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Shape-Based Visual Query Rewriting

Georges Chalhoub, Richard Chbeir, Kokou Yetongnon
2006 2006 IEEE International Conference on Multimedia and Expo  
In this paper, we present a new cooperative approach based on the shape neighbourhood concept allowing the user to rewrite a shape-based visual query according to his preferences with high flexibility  ...  A visual query is based on pictorial representation of conceptual entities and operations. One of the most important features used in visual queries is the shape.  ...  Shape Based Query Rewritng In this paper, we extend the textual-oriented rewriting approach presented in [22] by considering the shape feature and providing a flexible formal language for shape-based  ... 
doi:10.1109/icme.2006.262518 dblp:conf/icmcs/ChalhoubCY06 fatcat:meomra7dmrbz5ef3ripju7sfjq

JPA Criteria Queries over RDF Data

Claus Stadler, Jens Lehmann
2017 Extended Semantic Web Conference  
Our contributions comprise (i) a system design for enabling JPA compliant object/RDF mappings together with de-/serialization of object graphs as RDF, (ii) an approach for rewriting criteria queries to  ...  We present the design and implementation of a prototype system for querying RDF data via the Java Persistence API (JPA) criteria query feature.  ...  (ii) Unified querying over RDBs and triple stores via the criteria API, as well as higher flexibility in exchanging backends.  ... 
dblp:conf/esws/StadlerL17 fatcat:omz3qedisng7fee5lry42cnzua

Query Answering in Description Logics: The Knots Approach [chapter]

Thomas Eiter, Carsten Lutz, Magdalena Ortiz, Mantas Šimkus
2009 Lecture Notes in Computer Science  
When annotated with suitable query information, knots are a flexible tool for query answering that allows for solving the problem in a simple and intuitive way.  ...  In the recent years, query answering over Description Logic (DL) knowledge bases has been receiving increasing attention, and various methods and techniques have been presented for this problem.  ...  The first step is presented in the current section, where we give a knot-based algorithm for query entailment in ALCHI that presupposes tree-shaped queries and runs in ExpTime.  ... 
doi:10.1007/978-3-642-02261-6_3 fatcat:6dmw3kd4mnfi5anf3idv2gjcj4

Geographic intention and modification in web search

Rosie Jones, Wei V. Zhang, Benjamin Rey, Pradhuman Jhala, Eugene Stipp
2008 International Journal of Geographical Information Science  
We also examine query rewriting: both deliberate query rewriting, conducted in web search sessions, and automated query rewriting, with manual relevance judgements of geo-modified queries.  ...  We also give distance profiles for the top topics which cooccur with place-names in queries, which could be used to set document priors based on document proximity and query topic.  ...  For example, the query "castles near edinburgh" has three phrases we could modify, and based on user query rewrite session distribution, candidate rewrites for each phrase include "castles" → "medieval  ... 
doi:10.1080/13658810701626186 fatcat:dyhqq66tjngyplttxwwquyxari

Versatile optimization of UDF-heavy data flows with sofa

Astrid Rheinländer, Martin Beckmann, Anja Kunkel, Arvid Heise, Thomas Stoltmann, Ulf Leser
2014 Proceedings of the 2014 ACM SIGMOD international conference on Management of data - SIGMOD '14  
Such queries are optimized by Sofa, building on a concise set of UDF annotations and a small set of rewrite rules to enable semantically equivalent plan rewriting of UDF-heavy data flows.  ...  In this demonstration, we will let users pose arbitrary Meteor queries and graphically showcase versatility and extensibility of Sofa during query optimization.  ...  for the audience to interact with the system, i.e., by writing own queries, by interfering with the optimization process, and by learning about the integration of novel operators into the Meteor query  ... 
doi:10.1145/2588555.2594517 dblp:conf/sigmod/RheinlanderBKHSL14 fatcat:i577qqaydjgy7bvihk4ftjpecu

RDF/RDFS-based Relational Database Integration

Huajun Chen, Zhaohui Wu, Heng Wang, Yuxin Mao
2006 22nd International Conference on Data Engineering (ICDE'06)  
We formally define the query semantics in such an integration scenario, and design a novel query rewriting algorithm to implement the semantics.  ...  We study the problem of answering queries through a RDF/RDFS ontology, given a set of view-based mappings between one or more relational schemas and this target ontology.  ...  In these two case, we consider queries and views that have the same shape and size.  ... 
doi:10.1109/icde.2006.127 dblp:conf/icde/ChenWWM06 fatcat:f6ah6udy5zahhem42cwz2vmxde

The MemSQL query optimizer

Jack Chen, Samir Jindel, Robert Walzer, Rajkumar Sen, Nika Jimsheleishvilli, Michael Andrews
2016 Proceedings of the VLDB Endowment  
We discuss methods to make join enumeration faster and more effective, such as a rewrite-based approach to exploit bushy joins in queries involving multiple star schemas without sacrificing optimization  ...  needs to be distribution-aware in choosing join plans, applying query rewrites, and costing plans.  ...  We look for common query shapes that benefit from bushy plans and introduce bushiness via the framework of a query rewrite.  ... 
doi:10.14778/3007263.3007277 fatcat:gbbm7sr6e5gnfiq2q4jrhimqs4

SOFA: An Extensible Logical Optimizer for UDF-heavy Dataflows [article]

Astrid Rheinländer, Arvid Heise, Fabian Hueske, Ulf Leser, Felix Naumann
2013 arXiv   pre-print
equivalent plan rewrites than possible with traditional techniques.  ...  It builds on a concise set of properties for describing the semantics of Map/Reduce-style UDFs and a small set of rewrite rules, which use these properties to find a much larger number of semantically  ...  We thank Martin Beckmann and Anja Kunkel for help with implementing the Meteor queries we used for evaluation, and we thank Volker Markl and Stephan Ewen for valuable discussion and feedback.  ... 
arXiv:1311.6335v1 fatcat:3sojpzy65vbgnetjygme655hwa

One Query to Bind Them All

Daniel M. Herzig, Thanh Tran
2011 International Semantic Web Conference  
Given the scale as well as the dynamics of Web datasets, even automatic rewriting is often infeasible.  ...  Thus, queries formulated for one dataset can not easily be reused for querying other datasets.  ...  Basically, there are two existing lines of approaches, one that is based on keyword search and the other one is structured query rewriting.  ... 
dblp:conf/semweb/HerzigT11 fatcat:e4hiwz442jfvhaos2svvsuoniu

Schema Validation and Evolution for Graph Databases [article]

Angela Bonifati, Peter Furniss, Alastair Green, Russ Harmer, Eugenia Oshurko, Hannes Voigt
2019 arXiv   pre-print
Our prototypical implementation demonstrates feasibility and shows the need of offering high-level query primitives to accommodate flexible graph schema requirements as showcased in our work.  ...  inspired by Cypher syntax, we show how schema validation can be enforced through homomorphisms between PG schemas and PG instances; and how schema evolution can be described through the use of graph rewriting  ...  These conditions are provided as shapes under the form of an RDF graph.  ... 
arXiv:1902.06427v1 fatcat:fwfhhbjrxvf6jgbl7corhimgwe

Query Answering over Description Logic Ontologies [chapter]

Diego Calvanese
2014 Lecture Notes in Computer Science  
The associated results, accompanied by matching lower bounds, have contributed to shaping the computational complexity picture for ontology-based query answering.  ...  We overview here some of the key techniques developed in the last years for query answering over DL ontologies, ranging from rewriting based approaches for lightweight DLs, to tableaux algorithms, and  ...  Query Answering by Rewriting in Lightweight DLs We illustrate now the approach to query answering based on query rewriting, which was first introduced for answering UCQs over DL-Lite ontologies through  ... 
doi:10.1007/978-3-319-11558-0_1 fatcat:pftzblg5nbdqzbyif5yw6aimma

A Neural-symbolic Approach for Ontology-mediated Query Answering [article]

Medina Andresel, Csaba Domokos, Daria Stepanova, Trung-Kien Tran
2021 arXiv   pre-print
More specifically, we propose various data augmentation strategies to generate training queries using query-rewriting based methods and then exploit a novel loss function for training the model.  ...  Recently, low-dimensional vector space representations of knowledge graphs (KGs) have been applied to find answers to conjunctive queries (CQs) over incomplete KGs.  ...  Query-rewriting based sampling.  ... 
arXiv:2106.14052v1 fatcat:a5nrik4pnjcnvkwysafysodbmu

SemLAV: Local-As-View Mediation for SPARQL Queries [chapter]

Gabriela Montoya, Luis-Daniel Ibáñez, Hala Skaf-Molli, Pascal Molli, Maria-Esther Vidal
2014 Lecture Notes in Computer Science  
Query processing requires to generate and execute query rewritings, but for SPARQL queries, the LAV query rewritings may not be generated or executed in a reasonable time.  ...  The paper presents an experimental study for SemLAV, and compares its performance with traditional LAV-based query processing techniques.  ...  Despite of its expressiveness and flexibility, LAV suffers from well-known drawbacks: (i) existing LAV query rewriters only manage conjunctive queries, (ii) the query rewriting problem is NP-complete for  ... 
doi:10.1007/978-3-642-54426-2_2 fatcat:ujikj3tntbhgvjcmrwwf2csmt4

SemLAV: Local-As-View Mediation for SPARQL Queries [chapter]

Gabriela Montoya, Luis-Daniel Ibáñez, Hala Skaf-Molli, Pascal Molli, Maria-Esther Vidal
2014 Lecture Notes in Computer Science  
Query processing requires to generate and execute query rewritings, but for SPARQL queries, the LAV query rewritings may not be generated or executed in a reasonable time.  ...  The paper presents an experimental study for SemLAV, and compares its performance with traditional LAV-based query processing techniques.  ...  Despite of its expressiveness and flexibility, LAV suffers from well-known drawbacks: (i) existing LAV query rewriters only manage conjunctive queries, (ii) the query rewriting problem is NP-complete for  ... 
doi:10.1007/978-3-662-45942-3_2 fatcat:zgyz362j5vg7ljwu33g7tbibyi

Relaxing XML Preference Queries for Cooperative Retrieval [chapter]

SungRan Cho, Wolf-Tilo Balke
2009 Lecture Notes in Business Information Processing  
In this paper we present a novel framework for developing preference relaxations to the query permitting additional flexibility in order to fulfil a user's wishes.  ...  query processing that allow preference querying and returning ranked answers.  ...  Then the query rewriter rewrites the query into conventional XPath or XQuery queries which can be executed in any conventional XML engine, by expanding the query with the user provided preferences.  ... 
doi:10.1007/978-3-642-01347-8_14 fatcat:zmp6y2dz2bb27bdeabfgbyupiq
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