oracle忘记system密码

Microsoft Windows XP [版本 5.1.2600]

　　(C) 版权所有 1985-2001 Microsoft Corp.

　　C:\Documents and Settings\Administrator>sqlplus /nolog

　　SQL*Plus: Release 10.1.0.2.0 - Production on 星期六 6月 26 11:08:34 2010

　　Copyright (c) 1982, 2004, Oracle.  All rights reserved.

　　SQL> conn /as sysdba

　　Connected.

　　SQL> alter user system identified by "123456";

　　User altered.

　　SQL> alter user sys identified by "123456";

　　User altered.

　　SQL> alter user system identified by "123456";

　　User altered.

　　SQL> exit

　　Disconnected from Oracle Database 10g Enterprise Edition Release 10.1.0.2.0 - Pr

　　oduction

　　With the Partitioning, OLAP and Data Mining options

　　C:\Documents and Settings\Administrator>sqlplus

　　SQL*Plus: Release 10.1.0.2.0 - Production on 星期六 6月 26 11:11:34 2010

　　Copyright (c) 1982, 2004, Oracle.  All rights reserved.

　　Enter user-name: system

　　Enter password:

　　Connected to:

　　Oracle Database 10g Enterprise Edition Release 10.1.0.2.0 - Production

　　With the Partitioning, OLAP and Data Mining options

　　SQL>  select instance_name from v$instance;

　　INSTANCE_NAME

　　--------------------------------

　　myfirstoracledb