DELETE FROM a
FROM         TollData AS a CROSS JOIN
                      a
WHERE     EXISTS
                          (SELECT     1 AS Expr1
                            FROM          TollData
                            WHERE      (CardID = a.CardID) AND (StCardDate = a.starddate) AND (Balance = a.Balance))

delete from a where id not in (select max(id) from a group by CardID,StCardDate ,Balance )