Foundations of an Alternative Approach to Reification in RDF

TL;DR

This paper proposes an extension to RDF and SPARQL that offers an alternative, more usable way to represent statement-level metadata, enhancing data modeling, querying, and interoperability for complex graph structures.

Contribution

It introduces an RDF extension compatible with existing standards that improves handling of statement metadata and supports diverse graph data structures.

Findings

Clarifies methods to understand and map complex graph data to RDF.

Enhances querying capabilities for graph data with link attributes.

Increases flexibility in database design and interoperability.

Abstract

This document defines extensions of the RDF data model and of the SPARQL query language that capture an alternative approach to represent statement-level metadata. While this alternative approach is backwards compatible with RDF reification as defined by the RDF standard, the approach aims to address usability and data management shortcomings of RDF reification. One of the great advantages of the proposed approach is that it clarifies a means to (i) understand sparse matrices, the property graph model, hypergraphs, and other data structures with an emphasis on link attributes, (ii) map such data onto RDF, and (iii) query such data using SPARQL. Further, the proposal greatly expands both the freedom that database designers enjoy when creating physical indexing schemes and query plans for graph data annotated with link attributes and the interoperability of those database solutions.