--查看oracle数据库字符集：

　　select userenv('language') from dual;

　　查询结果：

　　SIMPLIFIED CHINESE_CHINA.AL32UTF8

　　--修改oracle数据库字符集：（在SQL Plus中）

　　sql> conn / as sysdba;

　　sql> shutdown immediate;

　　database closed.

　　database dismounted.

　　oracle instance shut down.

　　sql> startup mount;

　　oracle instance started.

　　total system global area  135337420 bytes

　　fixed size                          452044 bytes

　　variable size                     109051904 bytes

　　database buffers              25165824 bytes

　　redo buffers                      667648 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 internal_use UTF8

　　sql> shutdown immediate;

　　sql> startup;