Temporal Graph Functional Dependencies [Extended Version]

Abstract

We propose a class of functional dependencies for temporal graphs, called TGFDs. TGFDs capture both attribute-value dependencies and topological structures of entities over a valid period of time in a temporal graph. It subsumes graph functional dependencies (GFDs) and conditional functional dependencies (CFDs) as a special case. We study the foundations of TGFDs including satisfiability, implication and validation. We show that the satisfiability and validation problems are coNP-complete and the implication problem is NP-complete. We also present an axiomatization of TGFDs and provide the proof of the soundness and completeness of the axiomatization.

Reasoning on Property Graphs with Graph Generating Dependencies

“…Other types of dependencies recently proposed for property graphs include Temporal Graph Functional Dependencies (TGFDs) [25] and Graph Probabilistic Dependencies (GPDs) [26]. The main idea of TGFDs is to extend GFDs by adding a time constraint.…”

Discovery of Keys for Graphs [Extended Version]

“…The expansion of graph databases has lead to the study of integrity constraints over graphs, including functional dependencies [17,6], keys [14] and their ontological invariant [26]. The theoretical foundation of these constraints have been studied and there has been a wide application of key constraints for deduplication, citation of digital objects, data validation and knowledge base expansion [13,22].…”