Details on ORA_NLS

Details on ORA_NLS:

You can check which NLS setting are valid for this platform by connecting to the database as a DBA and issuing the following command:
SELECT * FROM V$NLS_VALID_VALUES;

If this only returns US7ASCII then ORA_NLSxx was INCORRECTLY set during database startup.

To find out what character set you have, issue the following command:
SELECT * FROM NLS_DATABASE_PARAMETERS;

cd $ORACLE_HOME/nls/data
strings * | grep -i we8mswin1252
where we8mswin1252 is the NLS_CHARACTERSET used.

what is OI_NLS32?
OI_NLS32 is a parameter used by the Oracle Universal Installer and should NOT be altered.

What is the use of this ORA_NLSxx parameter?
ORA_NLSxx is used to indicate where Oracle RDBMS/client software can locate the defintions of Charactersets (used in NLS_LANG or as NLS_CHARACTERSET/NLS_NCHAR_CHARACTERSET), NLS_SORT, NLS_LANGUAGE (or derived/related parameters) or NLS_TERRITORY (or derived/related parameters).
Those definitions are stored in .nlb files who can be found in the ORA_NLSxx directory.

The Priority of NLS Parameters:
select * from NLS_INSTANCE_PARAMETERS;
Priority of NLS Parameter Settings: SESSION >>>> INSTANCE >>>> DATABASE.
NLS instance settings take precedence over NLS database settings, NLS session settings take precedence over NLS instance and NLS database settings.