节点与决策模式两段式映射的子图查询算法

针对大规模图集的子图查询问题,给出了一种基于节点与决策模式映射(NDFM)的索引结构——NDFM-Index,并在此索引结构的基础上提出了一种图集的子图查询算法。NDFM-Index利用图中关键节点所携带的结构信息以及邻居的标号分布,与决策模式形成映射,从而不通过枚举直接得到查询图所包含的索引模式,得到更小的候选集。理论与实验的分析结果表明,该算法不但能避免索引筛选过程中对查询图子图的枚举过程,而且能显著地减小候选集尺寸,进而大大降低查询图与候选集之间的子图同构测试次数,提高查询效率。

A subgraph query algorithm based on two-step mapping on vertex to decision feature

To solve the problem of subgraph query processing in large graph databases, the paper gives a two-step node to decision feature mapping (NDFM) indexed structure,named the NDFM-Index, and based on it, proposes a subgraph query processing algorithm. The NDFM-Index uses the mapping between key nodes, with the distribution of neighbors labels, and decision features to get the indexed features which are included by query graph avoiding enumeration method. The results of theoretical analysis and experimental evaluation show that the proposed method not only avoids the enumeration method of getting subgraphs of query graph, but also effectively reduces the subgraph isomorphism tests between the query graph and graphs in candidate answer set in verification stage.