XMLQuery Processing for Structural Join against XML Data

XMLW3CXPathXQuery

XMLDTD (Document Type Definition)DTD Tree

XML

27 4 join Twig Joins Bruno Koudas twig Structural Joins Chien Numbering Scheme encode Storing and Querying Viglas Dewey

ArticleSection

OIPVolumeNumberSectionSectionSectionNameArticleArticleSectionNameArticleTitleAuthorAuthorKeywordTitleAuthorKeywordTitleAuthorKeyword274Twig JoinsBrunoKoudastwigjoinStructural JoinsChienencodeStoring and QueryingViglasDeweyNumbering SchemeXML

(cont.)DTD TreeOIPVolumeNumberSection*SectionNameArticle*TitleAuthor*DTD Mapping TableKeyword*/OIP/Section/Article/TitleXPath1.-3.-2.1

OIPVolume1Number2Section-3SectionSectionName1Article-2ArticleTitle1Author-2Keyword-3

(cont.)XPathXPathjoin

OIPSection*SectionNameArticle*TitlejoinTwig Joins

Structural Joins /OIP/Section[SectionName = join]/Article/Title

XML

join Twig Joins Bruno Koudas twig Structural Joins Chien Numbering Scheme

(cont.)XQueryXQueryjoinOIPSection*SectionNameArticle*TitlejoinAuthorFor $s in input()/OIP/Section, $a in $s/ArticleLet $sn = $s/SectionNameWhere $sn/text() = 'join'Return $a/Title $a/Author

(cont.)

Twig Joins Bruno

Twig Joins Koudas

Structural Joins Chien

Twig Joins Bruno Koudas

Structural Joins Chien

(cont.)XML()XMLXMLXPathXQueryXMLXQuery

(cont.)ArticleArticleArticleTitleAuthorAuthorTitleAuthorTitleAuthorTwig JoinsBrunoKoudasStructural JoinsChienStoring and QueryingViglasArticle*TitleAuthor*

(cont.) (cont.)DTD TreeXML

XML(Element ID)EidElement TupleEidElement TupleEidSibling Eid

OIPVolumeNumberSectionSectionSectionNameArticleArticleSectionNameArticleTitleAuthorAuthorKeywordTitleAuthorKeywordTitleAuthorKeyword274Twig JoinsBrunoKoudastwigjoinStructural JoinsChienencodeStoring and QueryingViglasDeweyNumbering Scheme

0123(Section)14(Section)45(Article)10(Article)151667 (Author)8(Author)9111213171819Tid | 0 | [1, 2, 3, (-1)] 3 | [4, 5, (14)] 5 | [6, 7, 9, (10)] 7 | [(8)] 8 | [(-1)] 9 | [(-1)]10 | [11, 12, 13, (-1)]12 | [(-1)]13 | [(-1)]14 | [15, 16, (-1)]16 | [17, 18, 19, (-1)]18 | [(-1)]19 | [(-1)]

Element Tuple IndexElement Tuple IndexXMLElement TupleGetTuple(DocID, Tid)GetTuple(0, 3) = [4, 5, (14)]Tid | 0 | [1, 2, 3, (-1)] 3 | [4, 5, (14)] 5 | [6, 7, 9, (10)] 7 | [(8)] 8 | [(-1)] 9 | [(-1)]10 | [11, 12, 13, (-1)]12 | [(-1)]13 | [(-1)]14 | [15, 16, (-1)]16 | [17, 18, 19, (-1)]18 | [(-1)]19 | [(-1)]

Multiple Element IndexMultiple Element IndexEid()GetME(DocID, Eid)GetME(0, 4) = 3GetME(0, 8) = 5012314451015166789111213171819

Pos IndexPos IndexEidXMLEidPI(DocId, Eid)PI(0, 1) = [9, 27]XML927Eid127

Document IndexXMLEidDocIndex(ElementName, Keyword)DocIndex(SectionName, join) = {4}3(Section)4(SectionName)join

XMLDocument IndexEidQueryDecompositionRetrFromDocIndexMETBuildProjectionRetrievalDTDMapping TableDocument IndexPos indexMultiple Element IndexElement Tuple IndexResult XML Doc

(cont.)Supra Gluing Element (SGE)OIPSection*SectionNameArticle*Title/OIP/Section/Article/Title = 1.-3.-2.1/OIP/Section/Section = 1.-3.1SGE/OIP/Section/ = 1.-3SGE

XPath ExampleDecompositionOIPSection*SectionNameArticle*TitlejoinOIPSection*Article*Title1.-3.-2.1OIPSection*SectionNamejoin1.-3.1SGE

XPath Example cont.RetrFromDocIndex & METBuildOIPSection*SectionNamejoin4DocIndex(SectionName, join)Step 1SGEStep 2GetME(0, 4) = 33Step 3

XPath Example cont.ProjectionOIPSection*Article*Title6, 1135SGE/OIP/Section = 1.-3/OIP/Section/Article/Title = 1.-3.-2.1MapPtr = -2, 1GetTuple(0, 3) = [4, 5, (14)]GetTuple(0, 5) = [6, 7, 9, (10)]GetTuple(0, 10) = [11, 12, 13, (-1)]3(Section)14(Section)4(SectionName)15(SectionName)joinencodeStep 2Step 1InitSGE

XPath Example cont.Retrievaltitle6, 11PI(0, 6) = [129, 153]PI(0, 11) = [297, 327]XML DocsTwig Joins

Structural Joins

XQuery ExampleDecompositionOIPSection*SectionNameArticle*TitlejoinOIPSection*Article*TitleOIPSection*SectionNamejoinSGEAuthorOIPSection*Article*Author

XQuery Example cont.RetrFromDocIndex & METBuildOIPSection*SectionNamejoin4DocIndex(SectionName, join)Step 1SGEStep 2GetME(0, 4) = 33Step 3

XQuery Example cont.ProjectionOIPSection*Article*Title33 | [4, 5, (14)]5 | [6, 7, 9, (10)]7 | [(8)]8 | [(-1)]10 | [11, 12, 13, (-1)]12 | [(-1)]14 | [15, 16, (-1)]Author33 53 103 5 63 10 113 5 6 73 5 6 83 10 11 12Section = 1.-3Article = 1.-3.-2Title = 1.-3.-2.1Author = 1.-3.-2.-2

SectionArticleTitleAuthor

XQuery Example cont.RetrievalPI(0, 6) = [129, 153]PI(0, 8) = [164, 185]PI(0, 9) = [196, 218]PI(0, 11) = [297, 327]PI(0, 12) = [338, 359]XML DocsTwig JoinsBrunoKoudasStructural JoinsChien3 5 6 83 5 6 93 10 11 12

SectionArticleTitleAuthor

DTD TreeDTD TreeElement Tuple

(cont.)SGE

Element TupleXMLXMLXMLElement Tuple//()XQuery

Related WorkShu-Yao Chien, Zografoula Vagena, Donghui Zhang, Vassilis J. Tsotras, Carlo Zaniolo, "Efficient Structural Joins on Indexed XML Documents", In Proceedings of the 28th VLDB Conference, Hong Kong, China, 2002Numbering SchemeXMLSibling Pointer

Related Work continueNicolas Bruno, Nick Koudas, Divesh Srivastava, "Holistic Twig Joins: Optimal XML Pattern Matching", In Proceedings of ACM SIGMOD, Madison,Wisconsin, USA, 2002.Numbering SchemeXMLXB-treeParent:[8,20], Child_1:[9, 12], Child_2:[29, 36]

:XML XML XML XMLW3CXPathXQueryXMLDTD TreeXMLDTD Tree XML SectionArticleDTD Mapping Table DTD Tree DTD Mapping TableXPath []XML XPathjoin XPath []XPath SectionNamejoin XPath Title XPathXQueryjoin XQuery []XQuery XPath TitleAuthor TitleAuthor XMLArticleXQuery XML Article []XMLArticle []XML XMLXML XMLXMLXMLXMLXQueryXQuery DTD Tree TitleAuthorDTD TreeArticle [] [] DTD TreeXMLXML XML EidTupleSiblingTuple XML Eid Element Tuple EidXML Element TupleEid3Section 4 Element Tuple4Eid14SectionEid3SectionSibling Eid5Element TupleEid7Author Element TupleElement Tuple IndexElement TupleGetTupleElement TupleDocIDXML DocID0 Eid3Element Tuple GetTuple(0, 3)Multiple Element IndexEidGetME Eid4Eid3Eid8Eid3Multiple Element IndexXMLXML Pos IndexXML PIEid1 PI927 XML927Eid1 Eid1VolumeXML Document IndexEidDocIndexEleNameKeywordEidSectionNamejoin DocIndex(SectionName, join)EidXMLRetrFromDocIndex[] METBuildProjection[]

XML[]DecompositionXML DTD Mapping TableXPath[]DocIndexEid[]METBuildProjectionXML[]RetrievalDTD Tree SGEDTD Tree/OIP/Section/Article/Title/OIP/Section/Section SGE/OIP/SectionXPath XPathprefixSGE1.-3.-2.11.-3.11.-3 /OIP/SectionXPathXPath DTD Mapping TableXPathSGESectionNamejoin DocIndexEid4SGESection GetME 4SectionEid3

[] SGE Element Tuple

[] Element Tuple IndexEid3Tuple 14Sibling [] 14Element TupleTuple2 5Article

[] Element Tuple IndexEid5Tuple Sibling10 Tuple -1Tuple 611 Title

SectionNamejoin DocIndexEid4SGESection GetME 4SectionEid3