AUTHENTICATION_DATA  
Data being used to authenticate the login user. For X.503 certificate authenticated sessions, this field returns the context of the certificate in HEX2 format.
Note: You can change the return value of the AUTHENTICATION_DATA attribute using the length parameter of the syntax. Values of up to 4000 are accepted. This is the only attribute of USERENV for which Oracle implements such a change.

AUTHENTICATION_TYPE
How the user was authenticated:
DATABASE: username/password authentication
OS: operating system external user authentication
NETWORK: network protocol or ANO authentication
PROXY: OCI proxy connection authentication

BG_JOB_ID  
Job ID of the current session if it was established by an Oracle background process. Null if the session was not established by a background process.

CLIENT_INFO  
Returns up to 64 bytes of user session information that can be stored by an application using the DBMS_APPLICATION_INFO package.

CURRENT_SCHEMA  
Name of the default schema being used in the current schema. This value can be changed during the session with an ALTER SESSION SET CURRENT_SCHEMA statement.

CURRENT_SCHEMAID  
Identifier of the default schema being used in the current session.

CURRENT_USER  
The name of the user whose privilege the current session is under.

CURRENT_USERID  
User ID of the user whose privilege the current session is under.

DB_DOMAIN  
Domain of the database as specified in the DB_DOMAIN initialization parameter.

DB_NAME  
Name of the database as specified in the DB_NAME initialization parameter.

ENTRYID  
The available auditing entry identifier. You cannot use this option in distributed SQL statements. To use this keyword in USERENV, the initialization parameter AUDIT_TRAIL must be set to true.

EXTERNAL_NAME  
External name of the database user. For SSL authenticated sessions using v.503 certificates, this field returns the distinguished name (DN) stored in the user certificate.

FG_JOB_ID  
Job ID of the current session if it was established by a client foreground process. Null if the session was not established by a foreground process.

HOST  
Name of the host machine from which the client has connected.

INSTANCE  
The instance identification number of the current instance.

IP_ADDRESS  
IP address of the machine from which the client is connected.

ISDBA  
TRUE if you are logged on as SYS.

LANG  
The ISO abbreviation for the language name, a shorter form than the existing 'LANGUAGE' parameter.

LANGUAGE
The language and territory currently used by your session, along with the database character set, in the form:language_territory.characterset.

NETWORK_PROTOCOL  
Network protocol being used for communication, as specified in the 'PROTOCOL=protocol' portion of the connect string.

NLS_CALENDAR  
The current calendar of the current session.

NLS_CURRENCY  
The currency of the current session.

NLS_DATE_FORMAT  
The date format for the session.

NLS_DATE_LANGUAGE
The language used for expressing dates.

NLS_SORT  BINARY
or the linguistic sort basis.

NLS_TERRITORY
The territory of the current session.

OS_USER  
Operating system username of the client process that initiated the database session.

PROXY_USER  
Name of the database user who opened the current session on behalf of SESSION_USER.

PROXY_USERID
Identifier of the database user who opened the current session on behalf of SESSION_USER.

SESSION_USER  
Database user name by which the current user is authenticated. This value remains the same throughout the duration of the session.

SESSION_USERID  
Identifier of the database user name by which the current user is authenticated.

SESSIONID  
The auditing session identifier. You cannot use this option in distributed SQL statements.

TERMINAL
The operating system identifier for the client of the current session. In distributed SQL statements, this option returns the identifier for your local session. In a distributed environment, this is supported only for remote SELECT statements, not for remote INSERT, UPDATE, or DELETE operations.
(The return length of this parameter may vary by operating system.)

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