Natural Stored and Inherited Relations

Abstract

A stored and inherited relation (SIR) is a 1NF stored relation (SR) enlarged with inherited attributes (IAs). We show that one may consider a usual scheme of an SR R with foreign keys as implicitly defining a natural SIR R. IAs do not introduce normalization anomalies, while a usual select-project-join query to SR R with foreign keys becomes select-project only towards natural SIR R. Such queries become thus logical navigation free (LNF), without any additional data definition work, unlike at present. We show how the usual SR schemes provide for natural SIRs. We show also that making a popular DBS SIR-enabled should be simple. Pre-existing relations with foreign keys could be trivially converted to SIRs, preserving existing applications, while providing for LNF queries for new ones. We postulate every major DBS becoming SIR-enabled “better sooner than later”.