oracle11g 数据库修改 UTF8字符集

步骤一：执行以下命令

sqlplus "/as sysdba"

conn /as sysdba;

shutdown immediate;

startup mount;

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 UTF8;

shutdown immediate;

startup;

执行alter database character set UTF8; 报错
RROR at line 1:
　　ORA-12712: new character set must be a superset of old character set

ALTER DATABASE character set INTERNAL_USE zhs16gbk;

ALTER SESSION SET SQL_TRACE=FALSE;

shutdown immediate;

STARTUP

select NLS_CHARACTERSET from nls_database_parameters;