EFTA: a database retrieval algebra for feature-terms
Identifieur interne : 001257 ( Istex/Corpus ); précédent : 001256; suivant : 001258EFTA: a database retrieval algebra for feature-terms
Auteurs : Thomas Ludwig ; Bernd WalterSource :
- Data & Knowledge Engineering [ 0169-023X ] ; 1991.
Abstract
We define a data-model based on the notation of a feature-term. A Feature-Term Algebra (FTA) for database-retrieval of feature-terms is presented. FTA is comparable to other attempts to extend or modify Relational Algebra to cope with complex objects and set-valued attributes etc., but extends these proposals to an open-world-assumption for the processing of incomplete knowledge. Since we want to define the algebra as an intermediate language for the compilation of feature-logic database-queries, we augment it by a closure-operator to be able to compile recursive queries. Formal semantics of this Extended Feature-Term Algebra (EFTA) are given, its expressive power is investigated, and the algebra is discussed in the context of related work.
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DOI: 10.1016/0169-023X(91)90019-T
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Box 3825, D 5500 Trier, Germany</mods:affiliation></affiliation></author></titleStmt><publicationStmt><idno type="wicri:source">ISTEX</idno><idno type="RBID">ISTEX:83D907268DC7AC753A5F773B98B4C1593D03C087</idno><date when="1991" year="1991">1991</date><idno type="doi">10.1016/0169-023X(91)90019-T</idno><idno type="url">https://api.istex.fr/document/83D907268DC7AC753A5F773B98B4C1593D03C087/fulltext/pdf</idno><idno type="wicri:Area/Istex/Corpus">001257</idno><idno type="wicri:explorRef" wicri:stream="Istex" wicri:step="Corpus" wicri:corpus="ISTEX">001257</idno></publicationStmt><sourceDesc><biblStruct><analytic><title level="a">EFTA: a database retrieval algebra for feature-terms</title><author><name sortKey="Ludwig, Thomas" sort="Ludwig, Thomas" uniqKey="Ludwig T" first="Thomas" last="Ludwig">Thomas Ludwig</name><affiliation><mods:affiliation>Fachbereich 4, University of Trier, P.O. Box 3825, D 5500 Trier, Germany</mods:affiliation></affiliation></author><author><name sortKey="Walter, Bernd" sort="Walter, Bernd" uniqKey="Walter B" first="Bernd" last="Walter">Bernd Walter</name><affiliation><mods:affiliation>Fachbereich 4, University of Trier, P.O. 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A Feature-Term Algebra (FTA) for database-retrieval of feature-terms is presented. FTA is comparable to other attempts to extend or modify Relational Algebra to cope with complex objects and set-valued attributes etc., but extends these proposals to an open-world-assumption for the processing of incomplete knowledge. Since we want to define the algebra as an intermediate language for the compilation of feature-logic database-queries, we augment it by a closure-operator to be able to compile recursive queries. Formal semantics of this Extended Feature-Term Algebra (EFTA) are given, its expressive power is investigated, and the algebra is discussed in the context of related work.</div></front></TEI><istex><corpusName>elsevier</corpusName><author><json:item><name>Thomas Ludwig</name><affiliations><json:string>Fachbereich 4, University of Trier, P.O. 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FTA is comparable to other attempts to extend or modify Relational Algebra to cope with complex objects and set-valued attributes etc., but extends these proposals to an open-world-assumption for the processing of incomplete knowledge. Since we want to define the algebra as an intermediate language for the compilation of feature-logic database-queries, we augment it by a closure-operator to be able to compile recursive queries. Formal semantics of this Extended Feature-Term Algebra (EFTA) are given, its expressive power is investigated, and the algebra is discussed in the context of related work.</abstract><qualityIndicators><score>6.332</score><pdfVersion>1.2</pdfVersion><pdfPageSize>533 x 756 pts</pdfPageSize><refBibsNative>true</refBibsNative><keywordCount>4</keywordCount><abstractCharCount>750</abstractCharCount><pdfWordCount>10643</pdfWordCount><pdfCharCount>51958</pdfCharCount><pdfPageCount>25</pdfPageCount><abstractWordCount>111</abstractWordCount></qualityIndicators><title>EFTA: a database retrieval algebra for feature-terms</title><pii><json:string>0169-023X(91)90019-T</json:string></pii><refBibs><json:item><author><json:item><name>S. Abiteboul</name></json:item><json:item><name>N. 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Degree in Computer Science from the Technical University of Darmstadt in 1987. He now works as a research assistant in the Database Research Group of the University of Trier, where he is currently completing his Ph.D. thesis. His research interests are languages, architectures, and query processing for deductive database systems.</note><affiliation>Thomas Ludwig received his M.Sc. Degree in Computer Science from the Technical University of Darmstadt in 1987. He now works as a research assistant in the Database Research Group of the University of Trier, where he is currently completing his Ph.D. thesis. His research interests are languages, architectures, and query processing for deductive database systems.</affiliation><affiliation>Fachbereich 4, University of Trier, P.O. Box 3825, D 5500 Trier, Germany</affiliation></author><author xml:id="author-2"><persName><forename type="first">Bernd</forename><surname>Walter</surname></persName><note type="biography">The work reported here was carried out within the LILOG-project of IBM Germany.</note><affiliation>The work reported here was carried out within the LILOG-project of IBM Germany.</affiliation><affiliation>Fachbereich 4, University of Trier, P.O. Box 3825, D 5500 Trier, Germany</affiliation></author></analytic><monogr><title level="j">Data & Knowledge Engineering</title><title level="j" type="abbrev">DATAK</title><idno type="pISSN">0169-023X</idno><idno type="PII">S0169-023X(00)X0079-1</idno><imprint><publisher>ELSEVIER</publisher><date type="published" when="1991"></date><biblScope unit="volume">6</biblScope><biblScope unit="issue">2</biblScope><biblScope unit="page" from="125">125</biblScope><biblScope unit="page" to="149">149</biblScope></imprint></monogr><idno type="istex">83D907268DC7AC753A5F773B98B4C1593D03C087</idno><idno type="DOI">10.1016/0169-023X(91)90019-T</idno><idno type="PII">0169-023X(91)90019-T</idno></biblStruct></sourceDesc></fileDesc><profileDesc><creation><date>1991</date></creation><langUsage><language ident="en">en</language></langUsage><abstract xml:lang="en"><p>We define a data-model based on the notation of a feature-term. A Feature-Term Algebra (FTA) for database-retrieval of feature-terms is presented. FTA is comparable to other attempts to extend or modify Relational Algebra to cope with complex objects and set-valued attributes etc., but extends these proposals to an open-world-assumption for the processing of incomplete knowledge. Since we want to define the algebra as an intermediate language for the compilation of feature-logic database-queries, we augment it by a closure-operator to be able to compile recursive queries. Formal semantics of this Extended Feature-Term Algebra (EFTA) are given, its expressive power is investigated, and the algebra is discussed in the context of related work.</p></abstract><textClass><keywords scheme="keyword"><list><head>Keywords</head><item><term>Deductive database</term></item><item><term>Complex object algebra</term></item><item><term>Open world assumption</term></item><item><term>Recursive queries</term></item></list></keywords></textClass></profileDesc><revisionDesc><change when="1991">Published</change></revisionDesc></teiHeader></istex:fulltextTEI><json:item><extension>txt</extension><original>false</original><mimetype>text/plain</mimetype><uri>https://api.istex.fr/document/83D907268DC7AC753A5F773B98B4C1593D03C087/fulltext/txt</uri></json:item></fulltext><metadata><istex:metadataXml wicri:clean="Elsevier, elements deleted: tail"><istex:xmlDeclaration>version="1.0" encoding="utf-8"</istex:xmlDeclaration><istex:docType PUBLIC="-//ES//DTD journal article DTD version 4.5.2//EN//XML" URI="art452.dtd" name="istex:docType"></istex:docType><istex:document><converted-article version="4.5.2" docsubtype="fla"><item-info><jid>DATAK</jid><aid>9190019T</aid><ce:pii>0169-023X(91)90019-T</ce:pii><ce:doi>10.1016/0169-023X(91)90019-T</ce:doi><ce:copyright type="unknown" year="1991"></ce:copyright></item-info><head><ce:title>EFTA: a database retrieval algebra for feature-terms</ce:title><ce:author-group><ce:author><ce:given-name>Thomas</ce:given-name><ce:surname>Ludwig</ce:surname><ce:cross-ref refid="FN2"><ce:sup>1</ce:sup></ce:cross-ref></ce:author><ce:author><ce:given-name>Bernd</ce:given-name><ce:surname>Walter</ce:surname><ce:cross-ref refid="FN1"><ce:sup>∗</ce:sup></ce:cross-ref><ce:cross-ref refid="FN3"><ce:sup>2</ce:sup></ce:cross-ref></ce:author><ce:affiliation><ce:textfn>Fachbereich 4, University of Trier, P.O. Box 3825, D 5500 Trier, Germany</ce:textfn></ce:affiliation><ce:footnote id="FN2"><ce:label>1</ce:label><ce:note-para><ce:bold>Thomas Ludwig</ce:bold> received his M.Sc. Degree in Computer Science from the Technical University of Darmstadt in 1987. He now works as a research assistant in the Database Research Group of the University of Trier, where he is currently completing his Ph.D. thesis. His research interests are languages, architectures, and query processing for deductive database systems.</ce:note-para></ce:footnote><ce:footnote id="FN1"><ce:label>∗</ce:label><ce:note-para>The work reported here was carried out within the LILOG-project of IBM Germany.</ce:note-para></ce:footnote><ce:footnote id="FN3"><ce:label>2</ce:label><ce:note-para><ce:bold>Bernd Walter</ce:bold> received his M.Sc. degree (Dipl.-Inform.) and the Ph.D. degree (Dr.rer.nat.) in Computer Science from University of Stuttgart, Germany, in 1977 and 1982, respectively. He is currently a Professor of Computer Science at the University of Trier, Germany, where he is the head of the Database Research Group. From 1986 to 1989 he was a Professor for Computer Science at the Technical University of Aachen (RWTH). His research interests include database system architecture, deductive database systems, and distributed systems.</ce:note-para></ce:footnote></ce:author-group><ce:abstract><ce:section-title>Abstract</ce:section-title><ce:abstract-sec><ce:simple-para>We define a data-model based on the notation of a feature-term. A Feature-Term Algebra (<ce:italic>FTA</ce:italic>) for database-retrieval of feature-terms is presented. <ce:italic>FTA</ce:italic> is comparable to other attempts to extend or modify Relational Algebra to cope with complex objects and set-valued attributes etc., but extends these proposals to an open-world-assumption for the processing of incomplete knowledge. Since we want to define the algebra as an intermediate language for the compilation of feature-logic database-queries, we augment it by a closure-operator to be able to compile recursive queries. Formal semantics of this Extended Feature-Term Algebra (<ce:italic>EFTA</ce:italic>) are given, its expressive power is investigated, and the algebra is discussed in the context of related work.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:keywords><ce:section-title>Keywords</ce:section-title><ce:keyword><ce:text>Deductive database</ce:text></ce:keyword><ce:keyword><ce:text>Complex object algebra</ce:text></ce:keyword><ce:keyword><ce:text>Open world assumption</ce:text></ce:keyword><ce:keyword><ce:text>Recursive queries</ce:text></ce:keyword></ce:keywords></head></converted-article></istex:document></istex:metadataXml><mods version="3.6"><titleInfo><title>EFTA: a database retrieval algebra for feature-terms</title></titleInfo><titleInfo type="alternative" contentType="CDATA"><title>EFTA: a database retrieval algebra for feature-terms</title></titleInfo><name type="personal"><namePart type="given">Thomas</namePart><namePart type="family">Ludwig</namePart><affiliation>Fachbereich 4, University of Trier, P.O. Box 3825, D 5500 Trier, Germany</affiliation><description>Thomas Ludwig received his M.Sc. Degree in Computer Science from the Technical University of Darmstadt in 1987. He now works as a research assistant in the Database Research Group of the University of Trier, where he is currently completing his Ph.D. thesis. His research interests are languages, architectures, and query processing for deductive database systems.</description><role><roleTerm type="text">author</roleTerm></role></name><name type="personal"><namePart type="given">Bernd</namePart><namePart type="family">Walter</namePart><affiliation>Fachbereich 4, University of Trier, P.O. Box 3825, D 5500 Trier, Germany</affiliation><description>The work reported here was carried out within the LILOG-project of IBM Germany.</description><role><roleTerm type="text">author</roleTerm></role></name><typeOfResource>text</typeOfResource><genre type="research-article" displayLabel="Full-length article"></genre><originInfo><publisher>ELSEVIER</publisher><dateIssued encoding="w3cdtf">1991</dateIssued><copyrightDate encoding="w3cdtf">1991</copyrightDate></originInfo><language><languageTerm type="code" authority="iso639-2b">eng</languageTerm><languageTerm type="code" authority="rfc3066">en</languageTerm></language><physicalDescription><internetMediaType>text/html</internetMediaType></physicalDescription><abstract lang="en">We define a data-model based on the notation of a feature-term. A Feature-Term Algebra (FTA) for database-retrieval of feature-terms is presented. FTA is comparable to other attempts to extend or modify Relational Algebra to cope with complex objects and set-valued attributes etc., but extends these proposals to an open-world-assumption for the processing of incomplete knowledge. Since we want to define the algebra as an intermediate language for the compilation of feature-logic database-queries, we augment it by a closure-operator to be able to compile recursive queries. Formal semantics of this Extended Feature-Term Algebra (EFTA) are given, its expressive power is investigated, and the algebra is discussed in the context of related work.</abstract><subject><genre>Keywords</genre><topic>Deductive database</topic><topic>Complex object algebra</topic><topic>Open world assumption</topic><topic>Recursive queries</topic></subject><relatedItem type="host"><titleInfo><title>Data & Knowledge Engineering</title></titleInfo><titleInfo type="abbreviated"><title>DATAK</title></titleInfo><genre type="journal">journal</genre><originInfo><dateIssued encoding="w3cdtf">199103</dateIssued></originInfo><identifier type="ISSN">0169-023X</identifier><identifier type="PII">S0169-023X(00)X0079-1</identifier><part><date>199103</date><detail type="volume"><number>6</number><caption>vol.</caption></detail><detail type="issue"><number>2</number><caption>no.</caption></detail><extent unit="issue pages"><start>101</start><end>178</end></extent><extent unit="pages"><start>125</start><end>149</end></extent></part></relatedItem><identifier type="istex">83D907268DC7AC753A5F773B98B4C1593D03C087</identifier><identifier type="DOI">10.1016/0169-023X(91)90019-T</identifier><identifier type="PII">0169-023X(91)90019-T</identifier><recordInfo><recordContentSource>ELSEVIER</recordContentSource></recordInfo></mods></metadata><serie></serie></istex></record>Pour manipuler ce document sous Unix (Dilib)
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