SELECT * FROM mytable ;
WHERE (fieldname1 = Myvalue1 and fieldname2 = Myvalue2) AND ;
(fieldname1 = Myvalue3 and fieldname2 = Myvalue4) AND ;
fiedlname1 = Myvalue5 and fieldname2 = Myvalue6 ;
INTO CURSOR mycursor

IF _TALLY > 0
   MESSAGEBOX("SUCCESS!")
ELSE
  *--DO WATEVER
ENDIF