Hi,

If you want to modify the obtained result from Data source, you can use response DT. Usually when we Specify response data transform, it will be executed after a response is obtained.

For example, you are using report definition to retrieve employee data. Then you want to set some flag based on their designations, you can use DT to set this type of things.

Most of the times we use Response Data transform in Error handling scenarios. https://community1.pega.com/node/297541

Thanks

Hemalatha