When editing a mapping, you may want to view the forward and backward link paths to a particular port. Link paths allow you to see the flow of data from a column in a source, through ports in transformations, to a port in the target.

To view link paths, highlight a port and right-click it. Select the Select Link Path option. You can choose to view either the forward path, backward path, or both. The Designer displays all the connectors in the link path you select.

When displaying both link paths, the Designer traces the flow of data from one column in the source, in and out of each transformation, and into a single port in the target. For unconnected transformations, the Designer does not display a link path. For connected Lookup transformations, the Designer shows each output port dependent upon the input ports involved in the lookup condition. For Custom transformations, the Designer shows that an output port depends on all input ports by default. However, if you define port relationships in a Custom transformation, the Designer shows the dependent ports you define.