select * from v$nls_parameters where parameter='NLS_CHARACTERSET'



                        SQL> SHUTDOWN IMMEDIATE; 
                        SQL> STARTUP MOUNT; 
                        SQL> ALTER SYSTEM ENABLE RESTRICTED SESSION; 
                        SQL> ALTER SYSTEM SET JOB_QUEUE_PROCESSES=0; 
                        SQL> ALTER DATABASE OPEN; 
                        SQL> ALTER DATABASE CHARACTER SET AL32UTF8/ZHS16GBK;
                        SQL> SHUTDOWN IMMEDIATE;
                        SQL> STARTUP;
//修改字符集  UTF-8  ->  GBK