We don't have a tutorial on how to do this, but we can take it one step at a time.
First, try just creating a record set that pulls everything from your special table. Then in the same interface, you could see there is a filter drop down list, select the unique column that you don't want to duplicate and then use form variable from the second drop down list and then type the input field name.
let me know once you have the record set created.


