When using a mapplet with input ports in a mapping, you connect the mapplet input ports to the mapping pipeline. You can pass data into a mapplet only when it originates from a single active transformation.

For example, in the following figure, the mapplet mpltLookupAndCompare accepts data from two Expression transformations because data from both transformations originate from a single source qualifier. The Source Qualifier SQ_CUSTOMERS is the active transformation providing mapplet source data: