Subtle Issues in the Design of a Database Tier Firewall

Applications such as centralized Supply Chain Management permit multiple business partners to host their own customized components at the same site with selective access to a common shared database. If the application software providers are not all trusting of each other, a Database Tier Firewall is necessary. This model assumes that the vocabulary of relational names from the perspective of application developers and users is limited to an abstract schema. Users have views but the view names are unknown to them. Indeed the user may not be aware of the view definitions which change dynamically and reflect access constraints defined and updated by the owner of the data.