Data Transformation Engine Map Designer Reference Guide

Chapter 6 - Map Rules A Map Rule is an Expression
Map Designer Reference Guide
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The output CompanyName is defined with an Item Subclass of Text. The
following map rule:
CompanyName = “Pop’s Pizza Co.”
assigns the value of a text literal to the output.
A text literal is text enclosed in double quotes and is interpreted as a text item. A
rule that evaluates to something other than text, for example,
CompanyName =
24 would be invalid.
Tip To view the type properties of a data object in a card, right-click the type in the
input or output card and choose Properties from the context menu. If the
Properties window is shown, select the map rule to update the Properties
window to show the properties of the object.
A map rule on a group type must evaluate to a data object of the same group. For
example, the following map rule on the output group Record must evaluate to the
group type Record:
Record = LOOKUP (Record:Input, Name:Record:Input = “Kathy”)
The map rule is for the group type Record, so it must evaluate to the type
Record. The rule shown above does evaluate to Record because the
LOOKUP
function returns a Record. The rule would be invalid, for example, if it evaluated
to the group Invoice.
Map Rules are Evaluated Independently in Sequential Order
Each map rule is evaluated independently from all other rules. Each output object
with a rule is created independently from the others.
Map rules are evaluated in sequential order. When a map is executed, the first
rule of the first output card is evaluated. Next, the second rule of the first output
card is evaluated, and so on, until the last rule of the first output card. Then, the
first rule of the second output card is evaluated, and so on, to the last rule of the
last output card.