Research On Top-k Skyline Query Method In Road Networks

With the popularity of positioning devices and the development of geo-social networks,spatial database query technology has been widely used.The traditional spatial keyword query often finds the target object through two dimensions of space and text.In order to enrich the semantic of spatial keyword query,this paper introduces social relationship information,and proposes Top-k keyword query and Skyline query methods based on social relationship in road network environment.The main research contents are as follows:Firstly,in view of the phenomenon that users in real life will refer to the suggestions of friends or comments of network users in the query process,this paper introduces the social relationship dimension into the Top-k keyword query of road network to improve the query results,and proposes a social relation-based Top-k keyword query method.The index model of spatial component,social relationship component,inverted file component and binding component is designed,and based on the model,the SIG*-TREE index structure is proposed to reduce the distance calculation of road network.According to the similarity between the data object and the query object in three dimensions of space,text and social relationship,the scoring function of the data object is proposed to meet the diverse needs of query users.Theoretical and experimental results show that the proposed method can effectively improve the accuracy and fitness of Top-k keyword query.Furthermore,in order to solve the problem that Top-k keyword queries based on social relations require high prerequisite knowledge of users,this paper proposes a Skyline query method based on social relations in road network environment,and the returned data objects are not dominated by other data objects in three dimensions of space,text and social relations.This paper further expounds the difference between road network distance and Euclidean distance,and proposes three theorems based on road network Voronoi diagram to reduce the data set,which avoids a lot of calculation of road network distance.In addition,since the result set returned by the query also involves non-spatial attributes,two theorems were proposed to further refine the data set to avoid a large number of repeated comparisons of the data set.Based on the theorem and the aggregation score function of data objects,the data set filtering algorithm and the Skyline query algorithm based on social relations are given.Theoretical and experimental results show that the proposed algorithm improves the efficiency and accuracy of Skyline query based on social relations.