Fine-grained Access Control and Security Policy
Fine-grained access control provides the type of context-sensitive security that used to be implemented in application code or views. But because fine-grained access control is enforced by the database, it is consistently applied across all applications.
Fine-grained access control, introduced in Oracle8i, is implemented by having a security policy associated with a table implement security on that table. The security policy is a program unit that can grant access based on any kind of logical condition. The security policy creates a predicate (a condition added to the WHERE clause to limit data accessed) for any SQL statements issued against the database, which automatically can be used to implement security based on the content of data in the table.