Virtual Private Database (VPD) is a database security feature that is built into an Oracle database server, as opposed to being part of an application that is accessing the data. The user is only allowed to see the data they have been given permission to see.
VPD uses application contexts to provide row-level security and fine-grained access control based on a company's security policies. Application contexts are simply key value pairs that are created in a defined namespace. VPD was first introduced in Oracle8i.