sqlplus /nolog

conn /as sysdba 

shutdown immediate; 

startup mount 

ALTER SYSTEM ENABLE RESTRICTED SESSION; 

ALTER SYSTEM SET JOB_QUEUE_PROCESSES=0; 

ALTER SYSTEM SET AQ_TM_PROCESSES=0; 

alter database open; 

ALTER DATABASE CHARACTER SET ZHS16GBK;

提示我们的字符集：新字符集必须为旧字符集的超集，这时我们可以跳过超集的检查做更改：

ALTER DATABASE character set INTERNAL_USE ZHS16GBK; 

select * from v$nls_parameters; 

shutdown immediate; 

startup 

select * from v$nls_parameters;