Oracle 修改字符集

出现ORA-12899,是字符集引起的,中文在UTF-8中占3个字节,ZHS16GBK中占2个字节,而源dmp文件字符集是ZHS16GBK库里倒出来的数据,现在要导入到目标字符集为UTF-8的库里,所以会出现ORA-12899
其实只要修改一下ORACLE 的字符集就可以很好的解决这个问题;

sqlplus /nolog
SQL>conn / as sysdba
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 ZHS16GBK
*ERROR at line 1:
ORA-12712: new character set must be a superset ofold 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：
可以执行下一步 跳转错误操作
SQL>ALTER DATABASE CHARACTER SET INTERNAL_USE ZHS16GBK;
SQL>SHUTDOWN IMMEDIATE
SQL>STARTUP
再次用imp导入，就没有问题了。