SELECT F1, F2, F3 ; FROM myTable ; GROUP BY f1 ; HAVING COUNT(*)>1 ; INTO CURSOR mytempIf your "unique" expression is more than one field, just ..
SELECT F1, F2, F3, f1+f2+f3 as f4 ; FROM myTable ; GROUP BY f4 ; HAVING COUNT(*)>1 ; INTO CURSOR mytempHope it is what you want.