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Navigational XPath

Balder ten Cate, Maarten Marx
2007 SIGMOD record  
We survey expressivity results for navigational fragments of XPath 1.0 and 2.0, as well as Regular XPath ≈ . We also investigate algebras for these fragments.  ...  with transitive closure and path equalities.  ...  Regular XPath ≈ For Regular XPath ≈ , the algebras need to be extended with a transitive closure operator.  ... 
doi:10.1145/1328854.1328858 fatcat:kjouhgo2pnhftj26aj5vzovxhe

XPath, transitive closure logic, and nested tree walking automata

Balder ten Cate, Luc Segoufin
2008 Proceedings of the twenty-seventh ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '08  
the transitive closure of path expressions, and a subtree relativisation operator, allowing one to restrict attention to a specific subtree while evaluating a subexpression.  ...  We also present a temporal logic on trees that is expressively complete for FO(MTC), in the form of an extension of the XML document navigation language XPath with two operators: the Kleene star for taking  ...  Transitive closure logic FO(MTC) is the language of first-order logic extended with a monadic (reflexive) transitive closure operator.  ... 
doi:10.1145/1376916.1376952 dblp:conf/pods/CateS08 fatcat:wymzhsa76zc5bpkuyta2leno2e

XPath queries on streaming data

Feng Peng, Sudarshan S. Chawathe
2003 Proceedings of the 2003 ACM SIGMOD international conference on on Management of data - SIGMOD '03  
We present the design and implementation of the XSQ system for querying streaming XML data using XPath 1.0.  ...  Using a clean design based on a hierarchical arrangement of pushdown transducers augmented with buffers, XSQ supports features such as multiple predicates, closures, and aggregation.  ...  Then the transition arc for begin event that come out from the START state and reach a lower layer BPDT are marked with =. These arcs are called closure transitions.  ... 
doi:10.1145/872757.872810 dblp:conf/sigmod/PengC03 fatcat:xuhbbeim6fbfhkzvfft2w6cuua

XPath queries on streaming data

Feng Peng, Sudarshan S. Chawathe
2003 Proceedings of the 2003 ACM SIGMOD international conference on on Management of data - SIGMOD '03  
We present the design and implementation of the XSQ system for querying streaming XML data using XPath 1.0.  ...  Using a clean design based on a hierarchical arrangement of pushdown transducers augmented with buffers, XSQ supports features such as multiple predicates, closures, and aggregation.  ...  Then the transition arc for begin event that come out from the START state and reach a lower layer BPDT are marked with =. These arcs are called closure transitions.  ... 
doi:10.1145/872808.872810 fatcat:jfl3n2govfe6jpzzqmtcp2uy64

Logical Foundations of XML and XQuery [chapter]

Maarten Marx
2009 Lecture Notes in Computer Science  
XML is the underlying representation formalism of much web-data.  ...  Thanks are due to my coauthors of the presented material: Loredana Afanasiev, Balder ten Cate and Tim Gielissen [3, 4, 25, 64].  ...  For Regular XPath ≈ , the algebras need to be extended with a transitive closure operator.  ... 
doi:10.1007/978-3-642-03754-2_3 fatcat:qkmz7pgvmfc2hizddq3awke7hu

First Order Paths in Ordered Trees [chapter]

Maarten Marx
2004 Lecture Notes in Computer Science  
A conditional path is an axis relation of the form (one step axis::n[F]) + , denoting the transitive closure of the relation expressed by one step axis::n[F].  ...  As neither is expressible in navigational XPath we also give characterizations in terms of first order logic of the answer sets and the sets of paths navigational XPath can define.  ...  The semantics is as with standard Core XPath [5] , with (·) + interpreted as the transitive closure.  ... 
doi:10.1007/978-3-540-30570-5_8 fatcat:wp5zeiogbngz7glfm7zswjnrhe

XPath with Conditional Axis Relations [chapter]

Maarten Marx
2004 Lecture Notes in Computer Science  
We study the effect of adding conditional axis relations to XPath on its expressive power and the complexity of the query evaluation and query equivalence problems.  ...  With it we can express paths specified by for instance "do a child step, while test is true at the resulting node".  ...  Theorem 4 below states that every first order expressible set of nodes can be described as an XPath expression with transitive closure over conditional paths.  ... 
doi:10.1007/978-3-540-24741-8_28 fatcat:xdemxjaibfehdlga72ia6y66iu

Querying Linguistic Trees

Catherine Lai, Steven Bird
2009 Journal of Logic, Language and Information  
We describe the domain of linguistic trees and discuss the expressive requirements for a query language.  ...  Existing languages suffer from a variety of problems in the areas of expressiveness, efficiency, and naturalness for linguistic query.  ...  Core XPath LPath LPath + ≡ Conditional XPath (27) Along with the proof of the X c * closure under complementation, Marx (2005) provides a method for finding the complement of any X c * path set.  ... 
doi:10.1007/s10849-009-9086-9 fatcat:elhvlorrmbdjdnclendesqvpmm

Designing and Evaluating an XPath Dialect for Linguistic Queries

S. Bird, Yi Chen, S.B. Davidson, Haejoong Lee, Yifeng Zheng
2006 22nd International Conference on Data Engineering (ICDE'06)  
In this paper, we motivate and illustrate these features with a variety of linguistic queries.  ...  In this paper, we motivate and illustrate these features with a variety of linguistic queries.  ...  and transitive closures for vertical and horizontal navigation, filling a gap in the XPath axis set.  ... 
doi:10.1109/icde.2006.48 dblp:conf/icde/BirdCDLZ06 fatcat:sob2vp27d5grzllranl2qlaqae

XSQ

Feng Peng, Sudarshan S. Chawathe
2005 ACM Transactions on Database Systems  
We present a detailed experimental study that characterizes the performance of XSQ and related systems, and that illustrates the performance implications of XPath features such as closures.  ...  We have implemented and released the XSQ system for evaluating XPath queries on streaming XML data.  ...  Diaz and Douglas Lovell the XML Generator; Oliver Becker for the Joost program and assistance with the code; the Graphviz team (John Ellson, Emden Gansner, Eleftherios Koutsofios, John Mocenigo, Stephen  ... 
doi:10.1145/1071610.1071617 fatcat:xurcoezgsnc7xgm6twe7dn7pey

Querying graph databases with XPath

Leonid Libkin, Wim Martens, Domagoj Vrgoč
2013 Proceedings of the 16th International Conference on Database Theory - ICDT '13  
This further confirms the usefulness of XPath for graph querying. Full GXPath reg is more expressive and corresponds to a fragment of the transitive closure logic.  ...  Therefore, XPath-like languages seem to be very well-suited to query graphs. Summary of the results. We start by studying the expressive power.  ...  The authors would like to thank Juan Reutter for helpful comments during the preparation of this manuscript.  ... 
doi:10.1145/2448496.2448513 dblp:conf/icdt/LibkinMV13 fatcat:i34u6ty3afh3na3yay6s3ab76a

Conditional XPath, the first order complete XPath dialect

Maarten Marx
2004 Proceedings of the twenty-third ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '04  
What is missing at present is a clear characterization of the expressive power of XPath, be it either semantical or with reference to some well established existing (logical) formalism.  ...  Core XPath (the logical core of XPath 1.0 defined by Gottlob et al.) cannot express queries with conditional paths as exemplified by "do a child step, while test is true at the resulting node."  ...  For the vertical direction, both transitive and reflexive-transitive closure of the basic steps are primitives.  ... 
doi:10.1145/1055558.1055562 dblp:conf/pods/Marx04 fatcat:2mlg33wnwndirlxugb2ueqyg44

Modal Logic Foundations of Markup Structures in Annotation Systems [chapter]

Marcus Kracht
2011 Studies in Computational Intelligence  
It will be seen that there is a tight connection between XPath and dynamic logic over ordered trees. This connection allows to get a good insight into the semantics and complexity of XPath.  ...  The reflexive and transitive closure of K, denoted by K * , is the transitive closure of K ∪ { w, w : w ∈ W}. Also, K := { y, x : x, y ∈ K} is called the converse of K.  ...  In XPath terminology, we change the focus (see [10] ). 3. R(← * ) is the reflexive and transitive closure of R(←). R(←) is the converse of R(→).  ... 
doi:10.1007/978-3-642-22613-7_7 fatcat:gzd72mn4kfa75o6x472k73iagy

High-performance complex event processing over XML streams

Barzan Mozafari, Kai Zeng, Carlo Zaniolo
2012 Proceedings of the 2012 international conference on Management of Data - SIGMOD '12  
In fact, the following was declared to be an important open problem since 2006 [31]: Efficient algorithms for computing the transitive closure of XPath path expressions.  ...  Specifically, the XSeq language extends XPath with natural operators to express sequential and Kleene-* patterns over XML streams, while remaining highly amenable to efficient implementation.  ...  In analogy to YFilter [10] , where thousands of XPath expressions were merged into one NFA, the fact that VPAs are closed under union creates important opportunities for concurrent execution of numerous  ... 
doi:10.1145/2213836.2213866 dblp:conf/sigmod/MozafariZZ12 fatcat:jxfthfm3srdrtkczao7cdsbxia

XPath for DL Ontologies

Egor Kostylev, Juan Reutter, Domagoj Vrgoc
2015 PROCEEDINGS OF THE THIRTIETH AAAI CONFERENCE ON ARTIFICIAL INTELLIGENCE AND THE TWENTY-EIGHTH INNOVATIVE APPLICATIONS OF ARTIFICIAL INTELLIGENCE CONFERENCE  
We start with adapting the definition of XPath to the DL context, and then proceed to study the complexity of evaluating XPath queries over knowledge bases.  ...  Results show that, while query answering is undecidable for the full XPath, by carefully tuning the shape of negation allowed in the queries we can arrive at XPath fragments that have a potential to be  ...  Reutter and Vrgoč are supported by the Millennium Nucleus Center for Semantic Web Research Grant NC120004.  ... 
doi:10.1609/aaai.v29i1.9396 fatcat:g3o4ivwjefg2zcrh7cu7kxpv7q
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