oracle 10g数据库字符集更改及其出现的异常


		oracle 10g数据库字符集更改及其出现的异常
 
1.更改数据库字符集为GBK
SHUTDOWN IMMEDIATE;  
STARTUP MOUNT EXCLUSIVE;  
ALTER SYSTEM ENABLE RESTRICTED SESSION; 
ALTER SYSTEM SET JOB_QUEUE_PROCESSES=0; 
ALTER SYSTEM SET AQ_TM_PROCESSES=0; 
ALTER DATABASE OPEN; 
ALTER DATABASE NATIONAL CHARACTER SET AL16UTF16; 更改国际字符集
ALTER DATABASE CHARACTER SET ZHS16GBK; 更改本地字符集
SHUTDOWN IMMEDIATE;
STARTUP ;
 
-- ALTER DATABASE NATIONAL CHARACTER SET INTERNAL_USE UTF8;
-- alter database character set internal_use ZHS16GBK ;
-- ALTER DATABASE NATIONAL CHARACTER SET INTERNAL_USE ZHS16GBK;
 
2.如果错误信息，请对照一下信息 
如果提示：
    ORA-12717: Cannot issue ALTER DATABASE NATIONAL CHARACTER SET when NCLOB, NCHAR 
or NVARCHAR2 data exists
则更改使用以下语句:
    ALTER DATABASE NATIONAL CHARACTER SET INTERNAL_USE AL16UTF16;
 
如果提示：
    ORA-12712: new character set must be a superset of old character set
则更改使用以下语句:
    ALTER DATABASE character set INTERNAL_USE ZHS16GBK;
 
如果提示：
    ORA-12721: operation cannot execute when other sessions are active
则更改使用以下语句:
    SHUTDOWN IMMEDIATE;  
    STARTUP MOUNT EXCLUSIVE;
 
如果提示：
    ORA-01109: database not open
则更改使用以下语句:
    ALTER DATABASE OPEN;
 
如果提示：
    ORA-12719: operation requires database is in RESTRICTED mode
则更改使用以下语句:
    ALTER SYSTEM ENABLE RESTRICTED SESSION;