Oracle修改已經建立的數據庫字符集

我是從ZHS16GBK修改成US7ASCII

>sqlplus /nolog

SQL> conn /as sysdba;
Connected.
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup mount;
ORACLE instance started.

Total System Global Area 1071333376 bytes
Fixed Size                  1375792 bytes
Variable Size             612368848 bytes
Database Buffers          452984832 bytes
Redo Buffers                4603904 bytes
Database mounted.
SQL> alter system enable restricted session;

System altered.

SQL> alter system set job_queue_processes=0;

System altered.

SQL> alter system set aq_tm_processes=0;

System altered.

SQL> alter database open;

Database altered.

SQL> alter database character set us7ascii;
alter database character set us7ascii
*
ERROR at line 1:
ORA-12712: new character set must be a superset of old character set

出現如上錯誤，要添加「internal_use」

SQL> alter database character set internal_use us7ascii;

Database altered.

SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup;
ORACLE instance started.

Total System Global Area 1071333376 bytes
Fixed Size                  1375792 bytes
Variable Size             612368848 bytes
Database Buffers          452984832 bytes
Redo Buffers                4603904 bytes
Database mounted.
Database opened.
SQL>

參考文章：

http://www.cnblogs.com/kerrycode/p/3749085.html

http://blog.csdn.net/nsj820/article/details/6571105