Data Transformation Engine Map Designer Reference Guide

Chapter 9 - Functional Map Wizard Referring to the Current Output in a Map Rule
Map Designer Reference Guide
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Referring to the Current Output in a Map Rule
A map rule can include the name of the output object to which it applies. For
example, to use the
INDEX function on LineItem, the map rule on LineItem will
include LineItem. Instead of using the entire object name for LineItem, use the
dollar sign shorthand symbol
$. The dollar sign $ refers to the object to which the
expression applies.
A map rule can also reference other output objects that appear above the map
rule.
In the functional map, you can create an additional input card to represent the
index of the desired item. This is one case in which the type of an input card in a
functional map has been chosen from the output. In fact, any numeric item may
be chosen for that card’s type.
Using a Functional Map to Re-order Data
Use a functional map to arrange data in a different order. For example, you are
growing some flowers and tracking their progress. You have some data for the
measurements you took: height, number of leaves, water intake, and so on.
These ProgressReadings are in no particular order in your input data. For
example, the readings for daisy are scattered throughout the input data.
Shown below is some input data:
Apr-06,Alstromeria,24.14,15,7,32.5
Mar-20,Daisy,15.3,13,12,3.67
May-02,Lily,10.4,7,13,2.5
Apr-22,Daisy,22.4,8,12,2.6
Mar-09,Snapdragon,10.2,7,10,3.2
May-11,Alstromeria,26.8,18,11,3.12
Apr-06,Iris,5.89,5,6,2.7
Apr-10,Daisy,18.4,8,13,4.1
You want to generate an output that consists of reports, one for each flower type.
You want a report for alstromeria, one for daisies, one for snapdragons, and so
on. Use a functional map called MakeReport, to produce one report per flower
type.
To create a report for each flower type, you need to determine the different kinds
of flowers in the input data. To do this, use the
UNIQUE function. The UNIQUE
function looks at all of the values for a given data object and returns the unique
values.