Difference stage: fast path (DataStage)

This section specifies the minimum steps to take to get a Difference stage functioning.

1. Open the stage and expand Properties.
2. Specify the key column. You can repeat this property to specify a composite key. Before and after rows are considered to be the same if they have the same value in the key column or columns.
3. Optionally specify one or more Difference Value columns. This enables you to determine if an after row is an edited version of a before row.
   Note: You can also set the All non-Key columns are Values property to have IBM DataStage treat all columns not defined as keys treated as values.
4. Specify whether the stage will output the changed row or drop it. You can specify this individually for each type of change (copy, delete, edit, or insert).
5. In the Link Ordering section on the Stage tab, specify which of the two links carries the before data set and which carries the after data set.
6. If the two incoming data sets aren't already hash partitioned on the key columns and sorted, set IBM® DataStage® to do this on the Input tab in the partitioning section.