The data warehouse replication is a special replication method. The objective of a data warehouse replication is to be able to recreate the status of a table for any point in time in the past. Data is never deleted, only deactivated. Every change of data can be audited.

To implement this functionality, the output table requires two additional fields:

• An indicator for an active data record (Active_Flag)
• A field containing the timestamp of the last change (DWH_Timestamp)

Behavior:

• INSERT: An INSERT into the output table with Active_Flag = "YES" and the current timestamp in DWH_Timestamp.
• UPDATE: First, the existing active record is deactivated by setting Active_Flag to “NO” and updating DWH_Timestamp with the current timestamp. Then a new record is inserted with the updated field values, Active_Flag = “YES”, and the current timestamp in DWH_Timestamp.
• DELETE: An UPDATE for the output table with Active_Flag = "NO" and the current timestamp in DWH_Timestamp.

In the RDRS Dashboard, double-click the lines connecting the tables to open the Properties of Repository objects dialog:

If certain fields should be cleared during an UPDATE or DELETE, these fields can be specified in this dialog (setting "Fields to be cleared"). An example for this could be the field for ADABAS ISN or the IDMS DBKEY.