Constructing superviews

Abstract

A method is described for integrating two or more databases into a conceptual "superview", through a set of schema transformations. Such integration may be useful when it is required to produce a unified view of two databases while preserving their physical independence. Each transformation defines a mapping of queries against the superview into the appropriate set of queries against the underlying databases and imposes a constraint that is checked when the query is evaluated. A program that interactively aids the user in constructing the superview and that performs this query transformation is being developed.