Returns the name of the IMS program that made the change to the source data |
| IMSSEGNAME | Returns name of the IMS Segment for changed data capture (CDC) records |
| IMSTRANNAME | Returns name of the IMS transaction used to make the change to the source data |
| RECNAME | Returns the alias of the object associated with the current record of an input datastore |
Note: For information about how to convert from and to the STCK value outside the product, see STORECLOCK.