Multi-objective shortest path queries for spatial-textual objects considering preferences
In order to solve the problem of multi-objective shortest path queries of spatial-textual objects considering preference in the road network,an IR tree index structure including attributes is designed;then a restricted directed acyclic graph is constructed by using category constraints and sorting constraints.A local greedy algorithm SALG_SPG supporting attributes is proposed to process the shortest path query.To further improve the query processing efficiency,a global optimal algorithm supporting attributes called SAGO_SPG is proposed.The algorithm uses the threshold and caching mechanism to reduce a large number of invalid and repeated calculations.Finally,the efficiency of the proposed algorithm is analyzed and verified through a comparative experiment with the existing FEBF algorithm.
万方数据
维普
