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Ub-Tree Indexing For Semantic Query Optimization Of Range Queries

S. Housseno, A. Simonet, M. Simonet
2009 Zenodo  
Semantic query optimization consists in restricting the search space in order to reduce the set of objects of interest for a query.  ...  This approach has been developed in the context of a KB-DBMS but it can be applied to any relational system.  ...  This model has been implemented in the KB-DBMS prototype Osiris.  ... 
doi:10.5281/zenodo.1079716 fatcat:nnd37mb4orh35hpft76k66icsu

Optimizing Taxonomic Semantic Web Queries Using Labeling Schemes

V. Christophides, G. Karvounarakis, D. Plexousakis, Michel Scholl, Sotirios Tourtounis
2004 Social Science Research Network  
We advocate for the use of labeling schemes for modeling these hierarchies in order to efficiently answer queries such as subsumption check, descendants, ancestors or nearest common ancestor, which usually  ...  We then show that two labeling schemes are good candidates for an efficient implementation of label querying using standard relational DBMS, namely the Dewey Prefix scheme and an Interval scheme by Agrawal  ...  We focus on the optimization of a large class of queries, central to semantic web applications, namely the queries on class hierarchies.  ... 
doi:10.2139/ssrn.3199016 fatcat:c563djn7svbkxev5h2y6h7dusu

Optimizing taxonomic semantic web queries using labeling schemes

V. Christophides, G. Karvounarakis, D. Plexousakis, Michel Scholl, Sotirios Tourtounis
2004 Journal of Web Semantics  
We advocate for the use of labeling schemes for modeling these hierarchies in order to efficiently answer queries such as subsumption check, descendants, ancestors or nearest common ancestor, which usually  ...  We then show that two labeling schemes are good candidates for an efficient implementation of label querying using standard relational DBMS, namely the Dewey Prefix scheme and an Interval scheme by Agrawal  ...  We focus on the optimization of a large class of queries, central to semantic web applications, namely the queries on class hierarchies.  ... 
doi:10.1016/j.websem.2003.11.001 fatcat:ekkwvbdphrd7zpjknps6cqyt6u

OptImatch: Semantic web system for query problem determination

Guilherme Damasio, Piotr Mierzejewski, Jaroslaw Szlichta, Calisto Zuzarte
2016 2016 IEEE 32nd International Conference on Data Engineering (ICDE)  
We introduce a novel semantic web system that allows a relatively naive user to search for arbitrary patterns and to get solution recommendations stored in a knowledge base.  ...  Database query performance problem determination is often performed by analyzing query execution plans (QEPs) in addition to other performance data.  ...  This is one of the main strengths of SQL, as it means that it should not make a difference to the query optimizer how a query is written as long as the different versions are semantically equivalent.  ... 
doi:10.1109/icde.2016.7498338 dblp:conf/icde/DamasioMSZ16 fatcat:jqlnj56mmfetxjsjfssot6hhwe

OptImatch: Semantic Web System with Knowledge Base for Query Performance Problem Determination [article]

Guilherme Damasio, Piotr Mierzejewski, Jaroslaw Szlichta, Calisto Zuzarte
2015 arXiv   pre-print
We introduce a novel semantic web system that allows a relatively naive user to search for arbitrary patterns and to get recommendations stored in a knowledge base either by experts or added by the user  ...  Database query performance problem determination is often performed by analyzing query execution plans (QEPs) in addition to other performance data.  ...  This is one of the main strengths of SQL, as it means that it should not make a difference to the query optimizer how a query is written as long as the different versions are semantically equivalent.  ... 
arXiv:1510.03302v1 fatcat:azvdmvukhvc2ndnx4lpsbzw6nq

Inconsistency-tolerant query answering in ontology-based data access

Domenico Lembo, Maurizio Lenzerini, Riccardo Rosati, Marco Ruzzi, Domenico Fabio Savo
2015 Journal of Web Semantics  
Our general goal is both to study DL semantical frameworks that are inconsistency-tolerant, and to devise techniques for answering unions of conjunctive queries under such inconsistency-tolerant semantics  ...  In the rest of the paper, when it is clear from the context, we often implicitly refer to Γ.  ...  This research has been partially supported by the EU under FP7 project Optique -Scalable End-user Access to Big Data (grant n. FP7-318338).  ... 
doi:10.1016/j.websem.2015.04.002 fatcat:kcrhpvmymzaonmngkey5i43pkq

A general Datalog-based framework for tractable query answering over ontologies

Andrea Calì, Georg Gottlob, Thomas Lukasiewicz
2012 Journal of Web Semantics  
It paves the way for applying results from databases to the context of the Semantic Web.  ...  We also show how stratified negation can be added to Datalog ± while keeping ontology querying tractable.  ...  of the optimizations of an underlying relational DBMS.  ... 
doi:10.1016/j.websem.2012.03.001 fatcat:yvjyqtstn5a6dlht5qhnpzgyoy

Complexity of answering counting aggregate queries over DL-Lite

Egor V. Kostylev, Juan L. Reutter
2015 Journal of Web Semantics  
We propose an intuitive semantics for certain answers for these queries, which conforms to the open world assumption.  ...  We compare our semantics with other approaches that have been proposed in different contexts.  ...  Counting Queries over Ontologies The ability to evaluate aggregate queries is a default in every DBMS and is in the standard of SQL.  ... 
doi:10.1016/j.websem.2015.05.003 fatcat:i7edc4lmzrcvrenrmaptm2tqym

SPARQL query answering with bitmap indexes

Julien Leblay
2012 Proceedings of the 4th International Workshop on Semantic Web Information Management - SWIM '12  
In this setting, one can even query the data without resorting to backward chaining, using a so-called semantic index. However, these techniques are limited in the type of queries they can support.  ...  This is usually achieved through forward chaining, with space and maintenance overheads, or backward chaining, with high query evaluation and optimization costs.  ...  x rdf:type :Artist} The upcoming SPARQL 1.1 specification defines the notion of entailment regimes, whereby the DBMS may override the semantics of the triple pattern matching, typically to retrieve triples  ... 
doi:10.1145/2237867.2237876 dblp:conf/sigmod/Leblay12 fatcat:4land3jf2zalfnejh427oou7pm

Query Optimization in OODBMS: Identifying Subquery for Query Management

Sheetal S. Dhande, Bamnote G.R
2014 International Journal of Database Management Systems  
Multiple experiments were performed to prove the productivity of this newer way of optimizing a query.  ...  This paper is based on relatively newer approach for query optimization in object databases, which uses query decomposition and cached query results to improve execution a query.  ...  Query Normalization To prevent from placing in the cache, queries with different textual forms but the same semantic meaning (& hence also will generate the same result), several query text normalization  ... 
doi:10.5121/ijdms.2014.6204 fatcat:qn36ajpfqbfnzlmmsekzvnwgpy

Quantifying TPC-H choke points and their optimizations

Markus Dreseler, Martin Boissier, Tilmann Rabl, Matthias Uflacker
2020 Proceedings of the VLDB Endowment  
Three queries (Q2, Q17, and Q21) are strongly influenced by the choice of an efficient query plan; three others (Q1, Q13, and Q18) are less influenced by plan optimizations and more dependent on an efficient  ...  It poses a number of challenges, also known as "choke points", which database systems have to solve in order to achieve good benchmark results.  ...  Acknowledgements We thank the TU Munich database group for providing us with early access to Umbra.  ... 
doi:10.14778/3389133.3389138 fatcat:lfjnnobaw5b5tcj5a7o55ytcm4

Knowledge Model For Human Resource Optimization

EPFL
2016 Zenodo  
This deliverable describes the second and final version of the SatisFactory knowledge model for Human Resource optimization.  ...  Query In the framework of Semantic Web, the meaning of "query" is related to technologies and protocols that allows information retrieval.  ...  The knowledge-base (KB) developed to reason on semantic data, which are shared through the system according to predefined XSD schemas, has to be built according to an "opposite" approach (approach).  ... 
doi:10.5281/zenodo.1005098 fatcat:zbyv6hmrmbgxvj5f7wnoqz7ck4

Connectivity-Tolerant Query Optimization over Distributed Mobile Repositories

Sharma Chakravarthy, Aditya Telang, Mohan Kumar, Mark Linderman, Sanjay Madria, Waseem Naqvi
2012 International Conference on Management of Data  
Query processing and optimization in centralized and distributed environments is well-researched. Centralized query optimization focused on minimizing the number of input/output (or I/O) from disk.  ...  We propose and evaluate several heuristics for this environment ranging from greedy to cumulative approaches along with the use of replicated copies of data.  ...  Other forms of query optimization, such as semantic query optimization [9] , multiple query optimization [8, 20] , and more recently, continuous query processing [6] have focused on modeling, scheduling  ... 
dblp:conf/comad/ChakravarthyTKLMN12 fatcat:duc73merijdevgred5pudj4iy4

A Dynamic, Cost-Aware, Optimized Maintenance Policy for Interactive Exploration of Linked Data

Usman Akhtar, Anita Sant' Anna, Sungyoung Lee
2019 Applied Sciences  
However, accessing Linked Data at query time is prohibitive due to high latency in searching the content and the limited capacity of current tools to connect to these databases.  ...  Many of the current analytics solutions require continuous access to these data sets.  ...  Semantic caching was originally proposed for Database Management System (DBMS) [27] to reduce the overhead when retrieving data over a network.  ... 
doi:10.3390/app9224818 fatcat:xz7ahzxg3vef7hrtidd7nnyt5u

Knowledge Model For Human Resource Optimization

EPFL
2016 Zenodo  
This deliverable describes the second and final version of the SatisFactory knowledge model for Human Resource optimization.  ...  Query In the framework of Semantic Web, the meaning of "query" is related to technologies and protocols that allows information retrieval.  ...  Therefore, the need to define data from a conceptual view has led to the development of semantic data modeling techniques.  ... 
doi:10.5281/zenodo.1005095 fatcat:iayos7arjjfqhnfi2b22nnuz5u
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