human: Given a node-centered hypergraph: <hypergraph>, where nodes represent papers and hyperedges represent sets of papers co-cited by a source paper.

Details of the hypergraph:
Center node: "graph analytics using the vertica relational database"
  Abstract: Graph analytics is becoming increasingly popular, with a deluge of new systems for graph analytics having been proposed in the past few years. These systems often start from the assumption that a new storage or query processing system is needed, in spite of graph data being often collected and stored in a relational database in the first place. In this paper, we study Vertica relational database as a platform for graph analytics. We show that vertex-centric graph analysis can be translated to SQL queries, typically involving table scans and joins, and that modern column-oriented databases are very well suited to running such queries. Specifically, we present an experimental evaluation of the Vertica relational database system on a variety of graph analytics, including iterative analysis, a combination of graph and relational analyses, and more complex 1- hop neighborhood graph analytics, showing that it is competitive to two popular vertex-centric graph analytics systems, namely Giraph and GraphLab.

Connected through hyperedge HE-1 (induced by source paper "livegraph a transactional graph storage system with purely sequential adjacency list scans"):
  with members:
    - "tigergraph a native mpp graph database"
    - "in depth benchmarking of graph database systems with the linked data benchmark council ldbc social network benchmark snb"
    - "weaver a high performance transactional graph database based on refinable timestamps"
    - "rethinking serializable multiversion concurrency control"
    - "high performance concurrency control mechanisms for main memory databases"

Connected through hyperedge HE-2 (induced by source paper "experimental analysis of distributed graph systems"):
  with members:
    - "the ubiquity of large graphs and surprising challenges of graph processing"
    - "tensorflow large scale machine learning on heterogeneous distributed systems"
    - "the gap benchmark suite"
    - "distributed graphlab a framework for machine learning in the cloud"

Connected through hyperedge HE-3 (induced by source paper "extracting and analyzing hidden graphs from relational databases"):
  with members:
    - "snap a general purpose network analysis and graph mining library"
    - "a survey on methods and systems for graph compression"
    - "ringo interactive graph analytics on big memory machines"
    - "pregelix big ger graph analytics on a dataflow engine"
    - "distributed graphlab a framework for machine learning in the cloud"

Connected through hyperedge HE-4 (induced by source paper "empowering in memory relational database engines with native graph processing"):
  with members:
    - "ringo interactive graph analytics on big memory machines"
    - "relational approach for shortest path discovery over large graphs"

Question: Please tell me which class the center node 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)