# Fine-Grained Complexity of Regular Path Queries

@inproceedings{Casel2021FineGrainedCO, title={Fine-Grained Complexity of Regular Path Queries}, author={Katrin Casel and Markus L. Schmid}, booktitle={ICDT}, year={2021} }

A regular path query (RPQ) is a regular expression q that returns all node pairs (u, v) from a graph database that are connected by an arbitrary path labelled with a word from L(q). The obvious algorithmic approach to RPQ-evaluation (called PG-approach), i. e., constructing the product graph between an NFA for q and the graph database, is appealing due to its simplicity and also leads to efficient algorithms. However, it is unclear whether the PG-approach is optimal. We address this question by…

## 3 Citations

Conjunctive Regular Path Queries with Capture Groups

- Computer ScienceACM Transactions on Database Systems
- 2022

It is shown that if the expressions have depth 0, or if the the size of the images of capture variables is bounded by a constant, then they can allow arbitrary regular relations, while staying in the same complexity bounds.

THE COMPLEXITY OF REGULAR TRAIL AND SIMPLE PATH QUERIES ON UNDIRECTED GRAPHS

- Mathematics, Computer Science
- 2022

Using techniques from structural graph theory, ranging from the graph minor theorem to group-labeled graphs, several tractable and intractable subclasses of the regular languages are identified.

Knowledge Compilation and Enumeration for Efficient Query Evaluation Algorithms

- Computer Science
- 2021

It is shown that enumeration algorithms could be designed in a modular fashion, and it was shown that circuits serve as an intermediate representation that neatly separate the algorithmic problems of enumeration from the logical problems of reasoning and query evaluation.

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