SYS_CONTEXT function can be use to retrieve information about the Oracle environment.

Example:

Check service Name:

SELECT sys_context('USERENV', 'SERVICE_NAME') FROM DUAL;

Check IP Address:

SELECT sys_context('USERENV', 'IP_ADDRESS') FROM DUAL;

Check OS user:

SELECT sys_context('USERENV', 'OS_USER') FROM DUAL;

Check Date format:

SELECT sys_context('USERENV', 'NLS_DATE_FORMAT') FROM DUAL;

Check Language:

SELECT sys_context('USERENV', 'NLS_DATE_LANGUAGE') FROM DUAL;

Check Session User:

SELECT sys_context('USERENV', 'SESSION_USER') FROM DUAL;

Table: SYS_CONTEXT parameter, 11g Release (11.2) (ORACLE, 2013)

Reference:

ORACLE. (2013). SYS_CONTEXT. Retrieved 04 15, 2014, from http://docs.oracle.com/cd/E11882_01/server.112/e26088/functions184.htm#SQLRF51827