In this diagram there are four data streams (A,B, C, and D) leading to Program X. Each stream includes a Load Set that loads data into one Table instance, and one Program that reads from that Table instance and writes to another Table instance, each of which is a source Table instance for Program X. Load Sets A, B, and C all have an Execution Setup that enables backchain processing. Load Set D does not. The Table instances that are targets of the load do not have the most current possible data, compared to the data in the source system, except for the Table instance in the B stream, which does have the most current possible data. Programs A and B have an Execution Setup that enables backchain processing; Programs C and D do not. None of the Table instances that are targets of the Programs have the most current data, compared to the Programs' source Table instances.