修改oracle字符集将字符编码WE8MSWIN1252修改为AL32UTF8

采用的是默认字符集：WE8MSWIN1252，将字符集修改为：AL32UTF8。

SQL> select userenv('language') from dual;

SIMPLIFIED CHINESE_CHINA.WE8MSWIN1252

SQL> select * from nls_database_parameters where parameter in ('NLS_CHARCTERSET','NLS_NCHAR_CHARACTERSET');

SQL> select* from v$nls_parameters where parameter='NLS_CHARACTERSET';

操作过程如下：

SQL> shutdown immediate

SQL> startup

SQL> alter session set sql_trace=true;

SQL> alter system enable restricted session;

SQL> show parameter job_queue_processes;

SQL> alter system set job_queue_processes=0;

SQL> alter system set aq_tm_processes=0;

SQL> alter database open;

SQL> alter database character set INTERNAL_USE AL32UTF8;

SQL> update props$ set VALUE$='UTF8' where NAME='NLS_NCHAR_CHARACTERSET';

维护完以后需要

SQL>ALTER SYSTEM DISABLE RESTRICTED SESSION;

改变字符集后，原来已有的数据不会改变，只是之后新增的数据会是新的字符集。