Can you explain the scenario little bit? That would help to formulate the solution. This is obviously can be done using index or Rank functions concatenating with the text that you want.
As per my suggestion, Actual context understanding is needed before we go ahead with any formula.
Please follow the below steps-
1. Create a calculated filed Index-
2. Convert this discrete
3. Put to row self-
4. Go to the format-
In Prefix put KNWA-
Go thru the attachment.
IndexPrefix.twbx 1.2 MB
Thanks a lot I would like to add a text field concatenated with the index "test" + INDEX()
the result would be like :