In the Orders_Resource mapping, the REST Output transformation contains two groups of output data. The parent group contains customer information and it occurs once for each customer. The child group contains the orders. The orders group is multiple-occurring.

When the REST Output transformation contains more than one group of ports, the Developer tool creates keys to link the groups. The Developer tool creates a primary key in each group. The Developer tool creates a foreign key for each child group. The foreign key in the Orders group contains the customer number for each order.

When you view the ports in the REST Output transformation, you do not see the keys. The keys do not have ports. However, you must link data to the keys to define the key values. To view the keys, show the output mapping in the

Ports

view of the REST Output transformation

Properties

tab. The

Ports

view shows the input ports or the output mapping depending on which option you choose to show.

The following image shows the

Output Mapping

view:

The Developer tool creates the following keys in the output:

Key Name	Description
Key_Orders_Resource	The primary key for the Orders_Resource group.
Key_Orders	The primary key for the Orders group.
FKey_Orders_Resource	The foreign key to link the Orders group to the Orders_Resource group.

You must link input ports to the output keys or the mapping is not valid.