Creating a Context

Syntax#

CREATE [OR REPLACE] CONTEXT namespace USING [schema.]package;
CREATE [OR REPLACE] CONTEXT namespace USING [schema.]package INITIALIZED EXTERNALLY;
CREATE [OR REPLACE] CONTEXT namespace USING [schema.]package INITIALIZED GLOBALLY;
CREATE [OR REPLACE] CONTEXT namespace USING [schema.]package ACCESSED GLOBALLY;

Parameters#

Parameter	Details
`OR REPLACE`	Redefine an existing context namespace
namespace	Name of the context - this is the namespace for calls to `SYS_CONTEXT`
schema	Owner of the package
package	Database package that sets or resets the context attributes. Note: the database package doesn’t have to exist in order to create the context.
`INITIALIZED`	Specify an entity other than Oracle Database that can set the context.
`EXTERNALLY`	Allow the OCI interface to initialize the context.
`GLOBALLY`	Allow the LDAP directory to initialize the context when establishing the session.
`ACCESSED GLOBALLY`	Allow the context to be accessible throughout the entire instance - multiple sessions can share the attribute values as long as they have the same Client ID.
## Remarks#
Oracle documentation (12cR1): https://docs.oracle.com/database/121/SQLRF/statements_5003.htm
## Create a Context

CREATE CONTEXT my_ctx USING my_pkg;

This creates a context that can only be set by routines in the database package my_pkg, e.g.:

CREATE PACKAGE my_pkg AS
  PROCEDURE set_ctx;
END my_pkg;

CREATE PACKAGE BODY my_pkg AS
  PROCEDURE set_ctx IS
  BEGIN
    DBMS_SESSION.set_context('MY_CTX','THE KEY','Value');
    DBMS_SESSION.set_context('MY_CTX','ANOTHER','Bla');
  END set_ctx;
END my_pkg;

Now, if a session does this:

my_pkg.set_ctx;

It can now retrieve the value for the key thus:

SELECT SYS_CONTEXT('MY_CTX','THE KEY') FROM dual;

Value