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Multidimensional indexing structure for use with linear optimization queriesLinear optimization queries, which usually arise in various decision support and resource planning applications, are queries that retrieve top N data records (where N is an integer greater than zero) which satisfy a specific optimization criterion. The optimization criterion is to either maximize or minimize a linear equation. The coefficients of the linear equation are given at query time. Methods and apparatus are disclosed for constructing, maintaining and utilizing a multidimensional indexing structure of database records to improve the execution speed of linear optimization queries. Database records with numerical attributes are organized into a number of layers and each layer represents a geometric structure called convex hull. Such linear optimization queries are processed by searching from the outer-most layer of this multi-layer indexing structure inwards. At least one record per layer will satisfy the query criterion and the number of layers needed to be searched depends on the spatial distribution of records, the query-issued linear coefficients, and N, the number of records to be returned. When N is small compared to the total size of the database, answering the query typically requires searching only a small fraction of all relevant records, resulting in a tremendous speedup as compared to linearly scanning the entire dataset.
Document ID
20080004989
Acquisition Source
Goddard Space Flight Center
Document Type
Other - Patent
Authors
Bergman, Lawrence David
Castelli, Vittorio
Chang, Yuan-Chi
Li, Chung-Sheng
Smith, John Richard
Date Acquired
August 24, 2013
Publication Date
June 18, 2002
Subject Category
Documentation And Information Science
Report/Patent Number
Patent Number: US-PATENT-6,408,300
Patent Application Number: US-PATENT-APPL-SN-360366
Funding Number(s)
CONTRACT_GRANT: NCC5-305
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Patent
US-PATENT-6,408,300
Patent Application
US-PATENT-APPL-SN-360366
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