sqlplus /nolog;
SQL>conn / as sysdba;
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 ZHS16GBK;
(这一步一般会出错，所以需要重复执行上面从SHUTDOWN IMMEDIATE开始的所有语句)
SQL> SHUTDOWN IMMEDIATE;
SQL> STARTUP;
