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Optimization Of Skyline Query Processing Technology On Partially Ordered Domain

Posted on:2021-02-23Degree:MasterType:Thesis
Country:ChinaCandidate:J H WangFull Text:PDF
GTID:2428330602489103Subject:Engineering
Abstract/Summary:PDF Full Text Request
With the development of Internet technology and database technology,and the progress of information collection equipment and technology,Internet data has become increasingly complex and huge in recent years.Therefore,how to help users mine the most valuable information from these massive and complex information has become a hot spot for academic research.As a typical multi-objective decision-making method,skyline query can quickly mine the data resources that users really care about from the complex and huge Internet data according to the needs of users.It plays a very important role in many practical applications.However,the vast majority of skyline algorithms are currently focused on data query in the full-order domain.There are few algorithms for the partial-order domain,and the computational efficiency cannot be well adapted to the increasing needs of users.Therefore,it is a very practical problem to efficiently deal with the skyline query on the partial order domain.In view of the above problems,this paper studies the skyline query problem in the partial order domain,and proposes a method to effectively improve the query efficiency.Specifically,the main contributions of this paper are as follows:(1)It is proposed to introduce the inverted index into the skyline query field.The inverted index sorts the attributes of each preferred dimension from good to bad,reducing a lot of redundant calculations,thereby improving the calculation efficiency;(2)The PSP-B algorithm is proposed to solve the problem that the traditional algorithm scans the entire data set for each calculation.The algorithm establishes an inverted index on each dimension of the data set,and ends the algorithm by quickly finding the end point of the scan through the cyclic scanning strategy,which achieves the purpose of filtering and pruning the data set,and improves the calculation efficiency.(3)Based on the PSP_B algorithm,the PSP-I algorithm is proposed.After mapping the partial order domain to the total order domain and before establishing the inverted index,the entire data set is grouped according to the grouping strategy proposed in this article,and then established within the group Inverted index.It also proposes a whole group filtering strategy.Groups that do not contain skyline result points can be filtered,and the pruning efficiency is further improved on the basis of the basic algorithm.(4)A detailed performance comparison experiment is designed,which proves that the PSP_B and PSP_I algorithms proposed in this paper can effectively deal with the skyline query problem in the partial order domain.And PSP_I algorithm is better than PSP_B algorithm in query efficiency.(5)Finally,a prototype system based on the algorithm proposed in this paper is designed and implemented,which realizes the application value of the algorithm and meets the application needs of query users..
Keywords/Search Tags:skyline query, inverted index, partial order field
PDF Full Text Request
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