修改Oracle數據庫字符集編碼爲utf-8

1.查看當前字符集編碼

   select userenv('language') from dual;

2.修改字符集

   ①在Sql/plus使用dba身份登錄

       conn system as sysdba;

   ②修改爲utf-8

       shutdown immediate;

       startup mount exclusive;

       alert system enable restricted session;

       alert system set job_queue_processes = 0;

       alert system set aq_tm_processes = 0;

       alert database open;

       alert database character set internal_use AL32UTF8;

       shutdown immediate;

       startup;

3.幾個常用命令

給用戶(hr)解鎖：

alter user hr account unlock;

修改用戶(hr)密碼(新密碼爲hr):

alter user hr identified by hr;

授權(emp)表的select權限給用戶(hr):

grant select on emp to hr;

取消授權:

remove select on emp from hr;