SYS_CONTEXT用法

今天需要配合开发写一个触发器审计delete操作，很自然想到SYS_CONTEXT

下面引用sql reference

ACTION Identifies the position in the module (application name) and is set through the
DBMS_APPLICATION_INFO package or OCI.

AUDITED_CURSORID Returns the cursor ID of the SQL that triggered the audit. This parameter is not
valid in a fine-grained auditing environment. If you specify it in such an
environment, then Oracle Database always returns NULL.

AUTHENTICATED_IDENTITY Returns the identity used in authentication. In the list that follows, the type of user
is followed by the value returned:
■ Kerberos-authenticated enterprise user: kerberos principal name
■ Kerberos-authenticated external user : kerberos principal name; same as the
schema name
■ SSL-authenticated enterprise user: the DN in the user's PKI certificate
■ SSL-authenticated external user: the DN in the user's PKI certificate
■ Password-authenticated enterprise user: nickname; same as the login name
■ Password-authenticated database user: the database username; same as the
schema name
■ OS-authenticated external user: the external operating system user name
■ Radius/DCE-authenticated external user: the schema name
■ Proxy with DN : Oracle Internet Directory DN of the client
■ Proxy with certificate: certificate DN of the client
■ Proxy with username: database user name if client is a local database user;
nickname if client is an enterprise user.
■ SYSDBA/SYSOPER using Password File: login name

■ SYSDBA/SYSOPER using OS authentication: operating system user name

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 Database implements such a
change.

AUTHENTICATION_METHOD Returns the method of authentication. In the list that follows, the type of user is
followed by the method returned:
■ Password-authenticated enterprise user, local database user, or
SYSDBA/SYSOPER using Password File; proxy with username using
password: PASSWORD
■ Kerberos-authenticated enterprise or external user: KERBEROS
■ SSL-authenticated enterprise or external user: SSL
■ Radius-authenticated external user: RADIUS
■ OS-authenticated external user or SYSDBA/SYSOPER: OS
■ DCE-authenticated external user: DCE
■ Proxy with certificate, DN, or username without using password: NONE
■ Background process (job queue slave process): JOB
You can use IDENTIFICATION_TYPE to distinguish between external and
enterprise users when the authentication method is Password, Kerberos, or SSL.

BG_JOB_ID Job ID of the current session if it was established by an Oracle Database
background process. Null if the session was not established by a background
process.
CLIENT_IDENTIFIER Returns an identifier that is set by the application through the DBMS_
SESSION.SET_IDENTIFIER procedure, the OCI attribute OCI_ATTR_CLIENT_
IDENTIFIER, or the Java class
Oracle.jdbc.OracleConnection.setClientIdentifier. This attribute is
used by various database components to identify lightweight application users
who authenticate as the same database user.

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_BIND The bind variables for fine-grained auditing.
CURRENT_EDITION_ID The identifier of the current edition.
CURRENT_EDITION_NAME The name of the current edition.
CURRENT_SCHEMA The name of the currently active default schema. This value may change during
the duration of a session through use of an ALTER SESSION SET CURRENT_
SCHEMA statement. This may also change during the duration of a session to reflect
the owner of any active definer's rights object. When used directly in the body of a
view definition, this returns the default schema used when executing the cursor
that is using the view; it does not respect views used in the cursor as being
definer's rights.
Note: Oracle recommends against issuing the SQL statement ALTER SESSION SET
CURRENT_SCHEMA from within a stored PL/SQL unit.

CURRENT_SCHEMAID Identifier of the currently active default schema.
CURRENT_SQL
CURRENT_SQLn
CURRENT_SQL returns the first 4K bytes of the current SQL that triggered the
fine-grained auditing event. The CURRENT_SQLn attributes return subsequent
4K-byte increments, where n can be an integer from 1 to 7, inclusive. CURRENT_
SQL1 returns bytes 4K to 8K; CURRENT_SQL2 returns bytes 8K to 12K, and so
forth. You can specify these attributes only inside the event handler for the
fine-grained auditing feature.
CURRENT_SQL_LENGTH The length of the current SQL statement that triggers fine-grained audit or
row-level security (RLS) policy functions or event handlers. Valid only inside the
function or event handler.
CURRENT_USER The name of the database user whose privileges are currently active. This may
change during the duration of a session to reflect the owner of any active definer's
rights object. When no definer's rights object is active, CURRENT_USER returns the
same value as SESSION_USER. When used directly in the body of a view
definition, this returns the user that is executing the cursor that is using the view; it
does not respect views used in the cursor as being definer's rights.
CURRENT_USERID The identifier of the database user whose privileges are currently active.
DATABASE_ROLE The database role using the SYS_CONTEXT function with the USERENV namespace.
The role is one of the following: PRIMARY, PHYSICAL STANDBY, LOGICAL
STANDBY, SNAPSHOT STANDBY.
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.
DB_UNIQUE_NAME Name of the database as specified in the DB_UNIQUE_NAME initialization
parameter.
ENTRYID The current audit entry number. The audit entryid sequence is shared between
fine-grained audit records and regular audit records. You cannot use this attribute
in distributed SQL statements. The correct auditing entry identifier can be seen
only through an audit handler for standard or fine-grained audit.

ENTERPRISE_IDENTITY Returns the user's enterprise-wide identity:
■ For enterprise users: the Oracle Internet Directory DN.
■ For external users: the external identity (Kerberos principal name, Radius and
DCE schema names, OS user name, Certificate DN).
■ For local users and SYSDBA/SYSOPER logins: NULL.
The value of the attribute differs by proxy method:
■ For a proxy with DN: the Oracle Internet Directory DN of the client
■ For a proxy with certificate: the certificate DN of the client for external users;
the Oracle Internet Directory DN for global users
■ For a proxy with username: the Oracle Internet Directory DN if the client is an
enterprise users; NULL if the client is a local database user.
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.
GLOBAL_CONTEXT_MEMORY Returns the number being used in the System Global Area by the globally accessed
context.
GLOBAL_UID Returns the global user ID from Oracle Internet Directory for Enterprise User
Security (EUS) logins; returns null for all other logins.
HOST Name of the host machine from which the client has connected.

IDENTIFICATION_TYPE Returns the way the user's schema was created in the database. Specifically, it
reflects the IDENTIFIED clause in the CREATE/ALTER USER syntax. In the list that
follows, the syntax used during schema creation is followed by the identification
type returned:
■ IDENTIFIED BY password: LOCAL
■ IDENTIFIED EXTERNALLY: EXTERNAL
■ IDENTIFIED GLOBALLY: GLOBAL SHARED
■ IDENTIFIED GLOBALLY AS DN: GLOBAL PRIVATE
INSTANCE The instance identification number of the current instance.
INSTANCE_NAME The name of the instance.
IP_ADDRESS IP address of the machine from which the client is connected. If the client and
server are on the same machine and the connection uses IPv6 addressing, then ::1
is returned.
ISDBA Returns TRUE if the user has been authenticated as having DBA privileges either
through the operating system or through a password file.
LANG The abbreviated name for the language, 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 this form:
language_territory.characterset
MODULE The application name (module) set through the DBMS_APPLICATION_INFO
package or OCI.
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 user name of the client process that initiated the database
session.
POLICY_INVOKER The invoker of row-level security (RLS) policy functions.
PROXY_ENTERPRISE_
IDENTITY
Returns the Oracle Internet Directory DN when the proxy user is an enterprise
user.
PROXY_GLOBAL_UID Returns the global user ID from Oracle Internet Directory for Enterprise User
Security (EUS) proxy users; returns NULL for all other proxy users.
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.
SERVER_HOST The host name of the machine on which the instance is running.
SERVICE_NAME The name of the service to which a given session is connected.
SESSION_EDITION_ID The identifier of the session edition.
SESSION_EDITION_NAME The name of the session edition.
SESSION_USER The name of the database user at logon. For enterprise users, returns the schema.
For other users, returns the database user name. This value remains the same
throughout the duration of the session.
SESSION_USERID The identifier of the database user at logon.
SESSIONID The auditing session identifier. You cannot use this attribute in distributed SQL
statements.
SID The session ID.
STATEMENTID The auditing statement identifier. STATEMENTID represents the number of SQL
statements audited in a given session. You cannot use this attribute in distributed
SQL statements. The correct auditing statement identifier can be seen only through
an audit handler for standard or fine-grained audit.
TERMINAL The operating system identifier for the client of the current session. In distributed
SQL statements, this attribute 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.)