Repeating the transformation
If your transformation produced invalid records, you may need to return to the original dataset and edit the mapping. Go back to your Workspace and select the dataset and then click on mappings.
Editing a recent mapping
Select the mapping that you need to edit from the list of Recent mappings and the mapping editor will open. Make any changes and preview the results as before. When you have finished making changes, close the mapping editor and return to the Dataset options. Select Transform and run the process again.