Stored and Inherited Relations

Abstract

The universally applied Codd's relational model has two constructs: a stored relation, with stored attributes only and a view, only with the inherited ones. In 1992, we have proposed third construct, mixing both types of attributes. Examples showed the idea attractive. No one followed however. We now revisit our proposal. We show that a relational database scheme using also our construct may be more faithful to reality. It may spare the logical navigation or complex value expressions to queries. It may also avoid auxiliary views, often necessary in practice at present. Better late than never, existing DBSs should easily accommodate our proposal, with almost no storage and processing overhead.