An aggregate mapping maps multiple instances on the source side
to a non-repeatable (scalar) target for some form of aggregation, such as
summation. The following steps show you how to create an aggregate mapping.
Use the drag-and-drop method to create a single aggregate mapping
from an [All] node on the source side to a non-repeatable target.
This is a single operation that is effective for all created
instances at the source. A single one-to-one mapping is created, looping
over all the repeating items in the source message, to the cardinality of
the input.
In the Message Flow Mapping editor Overview, click the Target Value
that you want to edit and then click the box that appears next to this value. The Compose Mapping Expression editor appears, showing the loop.
Use the editor to provide the required information about the mapping.
For example, specify whether the source values
are concatenated or added.
Click OK to close the Compose Mapping Expression
editor.