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Special issue on best papers of VLDB 2015

Chen Li, Volker Markl
2016 The VLDB journal  
of conjunctive queries.  ...  The authors propose a method for probabilistic inference, where a query is evaluated entirely in the database engine by evaluating a fixed number of query plans, each providing an upper bound on the true  ...  The authors also introduce a simple method to estimate the selectivity of inequality joins in order to optimize conjunctive queries and multi-way joins.  ... 
doi:10.1007/s00778-016-0450-5 fatcat:bs244b7w6fbflnahsx5cctaqfi

Queries over Web Services [chapter]

Efthymia Tsamoura, Anastasios Gounaris, Yannis Manolopoulos
2011 Studies in Computational Intelligence  
The characteristics of these two state-of -the-art algorithms for the optimization of queries over WSs in a pipelined parallel environment are summarized in Table 4 .  ...  ,Q M } be a set of M, potentially continuous select queries that are evaluated over a set of N selective, unconstrained and correlated operators O. Each query is a conjunction of the operators in O.  ... 
doi:10.1007/978-3-642-17551-0_6 fatcat:3xjcwgl57jbbtgosgzayihq7yq

Scaling Out Sound and Complete Reasoning for Conjunctive Queries on OWL Knowledge Bases

Sambhawa Priya
2015 International Semantic Web Conference  
and queryexecution tasks involved in processing conjunctive queries to nodes of the cluster.  ...  The focus of this thesis is to develop a scalable framework to perform sound and complete reasoning on large and expressive data graphs for answering conjunctive queries over a cluster of commodity machines  ...  Michael Spear (co-adviser) for their valuable comments on this paper.  ... 
dblp:conf/semweb/Priya15 fatcat:4shbvnicfrhizbd4jijqb3dpa4

Let's Rethink Join Optimization in Distributed Systems

Semih Salihoglu
2015 Conference on Innovative Data Systems Research  
One of the core operations performed by these  ...  The advent of Google's MapReduce [2] and Hadoop [3] has been followed by a series of systems with relational operators or SQL-like interfaces, such as Pig [8], Hive [10], Spark [12], SparkSQL [9], and  ...  The specific problem we consider is the evaluation a conjunctive join query Q of m relations R1, ..., Rm on a cluster of p distributed machines.  ... 
dblp:conf/cidr/Salihoglu15 fatcat:nfms3aaih5dajhoirdioozvvzi

Query processing strategies in the PASCAL/R relational database management system

Matthias Jarke, Joachim W. Schmidt
1982 Proceedings of the 1982 ACM SIGMOD international conference on Management of data - SIGMOD '82  
The paper concentrated on logic-based transformations, Ongoing research tries to integrate them with optimal use of permanent access paths and to develop further appmaches to improve the phase structure  ...  We would also like to thank Juergen Koch, Ted Stohr, and one of the referees for helpful comments which improved the English presentation of the paper.  ...  strong impact on the time and storage consumption of query evaluation.  ... 
doi:10.1145/582353.582402 dblp:conf/sigmod/JarkeS82 fatcat:w5jrqga555go3jqjcmdc3irghe

CliqueSquare: Flat plans for massively parallel RDF queries

Francois Goasdoue, Zoi Kaoudi, Ioana Manolescu, Jorge-Arnulfo Quiane-Ruiz, Stamatis Zampetakis
2015 2015 IEEE 31st International Conference on Data Engineering  
We present CliqueSquare, a novel optimization approach for evaluating conjunctive RDF queries in a massively parallel environment.  ...  on each node in order to compute the query answers.  ...  In this work, we focus on the logical optimization of BGP queries for massively parallel environments.  ... 
doi:10.1109/icde.2015.7113332 dblp:conf/icde/GoasdoueKMQZ15 fatcat:vvikryub6ja4tpkndyjlwhebbu


Yurong Jiang, Hang Qiu, Matthew McCartney, William G. J. Halfond, Fan Bai, Donald Grimm, Ramesh Govindan
2014 Proceedings of the 12th ACM Conference on Embedded Network Sensor Systems - SenSys '14  
of query execution.  ...  CARLOG uses Datalog to express sensor processing algorithms, but incorporates novel query optimization methods that can be used to minimize bandwidth usage, energy or latency, without sacrificing correctness  ...  We thank David Kempe for discussions on PAC cost optimization.  ... 
doi:10.1145/2668332.2668350 dblp:conf/sensys/JiangQMHBGG14 fatcat:lwipbkazvbgqxnt6l44wilvdf4

FedX: Optimization Techniques for Federated Query Processing on Linked Data [chapter]

Andreas Schwarte, Peter Haase, Katja Hose, Ralf Schenkel, Michael Schmidt
2011 Lecture Notes in Computer Science  
In experiments, we demonstrate the practicability and efficiency of our framework on a set of real-world queries and data sources from the Linked Open Data cloud.  ...  With FedX we achieve a significant improvement in query performance over state-of-the-art federated query engines.  ...  Research reported in this paper was partially supported by the German BMBF in the project CollabCloud.  ... 
doi:10.1007/978-3-642-25073-6_38 fatcat:3mgfop65s5dmbpmkterq4j2hve

RDF in the clouds: a survey

Zoi Kaoudi, Ioana Manolescu
2014 The VLDB journal  
The Resource Description Framework (RDF) pioneered by the W3C is increasingly being adopted to model data in a variety of scenarios, in particular data to be published or exchanged on the Web.  ...  parallel architectures.  ...  One of the first works providing RDFS closure computation algorithms in a parallel environment is WebPie [84] .  ... 
doi:10.1007/s00778-014-0364-z fatcat:qyp6euinnvexxlliqe2wf45ona

Row-wise parallel predicate evaluation

Ryan Johnson, Vijayshankar Raman, Richard Sidle, Garret Swart
2008 Proceedings of the VLDB Endowment  
We then evaluate partial predicates on the columns of each bank, using a novel evaluation strategy that evaluates column level equality, range tests, IN-list predicates, and conjuncts of these predicates  ...  In this paper we propose a new layout and processing technique for efficient one-pass predicate evaluation.  ...  Acknowledgements: We wish to thank Lin Qiao and Fred Reiss for many useful suggestions during the course of this work.  ... 
doi:10.14778/1453856.1453925 fatcat:voqug6tisnadziof2cqrmfwadu

Introduction to Query Processing [chapter]

Matthias Jarke, Jürgen Koch, Joachim W. Schmidt
1985 Topics in Information Systems  
The set of all Tij for a given i is called the i-th conjunction of the matrix; a query which contains only one conjunction is called a conjunctive query [ CHAN77 1.  ...  This approach can cover parallel or feedback evaluation strategies in a realistic way but the optimization effort is high.  ... 
doi:10.1007/978-3-642-82375-6_1 fatcat:frcrnj5rlnhfnbatu53pe4t7xu

SPARQL Query Optimization on Top of DHTs [chapter]

Zoi Kaoudi, Kostis Kyzirakos, Manolis Koubarakis
2010 Lecture Notes in Computer Science  
We study the problem of SPARQL query optimization on top of distributed hash tables.  ...  Existing works on SPARQL query processing in such environments have never been implemented in a real system, or do not utilize any optimization techniques and thus exhibit poor performance.  ...  Our current research is focused on the implementation and evaluation of algorithm SBV [11] , which achieves a better load balancing, in the presence of the query optimization framework that we have developed  ... 
doi:10.1007/978-3-642-17746-0_27 fatcat:qrtn2k7oqnflzb4lp6yblbaola

Batch matching of conjunctive triple patterns over linked data streams in the internet of things

Yongrui Qin, Quan Z. Sheng, Nickolas J. G. Falkner, Ali Shemshadi, Edward Curry
2015 Proceedings of the 27th International Conference on Scientific and Statistical Database Management - SSDBM '15  
The system integrates Linked Data streams generated from various data collectors and disseminates matched data to relevant data consumers based on conjunctive triple pattern queries registered in the system  ...  With CTP-automata, the proposed system can disseminate Linked Data at a speed of an order of magnitude faster than the existing approach with thousands of registered conjunctive queries.  ...  Similarly, the work in [16] focuses on optimizing the processing of conjunctive triple pattern queries, especially star-shaped group based queries individually.  ... 
doi:10.1145/2791347.2791364 dblp:conf/ssdbm/QinSFSC15 fatcat:7tgjhthhn5bhtkdbcezl7hbdji

Distributed Query Processing in an Ad-hoc Semantic Web Data Sharing System

Jing Zhou, Gregor V. Bochmann, Zhongzhi Shi
2013 2013 IEEE International Symposium on Parallel & Distributed Processing, Workshops and Phd Forum  
Additionally, we propose efficient distributed processing of SPARQL queries in such a context and explore optimization techniques that build upon distributed query processing for database systems and relational  ...  Sharing the Semantic Web data in proprietary datasets in which data is encoded in RDF triples in a decentralized environment calls for efficient support from distributed computing technologies.  ...  Therefore, ⟦P 1 ⟧ D and ⟦P 2 ⟧ D can be carried out in parallel as described in the generic query execution plan for SPARQL queries with a conjunction graph pattern (see Sect. IV-D).  ... 
doi:10.1109/ipdpsw.2013.53 dblp:conf/ipps/ZhouBS13 fatcat:566c3zwxdvb2dpybqqa3fxd4re

Optimism analysis of parallel queries in databases through multicores

P Mohankumar, P Kumaresan, J Vaideeswaran
2011 International Journal of Database Management Systems  
An optimistic analysis is made in this paper how to cover parallelism for database queries without suffering any loss and obtained desired response time.  ...  Thus it turned the research people interest how the peculiar queries for particular application can be resolved in an elapsed time slice optimistically. Ultimately it's parallelizing the process.  ...  research and providing facilities to test our design in labs.  ... 
doi:10.5121/ijdms.2011.3110 fatcat:aal433zn4bbklbxaknb5qwv5k4
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