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View-based query processing for regular path queries with inverse

Diego Calvanese, Moshe Y. Vardi, Giuseppe de Giacomo, Maurizio Lenzerini
2000 Proceedings of the nineteenth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '00  
In this paper we address the problem of view-based query processing in the context of semistructured data, in particular for the case of regular-path queries extended with the inverse operator.  ...  computational complexity as for the case of standard regular-path queries.  ...  The existing approaches to view-based query processing for regular-path queries do not easily extend to the case with the inverse operator.  ... 
doi:10.1145/335168.335207 dblp:conf/pods/CalvaneseGLV00 fatcat:ihd2ag6v2vh6te7xdl73nx6ysq

Querying semi-structured data [chapter]

Serge Abiteboul
1997 Lecture Notes in Computer Science  
The two main approaches, query rewriting and view materialization, are outlined with focus on the di cult problems caused by the semistructured nature of the data.  ...  De ning a view over a semistructured database introduces many new problems. In this paper we propose a view speci cation language and consider the problem of answering queries posed over views.  ...  Acknowledgments We wish to thank Janet Wiener for many fruitful discussions during the early stages of this work and Je Ullman for helpful suggestions and comments.  ... 
doi:10.1007/3-540-62222-5_33 fatcat:v5kzroewpjff3o6iqyp7zkiluq

Reasoning on regular path queries

D. Calvanese, G. De Giacomo, M. Lenzerini, M. Y. Vardi
2003 SIGMOD record  
The goal of this paper is to describe basic results and techniques concerning query containment and view based query processing for the class of two-way regular-path queries (which extend RPQs with the  ...  Another important reasoning service that has received considerable attention in the recent years is view-based query processing, which amounts to processing queries based on a set of materialized views  ...  The goal of this paper is to describe basic results and techniques concerning query containment and view based query processing for the class of two-way regular-path queries.  ... 
doi:10.1145/959060.959076 fatcat:mzahrhzko5ap5kcuzfovoyg3di

A call to regularity

Moshe Y. Vardi
2003 Proceedings of the Paris C. Kanellakis memorial workshop on Principles of computing & knowledge Paris C. Kanellakis memorial workshop on the occasion of his 50th birthday - PCK50  
View-based query rewriting: approximate global query by a local query based on view definitions 3. View-based query losslessness: Compare global query with its view-based approximation. 4.  ...  · · l k ∈ L 1 Corollary: Path-Query Containment is • undecidable for context-free path queries • decidable for regular path queries.  ... 
doi:10.1145/778348.778352 fatcat:36cih6nywvaqdm5wkhgap23i3m

View-Based Query Processing: On the Relationship Between Rewriting, Answering and Losslessness [chapter]

Diego Calvanese, Giuseppe De Giacomo, Maurizio Lenzerini, Moshe Y. Vardi
2004 Lecture Notes in Computer Science  
this setting, i.e., two-way regular path queries.  ...  As a result of the extensive research in view-based query processing, three notions have been identified as fundamental, namely rewriting, answering, and losslessness.  ...  Introduction View-based query processing is the problem of computing the answer to a query based on a set of views [1] [2] [3] .  ... 
doi:10.1007/978-3-540-30570-5_22 fatcat:tbv7mpggovakdfqgtqgmkizy5y

View-based query processing: On the relationship between rewriting, answering and losslessness

Diego Calvanese, Giuseppe De Giacomo, Maurizio Lenzerini, Moshe Y. Vardi
2007 Theoretical Computer Science  
this setting, i.e., two-way regular path queries.  ...  As a result of the extensive research in view-based query processing, three notions have been identified as fundamental, namely rewriting, answering, and losslessness.  ...  Introduction View-based query processing is the problem of computing the answer to a query based on a set of views [1] [2] [3] .  ... 
doi:10.1016/j.tcs.2006.11.006 fatcat:w5uqnlfdsveipfrhbfcapvx5s4

View-Based Query Answering and Query Containment over Semistructured Data [chapter]

Diego Calvanese, Giuseppe De Giacomo, Maurizio Lenzerini, Moshe Y. Vardi
2002 Lecture Notes in Computer Science  
We consider conjunctive two-way regular path queries (C2RPQ's), which extend regular path queries with two features.  ...  Second, they allow for using conjunctions of atoms, where each atom specifies that a regular path query with inverse holds between two terms, where each term is either a variable or a constant.  ...  Recently view-based query processing has been studied for the case of RPQs.  ... 
doi:10.1007/3-540-46093-4_3 fatcat:wlyu7g7ayba2tbbg36qhkce7w4

View-based query containment

Diego Calvanese, Giuseppe De Giacomo, Maurizio Lenzerini, Moshe Y. Vardi
2003 Proceedings of the twenty-second ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '03  
In particular, for the two settings of conjunctive queries and two-way regular path queries, we provide both techniques and complexity bounds for the different variants of the problem.  ...  Finally, we study the relationship between view-based query containment and view-based query rewriting.  ...  We call this kind of processing view-based query processing [12] .  ... 
doi:10.1145/773153.773160 dblp:conf/pods/CalvaneseGLV03 fatcat:awxnuf4p6jbkfdxmmsmv4ddewu

Query Processing in Data Integration

Paolo Guagliardo, Piotr Wieczorek, Marc Herbstritt
2013 Dagstuhl Publications  
In this chapter we illustrate the main techniques for processing queries in data integration.  ...  The first part of the chapter focuses on the problem of query answering in the relational setting, and describes approaches based on variants of the chase, along with how to deal with integrity constraints  ...  In [20] , the same complexity results reported in [17] for RPQs are indeed shown to hold also in the case of regular path queries with inverse.  ... 
doi:10.4230/dfu.vol5.10452.129 dblp:conf/dagstuhl/GuagliardoW13 fatcat:2bqbnhu3wbe3rcvsck6aqzr3em

Generating Rewrite Rules by Browsing RDF Data

Ora Lassila
2006 2006 Second International Conference on Rules and Rule Markup Languages for the Semantic Web (RuleML'06)  
This system can substitute atomic query expressions with complex queries, effectively rewriting queries. We demonstrate that this approach can be used for simple reasoning in the context of RDF(S).  ...  In this paper we show how path queries in the WILBUR query engine can be augmented via the use of a simple rule system.  ...  There is a strong emphasis on machine-based interpretation of data and automatic (even autonomous) processing.  ... 
doi:10.1109/ruleml.2006.13 dblp:conf/ruleml/Lassila06 fatcat:ofc7nqubpve3xhgj3rs425w6oq

PrefixSolve

Sidan Gao, Kemafor Anyanwu
2013 Proceedings of the 22nd international conference on World Wide Web - WWW '13  
The generalization enables holistic evaluation of MSMD path queries without the need for query decomposition.  ...  In this paper, we propose an optimization technique for general MSMD path queries that generalizes an efficient algebraic approach for solving a variety of single-source path problems.  ...  support for different kinds of path queries to be possible, (ii) it has two distinct phases that can be split into a preprocessing phase and a query processing phase with the cost of the former dominating  ... 
doi:10.1145/2488388.2488426 dblp:conf/www/GaoA13 fatcat:2fhshkfgmjcavpz35yxf7sotx4

Expressing structural hypertext queries in graphlog

M. P. Consens, A. O. Mendelzon
1989 Proceedings of the second annual ACM conference on Hypertext - HYPERTEXT '89  
GraphLog is a visual query language in which queries are formulated by drawing graph patterns. The hyperdocument graph is searched for all occurrences of these patterns.  ...  ACKNOWLEDGMENTS The authors are grateful to Fred Lochovsky for his helpful comments and to Christine Knight and Frank Eigler for their contributions to the prototype.  ...  This can be combined with value-based queries on node attributes for a completely general query language.  ... 
doi:10.1145/74224.74247 dblp:conf/ht/ConsensM89 fatcat:kyb3n277vjh55abe3abhjvhsge

A language for provenance access control

Tyrone Cadenhead, Vaibhav Khadilkar, Murat Kantarcioglu, Bhavani Thuraisingham
2011 Proceedings of the first ACM conference on Data and application security and privacy - CODASPY '11  
This language also provides access to data based on integrity criteria. We have also built a prototype to show that this language can be implemented effectively using Semantic Web technologies.  ...  We support the idea of grouping by defining dynamic paths that are evaluated at query time based on incorporating regular expressions in our policies.  ...  Path Queries SPARQL is a RDF query language that is based around graph pattern matching [19] .  ... 
doi:10.1145/1943513.1943532 dblp:conf/codaspy/CadenheadKKT11 fatcat:ahl2dokrcbg5tovukxomtjkyj4

Replacement strategies for XQuery caching systems

Li Chen, Song Wang, Elke A. Rundensteiner
2004 Data & Knowledge Engineering  
To improve the query performance over XML documents in a distributed environment, we develop a semantic caching system named ACE-XQ for XQuery queries.  ...  As a result, less frequently used XML view fragments are replaced to maintain a better utilization of the cache space.  ...  In general, the complexity of containment is NPcomplete for the relational conjunctive query and even goes up to ExpSpace for conjunctive regular path queries even with inverse operators [3] .  ... 
doi:10.1016/j.datak.2003.10.002 fatcat:dxkjki2xdrgnrfej62ofhzgdgm

View Synthesis from Schema Mappings [article]

Diego Calvanese, Giuseppe De Giacomo, Maurizio Lenzerini, Moshe Y. Vardi
2010 arXiv   pre-print
are (two-way) regular path queries, as well as unions of conjunctions thereof.  ...  In this paper we deal with the issue of automating such a design process.  ...  Finally, by exploiting a language-theoretic characterization for containment of regular path queries with inverse (called two-way regular path queries) provided in [10] , we extend the congruence class-based  ... 
arXiv:1003.1179v1 fatcat:btcefwv4hbewfah2sgsq54qhq4
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