Creating custom transformations

If the default transforms do not meet your needs, you can also create and add custom transformations to a transformation script on the Editor tab of the Transform page. Transformations can contain attributes and records from your project data set as variables, and can create new attributes to hold the transformed values.

Creating a custom transformation
You can create a custom transformation by writing custom Groovy code in the Transformation Editor. After you save the custom transformation, it is added as one individual execution step to the transformation script.
The Transformation Editor
The Transformation Editor becomes available when you select the Editor tab of the Transform page.
Formats for variables
You can use attributes from your project data set as variables in your transformation scripts. This allows you to pass attributes to transform functions as parameters and perform other operations on them.
Dynamic typing vs. static typing
This topic is provided for reverence only as it explains the differences between dynamic and static typing. Understanding the differences between dynamic and static typing is key to understanding the way in which transformation script errors are handled, and how it is different from the way Groovy handles errors. This will also help you interpret errors created by your transformation script.
Functional and dot notation and function chaining
You must use proper syntax when adding transform functions to your script, or your script won't run properly. You can reference all transform functions using functional notation, as described in this topic.
Script evaluation
Transformation scripts are evaluated top-down on each input row. This means that each transformation in the script is applied in order to the first input row, then again to the second row, and so on. This is illustrated by the following pseudo code:
Extending the transform function library
You can create an external Groovy script that extends the transform function library, and then call the function in a custom transformation. This provides an extension point to the set of default Groovy-based transformation functions provided with BDD.
Exception handling and troubleshooting your scripts
Transform uses a static parser to override some of Groovy's dynamic typing behavior and detect parsing errors, such as undefined variables, when you preview or save your transformations.
Transform logging
If your transformation script fails to commit, you can learn more about the cause of the failure by looking through the Data Processing logs.