Oracle字符集—将数据库服务端字符集WE8MSWIN1252转换成AL32UTF8

注：如果从AL32UTF8字符集的数据库expdp/exp的数据，impdp/imp到WE8MSWIN1252字符集的库，所有的中文字符都是以???的形式存在。即使已经导入后，把WE8MSWIN1252字符的库按照如下改为AL32UTF8也不可以，必须重新impdp/imp导入才ok。

很好用。

1、WE8MSWIN1252转换成AL32UTF8

shutdown immediate;
STARTUP MOUNT;
ALTER SESSION SET SQL_TRACE=TRUE;
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 INTERNAL_USE AL32UTF8;
ALTER SESSION SET SQL_TRACE=FALSE;
shutdown immediate;
startup;
select * from nls_database_parameters;

2、AL32UTF8转换成ZHS16GBK

shutdown immediate;
STARTUP MOUNT;
ALTER SESSION SET SQL_TRACE=TRUE;
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 INTERNAL_USE ZHS16GBK;
--设置INTERNAL_USE指令不对字符集超集进行检查：
ALTER SESSION SET SQL_TRACE=FALSE;
shutdown immediate;
startup;
select * from nls_database_parameters;