How to view and modify the Oracle encoding format

How to view and modify the Oracle encoding format -- view the Oracle database character set: select userenv ('language') from dual; query result: www.2cto.com SIMPLIFIED CHINESE_CHINA.AL32UTF8 -- modify the oracle database character set: (in SQL Plus) 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 JA16SJIS; SQL> shutdown immediate; SQL> startup;