--------------注意：如下操作是在RHEL的VNC中執行的，並不是在secureCRT中執行的。------------
--------------原因:若是在secureCRT執行，m3會顯示成：m魯，見如下的截圖,是啥原因我還沒研究--
如下是實驗的過程：
[oracle@lei1 ~]$ export NLS_LANG=AMERICAN_AMERICA.AL32UTF8
[oracle@lei1 ~]$ sqlplus scott/aaaaaa
SQL*Plus: Release 11.2.0.3.0 Production on Sat Jun 20 10:02:14 2015
Copyright (c) 1982, 2011, Oracle. All rights reserved.
Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
SQL> desc test_t1;
Name Null? Type
----------------------------------------- -------- ----------------------------
C1 VARCHAR2(20)
SQL> truncate table test_t1;
Table truncated.
SQL> insert into test_t1 values('m³');
1 row created.
SQL> commit;
Commit complete.
SQL> select * from test_t1;
C1
--------------------
m³
SQL> select property_value from database_properties where property_name='NLS_CHARACTERSET';
PROPERTY_VALUE
--------------------------------------------------------------------------------
AL32UTF8
SQL>
關於Oracle 數據庫存儲數學符號的描述，見如下的mos文章：
NEED TO STORE GREEK, MATH SYMBOLS (Doc ID 1060862.6)
下面全文轉載該文章：
Problem Description:
====================
You would like to store extended Math symbols and the Greek letter Alpha in
the database because your business application requires the presence of those
symbols. You do not know which character set is on the database, but on the
application your NLS_LANG is set to NLS_LANG=American_America.we8iso8859p1 or
AMERICAN_AMERICA.WE8MSWIN1252.
Solution Summary:
=================
Your database was created with the wrong character set. Recreate the database
with the correct character set.
Choice of correct character sets:
EL8ISO8859P7
UTF8
Al32UTF8
Solution Description:
=====================
To find which character set is on the database level, connect internal or as
DBA and run the following query:
SVRMGR> select * from nls_database_parameters;
You probably do not have EL8ISO8859P7, UTF8 or the AL32UTF8 character set
listed for the NLS_CHARACTERSET parameter.
Other character sets do not contain Greek letters or extended Math symbols.
The character set that does is EL8ISO8859P7 or a UNICODE as character set, see:
Note:260893.1 Unicode character sets in the Oracle database
Solution Explanation:
=====================
All character data in an Oracle database is stored using a single character
encoding scheme (character set). The database encoding scheme does not have
to be the same as that used by an application to access database data.
Although, the character set on the database level determines the choice of
characters that can be stored. The database character encoding scheme is
specified when the database is created, before it contains any data, by the
CREATE DATABASE statement. The client-side encoding scheme is specified by
defining the NLS_LANG parameter for a session. Once CREATE'd, a database
encoding scheme cannot be changed without re-creating the database.
