A Map statement links a simple source element to a simple target element. The input must be a single value or a constant value. A Map statement can be a child of a Group, Repeating Group, or Option statement.
A Map statement can be a simple mapping between two elements such as a name element in the source and a name element in the target, or it can be complex mapping that uses expressions. For example, you want to map the Id, FirstName, and LastName elements in the source schema to the Name attribute in the target schema. You can configure a Map statement with the input expression