Update Strategy transformation is used to INSERT, UPDATE, DELETE,or REJECT records based on the defined condition in the mapping. Update Strategy transformation is mostly used when you design mappings for Slowly Changing Dimensions (SCD). When you implement SCDs, you actually decide how you wish to maintain historical data with the current data. We will discuss SCD in Chapter 6, Implementing SCD Using Designer Screen Wizards. When you wish to maintain no history, complete history, or partial history, you can achieve this functionality using either the property defined in the session task or the Update Strategy transformation.
When you use session task, you instruct the Integration service to treat all the records in the same way, that is, Insert, Update or Delete.
When you use Update Strategy transformation in the mapping, the control is no more with the session task. Update Strategy transformation allows you to Insert, Update, Delete, or Reject records based...