Universal Relation Views: A Pragmatic Approach
Joachim Biskup, Hans Hermann Brüggemann · Very Large Data Bases · 1983
A universal relation view is a view (external schema) on top of a relational database schema (conceptual schema). It shows the whole database as a single fictitious universal relation. It provides a user-friendly interface where queries can be expressed without navigation, even on the level of relations, as far as possible. We carefully develop the fundamental decisions of our approach: different kinds of users should have a consistent understanding of the view; the underlying database schema should satisfy a new desirable property called unambiguity. Besides unambiguity and the so-called universal scheme assumption our approach does not rely on any further prerequisites.