1. shutdown immediate;
2. startup mount;
3. alter system enable restricted session;
4. alter system set job_queue_processes=0;
alter system set aq_tm_processes=0;
5. alter database open;
6. alter database character set INTERNAL_USE KO16MSWIN949 ;
7. alter database national character set INTERNAL_USE UTF8;
8. shutdown immediate;
9. startup;
주의 ))
The Oracle9i data dictionary now contains data in CLOB datatypes,
if the database character set is to migrate from single byte
to multiple byte or vice versa via the ALTER DATABASE CHARACTER SET command,
the operation will fail with the error ORA-12716 Cannot ALTER DATABASE CHARACTER SET
when CLOB data exists. The current workaround is to
create a new database using your target database character set and migrate your data
using the export and import utilities.