21. Add a fixed value to your results

note the scenario below uses data from the deselect demo data package see docid 5 cozdtg0nwmlmeufrmbz scenario you want to indicate the source of data you're loading into a target data extension by adding a new field that you want to populate with string 'deselect demo data' note this scenario uses the feature custom values, which is available in deselect plus and advanced 1\ input on the selections overview screen, click on new to create a new selection drag data extension deselect demo contacts to the selected data extensions section 2\ output hit the create data extension button, enter a name, eg accounts with source, and press save select the following fields by either double clicking on them or dragging them to the section on the right first name, last name, and email from deselect demo contacts drag email again, and rename it to source click save data extension click on the delete icon next to the email field that's mapped to source we have now created an extra field in our target data extension that we want to populate with 'deselect demo data' this field is not mapped to any fields in the source data extensions now we're going to add the custom value under custom values on the left, click add new value under name, enter demo data and hit next choose type fixed value for field type, choose text for value, enter example text hit save now that the custom value demo data has been created, we can map it to field source by drag and dropping it from custom values to the source mapping field 3\ preview when you click run preview on the preview screen, a results table will be shown with fields first name, last name and email from deselect demo contacts source, populated with 'deselect demo data' note this exact use case is very useful when you're loading data from different sources into the same target data extension using the tabs (append data extensions) functionality