Extending DLR with Labelled Tuples, Projections, Functional Dependencies and Objectification (full version)

TL;DR

This paper extends the description logic DLR to include labelled tuples, projections, dependencies, and objectification, maintaining decidability and computational complexity.

Contribution

It introduces a syntactic condition that ensures decidability in the extended DLR logic with new features.

Findings

Decidability is preserved with the extension

The computational complexity remains unchanged

The extension supports more expressive knowledge representation

Abstract

We introduce an extension of the n-ary description logic DLR to deal with attribute-labelled tuples (generalising the positional notation), with arbitrary projections of relations (inclusion dependencies), generic functional dependencies and with global and local objectification (reifying relations or their projections). We show how a simple syntactic condition on the appearance of projections and functional dependencies in a knowledge base makes the language decidable without increasing the computational complexity of the basic DLR language.