Data Transformation Engine Functions and Expressions Reference Guide

Functions and Expressions Reference Guide
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Chapter 2 - Using Functions
This chapter explains functions used in component rules and map rules. For
additional examples of using functions, see the Introduction to the Design Studio.
Functions
A function is an expression that generates an output by performing a certain
operation on one or more inputs. Most functions can be used in both component
rules and map rules. Those that produce a series can only be used in map rules.
Functions in a Component Rule
For example, the object TotalQty in your data is the sum of all the Qty objects in
your data; in a component rule for TotalQty, you can use the
SUM function to
verify this relationship.
Functions in a Map Rule
Suppose you want to map your data differently according to the presence of a
certain input data object. In your map rule, to check the presence of the data
object, use the function
PRESENT. To create the output according to whether the
input data was present, use the function
IF. Examples of the IF and PRESENT
functions can be found in Chapter 3 - Function Reference.
Syntax of a Function
The following is an example of a function:
FUNCTION ( argument1, argument2, ... argumentn )
When you use a function, substitute the name of a specific function for FUNCTION
and substitute a specific expression for each input argument. Each input argument
is separated by a comma and the set of arguments is surrounded by parentheses.
Function Argument Syntax
Arguments typically have some restrictions on the expression used for that
argument. For example, the input argument to the
INDEX function can only be an