Oracle错误：ORA-12899

Oracle错误：ORA-12899

修改过密码之后就能以dba的身份进行修改了,不是dba的话在执行修改命令的时候会提示你权限不足.
开始-->运行-->cmd,之后输入:"sqlplus sys/oracle@192.168.0.1/orcl as SYSDBA"
如果不能正常进入,那就需要你手动输入用户名和密码,进入之后会出现
"SQL>"的提示,
按照下面给出的命令依次执行就可以了,

SQL>SHUTDOWN IMMEDIATE
SQL>STARTUP MOUNT
SQL>ALTER SYSTEM ENABLE RESTRICTED SESSION;
SQL>ALTER SYSTEM SET JOB_QUEUE_PROCESSES=0;
SQL>ALTER SYSTEM SET AQ_TM_PROCESSES=0;
SQL>ALTER DATABASE OPEN;

SQL> ALTER DATABASE CHARACTER SET ZHS16GBK ; ALTER DATABASE CHARACTER SET UTF-8;
ALTER DATABASE CHARACTER SET ZHS16GBK
*ERROR at line 1:
ORA-12712: new character set must be a superset of old character set

报字符集不兼容，此时下INTERNAL_USE指令不对字符集超集进行检查：

SQL>ALTER DATABASE CHARACTER SET INTERNAL_USE ZHS16GBK;
ALTER DATABASE CHARACTER SET INTERNAL_USE UTF8;
SQL>SHUTDOWN IMMEDIATE
SQL>STARTUP