忘记dba用户密码，利用SQLPlus重置dba密码

1. 打开SQL Plus
2. 输入用户名: sys as sysdba
3. 输入口令：可直接回车
4. 连接到:

Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production

With the Partitioning, OLAP, Data Mining and Real Application Testing options

5. alter user sys identified by admin;

用户已更改。

6. conn sys/admin as sysdba;

已连接。

7. alter user system identified by manager;

用户已更改。