About Lookup Tables
Lookup tables define a set of key-value (name-value) pairs.
During run time, these key-value pairs are used to translate the passed
in key to the associated value.
Assigning Function(s) to a Mapping Rule
Assign built-in or custom function(s) to a map to convert
or manipulate the data from source node(s) before it populates the
destination node. In addition, the source data for input parameters
can be provided by other functions associated with the mapping rule.