SQL & PL/SQL

Hi,

I wrote a sql script file about 'check_current_date.sql',content as follows,

PROMPT -- Query value of current scn oracle physical standby database

PROMPT

COL current_scn FOR 9999999999999999

COL current_scn NEWVALUE c_scn NOPRINT

SELECT current_scn AS c_scn FROM v$database;

SELECT scn_to_timestamp(&c_scn) FROM DUAL;

and then i execute this sql script file in SQL*Plus, show error:

SYS@standby28>  @check_current_date

-- Query value of current scn oracle physical standby database

SP2-0158: unknown COLUMN option "NEWVALUE"

     C_SCN

----------

1.1746E+10

Enter value for c_scn: exit;

SELECT scn_to_timestamp(exit;) FROM DUAL

                            *

ERROR at line 1:

ORA-00911: invalid character

Please help me,thanks!