Oracle 11g Anti-hacker's Cookbook

Using session-based application contexts

The structure of a context consists of a namespace and the associated values it contains. The namespace or name is used for accessing the context's individual attributes, and their associated values held in memory. A namespace can be represented as an associative array with a name-type organization. The initialization of application contexts is performed using a PL/SQL package used in their definition. Generally application contexts are used in VPD implementations to retrieve session information to allow or to block access to certain data.

Next, we will create a locally initialized context type, using a package containing a procedure that initializes a value from the context. The values will be generated ...