human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "ontology based data access a study through disjunctive datalog csp and mmsnp"):
  Abstract: Ontology-based data access is concerned with querying incomplete data sources in the presence of domain-specific knowledge provided by an ontology. A central notion in this setting is that of an ontology-mediated query, which is a database query coupled with an ontology. In this paper, we study several classes of ontology-mediated queries, where the database queries are given as some form of conjunctive query and the ontologies are formulated in description logics or other relevant fragments of first-order logic, such as the guarded fragment and the unary-negation fragment. The contributions of the paper are three-fold. First, we characterize the expressive power of ontology-mediated queries in terms of fragments of disjunctive datalog. Second, we establish intimate connections between ontology-mediated queries and constraint satisfaction problems (CSPs) and their logical generalization, MMSNP formulas. Third, we exploit these connections to obtain new results regarding (i) first-order rewritability and datalog-rewritability of ontology-mediated queries, (ii) P/NP dichotomies for ontology-mediated queries, and (iii) the query containment problem for ontology-mediated queries.

Includes members:
  Member "querying the guarded fragment":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "finite open world query answering with number restrictions")
  Member "computing datalog rewritings beyond horn ontologies":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "computing horn rewritings of description logics ontologies")
  Member "exponential lower bounds and separation for query rewriting":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "the lagrangian remainder of taylor s series distinguishes mathcal o f x time complexities to polynomials or not")
  Member "type elimination based reasoning for the description logic shiqbs using decision diagrams and disjunctive datalog":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "worst case optimal query answering for greedy sets of existential rules and their subclasses")
  Member "rewriting ontological queries into small nonrecursive datalog programs":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "polynomial rewritings from expressive description logics with closed predicates to variants of datalog")
  Member "universal structures and the logic of forbidden patterns":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "asnp a tame fragment of existential second order logic")
  Member "a characterisation of first order constraint satisfaction problems":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "rewritability in monadic disjunctive datalog mmsnp and expressive description logics")

Question: Please tell me which class the source paper belongs to. The 40 classes are: cs.NA(Numerical Analysis), cs.MM(Multimedia), cs.LO(Logic in Computer Science), cs.CY(Computers and Society), cs.CR(Cryptography and Security), cs.DC(Distributed, Parallel, and Cluster Computing), cs.HC(Human-Computer Interaction), cs.CE(Computational Engineering, Finance, and Science), cs.NI(Networking and Internet Architecture), cs.CC(Computational Complexity), cs.AI(Artificial Intelligence), cs.MA(Multiagent Systems), cs.GL(General Literature), cs.NE(Neural and Evolutionary Computing), cs.SC(Symbolic Computation), cs.AR(Hardware Architecture), cs.CV(Computer Vision and Pattern Recognition), cs.GR(Graphics), cs.ET(Emerging Technologies), cs.SY(Systems and Control), cs.CG(Computational Geometry), cs.OH(Other Computer Science), cs.PL(Programming Languages), cs.SE(Software Engineering), cs.LG(Machine Learning), cs.SD(Sound), cs.SI(Social and Information Networks), cs.RO(Robotics), cs.IT(Information Theory), cs.PF(Performance), cs.CL(Computation and Language), cs.IR(Information Retrieval), cs.MS(Mathematical Software), cs.FL(Formal Languages and Automata Theory), cs.DS(Data Structures and Algorithms), cs.OS(Operating Systems), cs.GT(Computer Science and Game Theory), cs.DB(Databases), cs.DL(Digital Libraries), cs.DM(Discrete Mathematics). Directly output the class name.

gpt: cs.DB(Databases)