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… 

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