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Research On Index And Storage Of Spatio-temporal XML Database

Posted on:2011-06-26Degree:MasterType:Thesis
Country:ChinaCandidate:H Y XuFull Text:PDF
GTID:2178330338476266Subject:Computer application technology
Abstract/Summary:PDF Full Text Request
With the continuous development of spatial database technology and the increasing application of people, the research of time information on spatial data has attracted more and more attention. In this situation, it is inevitable that spatio-temporal database appears. But it brings many difficulties in storage,search and analysis of data in spatio-temporal database system because of the huge volume and unstructured character of spatio-temporal data, especially for searching some data with time confines. With the characters of cross-platform and self-description, XML is adapting to the managing requirements of spatio-temporal data. But after adding time and spatial attribute in XML at the same time, it brings many difficulties in querying the spatio-temporal XML document. In order to improve the query efficiency in temporal XML document, it is necessary to construct index for temporal XML document. However, few researches have been proposed on the issue of indexing spatio-temporal XML, and some relative papers are all about GIS fields.The paper mainly focuses on index research of spatio-temporal XML database. Aiming at the disadvantage of data redundancy in temporal XML document, firstly, a new model that puts time information as prefix of element text is given. Compared to attribute stamped model and element stamped model, this model avoids bringing into new element or attributes text and reduces storage space. Based on the three kind of data models, the elimination of time information redundancy is studied by making use of the time information relationship between elements in the temporal XML documents, as a result of decreasing data redundancy further.Then,in order to prove the validity of spatio-temporal query in XML document, a spatio-temporal query system is built, and some temporal,spatial and spatio-temporal queries was implemented by XPath on this system. Secondly, a spatio-temporal XML index method——CB+-tree is put forward. This index makes use of time information as index keyword, and adds two kinds of lists that help sort index keyword again. At the same time, entity information can be got randomly with the help of entity address and its information length in XML document. Experiment shows that CB+-tree can implement some temporal queries efficiently. At last, considering high requirements of index dynamic in special situation of spatio-temporal XML database update operation,the dynamic updating of CB+-tree is not good, so time information index(TCB+-tree),address index (ACB+-tree) and redundancy storage of document are proposed. Experiment shows that combining redundancy storage method and double index method, dynamic updating effect is improved efficiently.
Keywords/Search Tags:patio-temporal XML, Spatio-temporal XML Index, B+-tree Index, Spatio-temporal Query, Dynamic Update
PDF Full Text Request
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