Querying Best Paths in Graph Databases

TL;DR

This paper introduces a novel approach for querying graph databases that balances expressiveness, clarity, and efficiency, enabling complex path properties to be expressed modularly and answered efficiently.

Contribution

It presents a new formalism with labelling-generating ontologies for expressing complex path properties, achieving efficient query answering in non-deterministic logarithmic space.

Findings

Supports expressing minimal and maximal path properties

Queries can be answered efficiently in non-deterministic logarithmic space

Formalism balances expressiveness, clarity, and computational complexity

Abstract

Querying graph databases has recently received much attention. We propose a new approach to this problem, which balances competing goals of expressive power, language clarity and computational complexity. A distinctive feature of our approach is the ability to express properties of minimal (e.g. shortest) and maximal (e.g. most valuable) paths satisfying given criteria. To express complex properties in a modular way, we introduce labelling-generating ontologies. The resulting formalism is computationally attractive -- queries can be answered in non-deterministic logarithmic space in the size of the database.