Reachability Queries with Label and Substructure Constraints on Knowledge Graphs

Since knowledge graphs (KGs) describe and model the relationships between entities concepts in real world, reasoning on KGs often correspond to reachability queries with label substructure constraints (LSCR queries). Specifically, for a search path p, LSCR not only require that labels of edges passed by p are certain set, but also claim vertex could satisfy constraint. They much more complex than existing label-constraint (LCR) queries. can be addressed two natural ways (EA-1) an online algorithm (EA-2) combined strategy, best our knowledge. This paper presents optimized algorithms EA-1 EA-2, still inefficient, since their efficiencies highly dominated directions as analyzed this paper. Motivated that, efficient informed strategy KGs, named INSK, lightweight index, local index. An extensive experimental evaluation, both synthetic illustrates INSK efficiently process KGs.