XML数据库查询优化及相关技术研究

《XML数据库查询优化及相关技术研究》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。

1、哈尔滨工程大学博士学位论文XML数据库查询优化及相关技术研究姓名：孙伟申请学位级别：博士专业：计算机应用技术指导教师：刘大昕20060617蜍零滨工程大学薄±学位论文关键谰：XML数据簿；查询优化{XML代数：模式抽取；数据依赖；访问控锘4。．。。；．。。；。。．。型兰鎏鋈譬冀鎏ii：璧鎏茎鍪娄至耋。。；i，．．。；；；。；AbstractWi也tllerapiddevelopmentoftheInternet，alargenumberofW曲dataemergesOnthetnternet．蕊leWebdataformatsasXIvlLdocuments．Itbecomesanimport

2、antresearchtopicofdatabase，howtostoreeffeetivelyandprocesslargeXMLdeeumems，andhowtoretrieveinformationfromthem．TheresearchworkinthisthesisrevolvedaroundqueryoptimizationtechniquesonXMLdatabase，focusingontheresearchoftheXIvlLqueryoptimizationtechnologybasedOnschemaandsemanticinformation．Forthecharact

3、ersofinaccurateschema,巍methodofschemaminingofXMLbasedorlfuzzydecisiontreesisproposed．Basedonanalysisoftheproblemsanddefectsofexistingmethodsofschemamining,theconceptofapproximateschemaisproposed．XMLdocumentsareexpressedonamonadieDatalogprogram．Usinganincrementalclusteringmethod．theapproximateschemai

4、sconstructedbyclusteringobjectswithsimilarincomingandoutgoingedgepatterns．TheperfectschemaoftheclassifiedobjectsbasedOn最辽群decisiontreeisobtained。Itcanovercomethedefeetsoftheschemaminingincludingtwopatternsofexcessanddeficit．AmethodofdiscoveringdatadependencyofXMLbasedonroughsetsisproposed．Datadepend

5、encyisanimportantconceptindatabaseresearch,includedoffunctionaldependencyandmultivatueddependencNThenotionsoffunctionaldependencyandmultivalueddopendencyinXMLaregiven．Thedeterminanttheoretrt$髓X醚乙fimetionaldependeucyandXNfLmuttivatueddependencybasedonindiscemibilityrelationofroughsetsaregiven．Basedon

6、thesetheorems，thealgorithmsofdiscoveringdatadependencyareproposed。AnalgorithmofqueryoptimizationofregularpathexpressionbasedonDTDisproposed．秘毽conceptofextendedregularpathexpressionisdefined。andisusedtoreducetheDTD．Theconceptofenhance-nodeisdefined．Basedontheenhance-nodenotion，twokindsofregularpathex

7、pressionoptimizingprinciplesareproposed，namedpathshonenandpathcomplementing．Usingthesetwokindsofregularpathexpressionoptimizingprinciples，analgorithmispmposcdthatitCanefficientlyoptimizequeryregularpa