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The Priority of NLS Parameters Explained (Where To Define NLS Parameters) (Doc ID 241047.1)

Last updated on AUGUST 09, 2021

Applies to:

Oracle Database Cloud Schema Service - Version N/A and later
Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle Database Cloud Exadata Service - Version N/A and later
Oracle Database Backup Service - Version N/A and later
Information in this document applies to any platform.


This note explains the order in which NLS parameters are taken into account in the database client/server model using a standard client connection. i.e NLS_LANG


This is relevant from Oracle 8.0 Onward and intended for Oracle DBAs and support analysts.


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In this Document
 A) The Session Parameters - NLS_SESSION_PARAMETERS.
 A1) Using alter session .
 A2) Using NLS_LANG on the client side
 A2a) NLS_LANG is specified with only the <NLS_Territory> part.
 A2b) NLS_LANG is specified with only the <NLS_Language> part
 A2c) NLS_LANG is specified with only the <clients characterset>
 A2d) Setting other NLS parameters on the client side
 A2e) Defaults values for settings in NLS_SESSION_PARAMETERS:
 A2f) If NLS_LANG is not set
 A3) Other things who are good to know:
 B) The Instance Parameters - NLS_INSTANCE_PARAMETERS.
 C) The Database Parameters - NLS_DATABASE_PARAMETERS.
 D) Other views containing NLS information:
 D1) sys.props$
 D2) v$nls_parameters
 D3) userenv language / sys_context language
 D4) userenv ('lang')
 D5) show parameter NLS%
 D6) v$parameter
 D7) v$system_parameter
 D8) database_properties
 E) Other parameters with "NLS" in the name:
 F) What are valid values to use for NLS parameters?
 G) I'm the dba and have been asked to set a NLS parameter ( NLS_DATE_FORMAT etc) "on database" level.
 H) NLS parameters when using JDBC

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