HyperBench: A Benchmark and Tool for Hypergraphs and Empirical Findings

1 code implementation • 2 Sep 2020 • Wolfgang Fischl, Georg Gottlob, Davide Mario Longo, Reinhard Pichler

To cope with the intractability of answering Conjunctive Queries (CQs) and solving Constraint Satisfaction Problems (CSPs), several notions of hypergraph decompositions have been proposed -- giving rise to different notions of width, noticeably, plain, generalized, and fractional hypertree width (hw, ghw, and fhw).

HyperBench: A Benchmark and Tool for Hypergraphs and Empirical Findings

1 code implementation • 20 Nov 2018 • Wolfgang Fischl, Georg Gottlob, Davide M. Longo, Reinhard Pichler

To cope with the intractability of answering Conjunctive Queries (CQs) and solving Constraint Satisfaction Problems (CSPs), several notions of hypergraph decompositions have been proposed -- giving rise to different notions of width, noticeably, plain, generalized, and fractional hypertree width (hw, ghw, and fhw).

Databases

General and Fractional Hypertree Decompositions: Hard and Easy Cases

2 code implementations • 3 Nov 2016 • Wolfgang Fischl, Georg Gottlob, Reinhard Pichler

It is known that hw(H) <= k can be checked in polynomial time for fixed k, while checking ghw(H) <= k is NP-complete for any k greater than or equal to 3.

Databases Computational Complexity