1.查看当前数据库SCN
SQL> select current_scn from v$database;


         CURRENT_SCN
--------------------
      15170044180773


SQL> select to_char(15170044180773,'xxxxxxxxxxxxxx') from dual;


TO_CHAR(1517004
---------------
    dcc0d183925


2.使用oradebug查看kcsgscn_


SQL>  oradebug setmypid
Statement processed.
SQL>  oradebug dumpvar sga kcsgscn_
kcslf kcsgscn_ [060019598, 0600195C8) = 0D18398F 00000DCC 00000000 00000000 001627D6 00000000 00000000 00000000 00000000 00000000 60019278 00000000


3.修改为当前SCN加 20000


SQL> select to_char(20000,'xxxxxxxxxxxxxx') from dual;


TO_CHAR(20000,'
---------------
           4e20






SQL>  shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup mount
ORACLE instance started.


Total System Global Area            421777408 bytes
Fixed Size                            2228864 bytes
Variable Size                       343936384 bytes
Database Buffers                     67108864 bytes
Redo Buffers                          8503296 bytes
Database mounted.


SQL>  oradebug setmypid
Statement processed.
SQL> 
SQL>  oradebug dumpvar sga kcsgscn_
kcslf kcsgscn_ [060019598, 0600195C8) = 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 60019278 00000000
SQL> 
SQL> oradebug poke 0x060019598 2 0x4e20
BEFORE: [060019598, 06001959C) = 00000000
AFTER:  [060019598, 06001959C) = 00004E20


SQL> alter database open;


Database altered.


SQL> select current_scn from v$database;


         CURRENT_SCN
--------------------
      15170044265190




看嘛 SCN被成功的推进了  20000