Data Type Oracle PLSQL

SQL>
SQL> DECLARE
  2    d DATE := SYSTIMESTAMP;
  3    t TIMESTAMP(3) := SYSTIMESTAMP;
  4  BEGIN
  5    dbms_output.put_line('TO_CHAR   ['||TO_CHAR(d,'DD-MON-YY HH24:MI:SS')||']');
  6  END;
  7  /
TO_CHAR   [26-OCT-09 09:03:59]
PL/SQL procedure successfully completed.
SQL>