You specify a target load order based on the Source Qualifier transformations in a mapping. If you have multiple Source Qualifier transformations connected to multiple targets, you can designate the order in which the Integration Service loads data into the targets.
If one Source Qualifier transformation provides data for multiple targets, you can enable constraint-based loading in a session to have the Integration Service load data based on target table primary and foreign key relationships.
For example, a mapping contains three pipelines. Each pipeline contains a separate source, source qualifier, transformation, and a flat file target linked together in a mapping. You can configure the target load order for the mapping such that the Integration Service processes each target load order group sequentially.