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Query Rewriting On Path Views Without Integrity Constraints [article]

Julien Romero, Nicoleta Preda, Fabian Suchanek
2020 arXiv   pre-print
To answer a query on such views, one has to orchestrate the views together in execution plans.  ...  However, such rewritings are usually possible only in the presence of integrity constraints - and not all databases have such constraints.  ...  Equivalent rewritings rely on integrity constraints, which may not be available. These constraints are difficult to mine, as most real-life rules have exceptions.  ... 
arXiv:2010.03527v1 fatcat:ntv2fcfdbrhajkhgfcebw6lqg4

Data integration

Maurizio Lenzerini
2002 Proceedings of the twenty-first ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '02  
For queries and views that are conjunctive queries (without union), the perfect rewriting is a union of conjunctive queries and hence is PTIME [1] .  ...  Table 1 : 1 Complexity of view-based query answering Table 2 : 2 Complexity of view-based query answering for regular-path queries in M be a data integration system, where G is constituted by the  ... 
doi:10.1145/543613.543644 dblp:conf/pods/Lenzerini02 fatcat:dt4h6ll3ojfaniqonbaelhdcxu

Query Processing in Data Integration

Paolo Guagliardo, Piotr Wieczorek, Marc Herbstritt
2013 Dagstuhl Publications  
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  ...  A rewriting Q r ∈ L r of a query Q ∈ L q under exact views V is L r -maximal iff, there exists no rewriting Q r ∈ L r of Q under V such that Q r V R (D) ⊃ Q r V R (D) for some database D.  ...  (which without integrity constraints reduces to query unfolding) difficult [10] .  ... 
doi:10.4230/dfu.vol5.10452.129 dblp:conf/dagstuhl/GuagliardoW13 fatcat:2bqbnhu3wbe3rcvsck6aqzr3em

Data integration

Maurizio Lenzerini
2002 Proceedings of the twenty-first ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '02  
For queries and views that are conjunctive queries (without union), the perfect rewriting is a union of conjunctive queries and hence is PTIME [1] .  ...  Table 1 : 1 Complexity of view-based query answering Table 2 : 2 Complexity of view-based query answering for regular-path queries in M be a data integration system, where G is constituted by the  ... 
doi:10.1145/543643.543644 fatcat:hz77ck7elzgxjbtdoqxuyeh73q

Peer-based Query Rewriting in SPARQL for Semantic Integration of Linked Data

Mirko Michele Dimartino
2015 International Semantic Web Conference  
We aim to achieve query answering by generating the perfect rewriting of the original query and then processing the rewritten query over distributed SPARQL endpoints.  ...  We identify a subset of ontology constraints that enjoy the first-order rewritability property and we perform preliminary empirical evaluation taking into account such restricted constraints only.  ...  Different from the existing SPARQL rewriting approaches, our integration framework preserves the expressive power of both the global-as-view and local-as-view integration formalisms.  ... 
dblp:conf/semweb/Dimartino15 fatcat:ksq4zjumqzbelj4zgb77trx2dq

Physical Data Independence, Constraints, and Optimization with Universal Plans

Alin Deutsch, Lucian Popa, Val Tannen
1999 Very Large Data Bases Conference  
We prove that it is in fact complete for \path-conjunctive" queries and views with complex objects, classes and dictionaries, going beyond previous theoretical work on processing queries using materialized  ...  The search space for query plans is dened and enumerated in a novel manner: the chase phase rewrites the original query into a \universal" plan that integrates all the access structures and alternative  ...  We can stop this rewriting anytime and it will still be sound (under the constraints) for a large class of queries, views, indexes and constraints.  ... 
dblp:conf/vldb/DeutschPT99 fatcat:3dmlapd6vvhdrd4tc7c6wg6dna

PAIRSE

Djamal Benslimane, Mahmoud Barhamgi, Frederic Cuppens, Franck Morvan, Bruno Defude, Ebrahim Nageba
2013 SIGMOD record  
needs on the fly.  ...  The proposed integration system was demonstrated at EDBT 2013 and VLDB 2011.  ...  This mapping path allows the translation of RPV views. We proposed a query rewriting based service composition algorithm to select and compose data services on the fly [7, 9] .  ... 
doi:10.1145/2536669.2536677 fatcat:besptcfi4rcnxoitl25b7frcz4

Page 3296 of Mathematical Reviews Vol. , Issue 2004d [page]

2004 Mathematical Reviews  
Summary: “Rewriting queries using views is a powerful technique that has applications in query optimization, data integration, data warehousing, etc.  ...  In this paper we focus on extracting as much information as possible from algebraic rewritings for the purpose of optimizing regular path queries.  ... 

Enabling ontology evolution in data integration

Haridimos Kondylakis, Dimitris Plexousakis
2010 Proceedings of the 1st International Workshop on Data Semantics - DataSem '10  
In this dissertation, we provide a solution that allows query answering under evolving ontologies without mapping redefinition. This is achieved by exploiting query rewriting.  ...  That module gets as input the different ontology versions and the user query, and rewrites the query over data integration systems that use different ontology versions.  ...  For queries and views that are conjunctive queries (without union), the perfect rewriting is a union of conjunctive queries and hence is PTIME.  ... 
doi:10.1145/1754239.1754282 dblp:conf/edbtw/KondylakisP10 fatcat:xed76gncrja73bszmo6mws5aym

Access patterns and integrity constraints revisited

Vince Bárány, Michael Benedikt, Pierre Bourhis
2013 Proceedings of the 16th International Conference on Database Theory - ICDT '13  
Unlike prior work, we focus on integrity constraint languages that subsume inclusion dependencies.  ...  We consider which queries are answerable in the presence of access restrictions and integrity constraints, and which portions of the schema are accessible in the presence of access restrictions and constraints  ...  This is a trivial notion without integrity constraints -the only way we can extract all the data from a position is if we have an input-free access on that relation.  ... 
doi:10.1145/2448496.2448522 dblp:conf/icdt/BaranyBB13 fatcat:aexm4ssya5fkbl5jteqnfwixtq

Dynamic Data Warehouse Design [chapter]

Dimitri Theodoratos, Timos Sellis
1999 Lecture Notes in Computer Science  
Based on an AND OR dag representation of multiple queries, we model the problem as a state space search problem.  ...  When a query is posed, it is evaluated locally, using the materialized views, without accessing the original information sources. The DWs are dynamic entities that evolve continuously over time.  ...  . 12 considers the problem for materialized views but without space constraints.  ... 
doi:10.1007/3-540-48298-9_1 fatcat:tf3fpujbgzhu5j7txmmcsq7dhm

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  
Losslessness holds if we can answer the query by solely relying on the content of the views.  ...  this setting, i.e., two-way regular path queries.  ...  The notions above can be extended to two-way path queries, which are defined similarly to 2RPQs, but without requiring the language to be regular.  ... 
doi:10.1007/978-3-540-30570-5_22 fatcat:tbv7mpggovakdfqgtqgmkizy5y

Query rewriting for semistructured data

Yannis Papakonstantinou, Vasilis Vassalos
1999 Proceedings of the 1999 ACM SIGMOD international conference on Management of data - SIGMOD '99  
We develop and present an algorithm that, given a semistructured query q and a set of semistructured views V, nds rewriting queries, i.e., queries that access the views and produce the same result as q  ...  W e extend the rewriting algorithm to use available structural constraints such as DTDs to nd more opportunities for query rewriting. We currently incorporate the algorithm in the TSIMMIS system.  ...  Acknowledgements We are grateful to Je Ullman and Victor Vianu for their comments and suggestions on an earlier draft of this paper.  ... 
doi:10.1145/304182.304222 dblp:conf/sigmod/PapakonstantinouV99 fatcat:s5moeofgnzct5kmoon5k4fkcta

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  
Losslessness holds if we can answer the query by solely relying on the content of the views.  ...  this setting, i.e., two-way regular path queries.  ...  The notions above can be extended to two-way path queries, which are defined similarly to 2RPQs, but without requiring the language to be regular.  ... 
doi:10.1016/j.tcs.2006.11.006 fatcat:w5uqnlfdsveipfrhbfcapvx5s4

Query rewriting for semistructured data

Yannis Papakonstantinou, Vasilis Vassalos
1999 SIGMOD record  
We develop and present an algorithm that, given a semistructured query q and a set of semistructured views V, nds rewriting queries, i.e., queries that access the views and produce the same result as q  ...  W e extend the rewriting algorithm to use available structural constraints such as DTDs to nd more opportunities for query rewriting. We currently incorporate the algorithm in the TSIMMIS system.  ...  Acknowledgements We are grateful to Je Ullman and Victor Vianu for their comments and suggestions on an earlier draft of this paper.  ... 
doi:10.1145/304181.304222 fatcat:gfvtf3nbgjcyvdhcaotkjv4qpi
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