Data Transformation Engine Map Designer Reference Guide

Map Designer Reference Guide
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Chapter 6 - Map Rules
This chapter introduces map rules. Map rules are used in output cards of a map to
define how output data is built. Map rules are required for output data generation.
If there is no map rule, there is no output data. When no output is desired for a
given data object, a map rule of
=NONE is required.
A map is not complete until each rule cell has a map rule, or appears dimmed (the
map rule is unavailable). Empty rule cells generate a build error when the map is
built.
A map specifies how to generate a particular output data object, or multiple
independent objects, each of a particular type. Each output card has a rule column
in which you enter map rules. Color-coding of map rules provides visual ease of
use in formulating and understanding rules. When color-coding is enabled, syntax
errors in map rules are underlined.
Note Map rules are validated only when that map rule is changed.
Map Rules Overview
Map rules are used to:
♦ Convert an object in the input data from one value to another value in the
output data
♦ Perform conditional logic
♦ Execute another map to produce file with specific contents
A map rule begins with an equal sign (=), followed by an expression that
evaluates to data. The maximum length of a map rule is 32K characters (including
non-printable characters).
Note Non-printable characters are not displayed in the Rule Bar, but display in the rule
cell on the To window as ".