Research On Skyline Query Technology In Spatial Database

Spatial query and optimization are difficult points and breakthrough of the related technologies in spatial database, the technology of skyline query has become a hot subject of spatial query and optimization. Now, the technology of skyline query is still at the initial stage, and the technical aspects are not mature, which still has some shortcomings. In this paper, the query and updating technologies of skyline and skycube are analyzed synthetically, and some new methods are proposed based on these, the material contents are as follows.Firstly, the technology of skyline query is studied. The pruning space theorem is presented and demonstrated, and the formal definition is given. Based on these, the algorithm for skyline query based on dynamic window query is proposed. In addition, the correctness of the algorithm is proved and analyzed through examples.Secondly, the technology of skyline updating is studied. The definitions of query region and blank region are presented, and then the skyline updating determinant theorems of inserting and deleting point are presented and demonstrated. Based on these, the Addpoint_Skyline algorithm and Deletepoint_Skyline algorithm are proposed. In addition, the correctness is proved, and the time complexity is computed.Thirdly, the technology of skycube updating is studied. The distinct value theorem is presented and demonstrated, according to this theorem, the distinct value condition is configed. Based on these, the Addpoint_Skycube algorithm and Deletepoint_Skycube algorithm are proposed, then the correctness is proved, and the time complexity is computed.Fourthly, the technology of skycube query in data stream environment is studied. The single point theorem is presented and demonstrated, based on this,the architecture of skycube in the stream environment is proposed, and then every module and its algorithm are analyzed in detail. In addition, the correctness of every algorithm is proved, and the time complexity is computed.Finally, the algorithms in this paper are validated. The algorithm for skyline query based on dynamic window query can return the whole skyline result progressively and it is not nessary to access the whole query space, the updating algorithms can quickly and exactly complete the updating operators of skyline and skycube, and the architecture of skycube in the stream environment can quickly track skycube changes, guarantee the updating of skycube real-time and the results are exact and effective.