NLS_LANG=<language>_<territory>.<character set>
Example: export NLS_LANG=AMERICAN_AMERICA.WE8ISO8859P1
Setting NLS_LANG tells Oracle what characterset the client is using so Oracle can do conversion if needed from client’s characterset to the database characterset and setting this parameter on the client does not change the client’s characterset. Setting Language and Territory in NLS_LANG has nothing to do with storing characters in database, it’s controlled by the characterset and of course if the database can store that characterset.
To check session NLS session parameters, note this doesn’t return the characterset set by NLS_LANG
SELECT * FROM NLS_SESSION_PARAMETERS;
SELECT USERENV ('language') FROM DUAL;
To find the NLS_LANG of your database one can run the following SQL:
SQL> SELECT * from NLS_DATABASE_PARAMETERS WHERE parameter IN ( 'NLS_LANGUAGE', 'NLS_TERRITORY', 'NLS_CHARACTERSET');
PARAMETER VALUE
—————————— —————————————-
NLS_LANGUAGE AMERICAN
NLS_TERRITORY AMERICA
NLS_CHARACTERSET WE8MSWIN1252
To get the possible value for language, territory and characterset you can check the view V$NLS_VALID_VALUES.
— parameter – possible values LANGUAGE, TERRITORY, CHARACTERSET
SELECT parameter, value FROM V$NLS_VALID_VALUES;
To change the client language
export NLS_LANG=BELGIUM_.WE8ISO8859P1
To change the client territory
export NLS_LANG=_BELGIUM.WE8ISO8859P1
To change the client characterset
export NLS_LANG=.AL32UTF8
An Oracle Spin by Alex Lima 
particulary useful while importing data…
Dear Asad
Can you help writing what parameters settings are required to enable oracle form6i & DB10g to accept and show URDU language too.
Plea help me iam importing dmp file into oracle 10g, but i can get this message and am not getting data into my system..
plea tel me wat can i do
Export file created by EXPORT:V10.02.01 via conventional path
import done in WE8MSWIN1252 character set and AL16UTF16 NCHAR character set
Import terminated successfully without warnings.
I don’t think the reason why you are not getting data is not related to setting of NLS_DATA, You may want to check the arguments being passed to import.
Thank you very much ;-D
Very usefull !!!
Hi,
11.2.0.7.0 on linux.
My database setting
SQL> SELECT * from NLS_DATABASE_PARAMETERS WHERE parameter IN ( ‘NLS_LANGUAGE’, ‘NLS_TERRITORY’, ‘NLS_CHARACTERSET’);
PARAMETER VALUE
—————————— —————————————-
NLS_LANGUAGE AMERICAN
NLS_TERRITORY AMERICA
NLS_CHARACTERSET WE8MSWIN1252
Mine is a java based web application runs on weblogic.
Please let me know what NLS_LANG I have to configure in the web.config file.
Should it be NLS_LANG=AMERICAN_AMERICA.WE8MSWIN1252
or
NLS_LANG=AMERICAN_AMERICA.UTF8.
Please clear my doubt.
Also for reference please find my OTN question at
https://forums.oracle.com/forums/thread.jspa?threadID=2331980&tstart=0
Thanks in advance
Girish
It would be NLS_LANG=AMERICAN_AMERICA.WE8MSWIN1252
could any one tell how to support burmese character in oracle DB