Oracle NLS parameter queries¶

Oracle NLS parameter queries are SQL commands used to inspect and configure the National Language Support (NLS) environment of an Oracle database session.^[600-developer__database__oracle__oracle-record.md]

Inspecting NLS Settings¶

To view the current NLS configuration, administrators can query the v$nls_parameters view^[600-developer__database__oracle__oracle-record.md]. To verify the specific language and territory settings of the current session, the userenv function can be used^[600-developer__database__oracle__oracle-record.md]:

select userenv('language') from dual;

Configuring Session Parameters¶

NLS parameters can be modified at the session level to resolve display issues, such as garbled text or incorrect date formatting^[600-developer__database__oracle__oracle-record.md].

Date Formatting¶

To prevent garbled or unreadable date output, the date and timestamp formats can be explicitly set^[600-developer__database__oracle__oracle-record.md]:

alter session set nls_date_format='YYYY-MM-DD HH24:MI:SS';
alter session set NLS_TIMESTAMP_FORMAT='YYYY-MM-DD HH24:MI:SS:FF6';

Environment Variables¶

Client-side tools often rely on operating system environment variables to determine NLS behavior^[600-developer__database__oracle__oracle-record.md]. For example, setting the NLS_LANG variable to a specific character set (e.g., AMERICAN_AMERICA.AL32UTF8) before launching a tool like PL/SQL Developer can prevent encoding issues^[600-developer__database__oracle__oracle-record.md].

Related Concepts¶

• [[Oracle Database]]
• [[Character encoding]]

Sources¶

^[600-developer__database__oracle__oracle-record.md]