For example, you might create a mapping that contains multiple transformations. Each transformation performs calculations on the source data. You create a non-reusable Aggregator transformation at the end of the mapping to process the results. When you create a non-reusable transformation, you can drag the ports from one transformation to another transformation in the mapping and create the input ports.

The Developer tool stores the non-reusable Aggregator transformation as metadata that it keeps with the mapping.