I am trying to have Crystal Reports 11.0 select record if it is unique; not the same as any other where there is this type of list:

J9929 54698
J9929 54625
J9929 54687
J7925 54699

I want to select the J list only if there is one occurrence of this first set of numbers (they are separate fields of numbers for the Js and non-Js); otherwise ignore the entire record. I tried grouping but had trouble.