sqlplus / as sysdba

shutdown immediate;

STARTUP MOUNT;

ALTER SESSION SET SQL_TRACE=TRUE;

ALTER SYSTEM ENABLE RESTRICTED SESSION;

ALTER SYSTEM SET JOB_QUEUE_PROCESSES=0;

ALTER SYSTEM SET AQ_TM_PROCESSES=0;

ALTER DATABASE OPEN;

ALTER DATABASE character set INTERNAL_USE AL32UTF8;

ALTER SESSION SET SQL_TRACE=FALSE;

shutdown immediate;

startup;

风险分析：执行上述命令，有可能造成数据库中已有数据混乱的情况，所以在进行操作前，

要进行数据库的备份操作；

因为我是刚刚静默安装完成所有省略了备份库

SQL> select userenv('language') from dual;

USERENV('LANGUAGE')

----------------------------------------------------

AMERICAN_AMERICA.AL32UTF8

查看变更记录

SQL> SELECT parameter, value FROM v$nls_parameters WHERE parameter LIKE '%CHARACTERSET';

PARAMETER

----------------------------------------------------------------

VALUE

----------------------------------------------------------------

NLS_CHARACTERSET

AL32UTF8

NLS_NCHAR_CHARACTERSET

AL16UTF16