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Algorithmic Aspects of Parallel Data Processing

Paraschos Koutris, Semih Salihoglu, Dan Suciu
2018 Foundations and Trends in Databases  
In Chapter 5 we discuss a few traditional aspects of parallel sorting algorithms.  ...  Similar to hashing, sorting is a core technique in database query processing, both in the sequential and in the parallel setting.  ... 
doi:10.1561/1900000055 fatcat:u5icy7htubbt7oboux4sa46mci

Empirical study of parallel SQL query execution

Kirill K. Smirnov, George A. Chernishev
2018 Proceedings of the Institute for System Programming of RAS  
In this paper we experiment with two major types of query parallelization techniques - intra and inter operator parallelism and their combinations.  ...  We evaluate these techniques applied to a query tree with a number of join operators in the multithreaded environment.  ...  Yet another pair of aspects to consider designing a distributed database system is the operator parallelization methods.  ... 
doaj:f858be568af14c45a698a7a0dd236297 fatcat:szpcxes3encszckvgj7y4lczoa

A Study of Pre-Processing Technique for Map-Matching Schemes of GPS-Enabled Vehicles

Aftab Ahmed Chandio,
2017 International Journal of Computing and Digital Systems  
In the experimental work, the results of the map-matching schemes (i.e., found in the literature review) incorporated with our proposed pre-processing technique shows better performance in aspect to the  ...  In this paper, we introduce the pre-processing technique; splitting the road network graph and processing the Single Source Shortest Path (SSSP) in synchronize parallel processing in the Hadoop environment  ...  Common types of queries can also use these results to accelerate the query processing time.  ... 
doi:10.12785/ijcds/060104 fatcat:sxtyx2rs4rhaxok7s23zrtvila

An Effective K-Nearest Neighbor Track Retrieval Algorithm

Chen Wen
2016 International Journal of Database Theory and Application  
A parallel TA algorithm in random access database is proposed, and it has effectively solved the issue of k-nearest neighbor track retrieval.  ...  Performance of this algorithm is verified through a large number of experiments.  ...  Parallel TA Algorithm In order to solve the mass data of historical tracks in kNNT, this paper proposes a parallel TA algorithm on the basis of TA algorithm by fully utilizing the parallelism of data processing  ... 
doi:10.14257/ijdta.2016.9.3.16 fatcat:umph5wybvncuxoal6rapp7bg34

Relational versus non-relational database systems for data warehousing

Carlos Ordonez, Il-Yeol Song, Carlos Garcia-Alvarado
2010 Proceedings of the ACM 13th international workshop on Data warehousing and OLAP - DOLAP '10  
flexibility and cost; as well as technical aspects like data modeling, storage, hardware, scalability, query processing, fault tolerance and data mining.  ...  Out of these proposals, distributed file systems together with MapReduce have become strong competitors to relational database systems to analyze large data sets, exploiting parallel processing.  ...  MapReduce [1, 5] is a simple parallel programming model coming from functional programming, that enables fast processing on a cluster of computers.  ... 
doi:10.1145/1871940.1871955 dblp:conf/dolap/OrdonezSG10 fatcat:e2rzwq6cwfby3j3auxykdia2tm

A Classification of Skew Effects in Parallel Database Systems [chapter]

Holger Märtens
2001 Lecture Notes in Computer Science  
For instance, partial parallelism -though often beneficial to reduce the total workload for small queries -is far more likely than full parallelism to lead to multi-processing skew.  ...  However, a systematic analysis and classification of skew does not yet exist. A taxonomy of data skew in parallel joins [14] includes the aspects of intrinsic and partition skew.  ... 
doi:10.1007/3-540-44681-8_42 fatcat:2thonnl2w5c6fmhvhopza32ism

Load and storage balanced posting file partitioning for parallel information retrieval

Yung-Cheng Ma, Chung-Ping Chung, Tien-Fu Chen
2011 Journal of Systems and Software  
Mean query processing time is estimated with popularities of keyword terms.  ...  The objective of the partitioning is to minimize storage requirement per workstation subject to a limited mean query processing time.  ...  Parallel query processing works as follows. For a given query q, the parallel query processing is to compute the answer list ANS q in parallel.  ... 
doi:10.1016/j.jss.2011.01.028 fatcat:matvtq4bazfurb654znkcogfvu

A Requirements Analysis for Parallel KDD Systems [chapter]

William A. Maniatty, Mohammed J. Zaki
2000 Lecture Notes in Computer Science  
Our analysis shows that parallel data mining solutions require the following components: parallel data mining algorithms, parallel and distributed data bases, parallel file systems, parallel I/O, tertiary  ...  This paper explores a migration path out of this bottleneck by considering an integrated hardware and software approach to parallelize data mining.  ...  The vast amount of work on parallel relational query operators, particularly parallel join algorithms, is also of relevance (Pirahesh et al. 1990 ).  ... 
doi:10.1007/3-540-45591-4_47 fatcat:ekp6fbwpufh3bd4y6o5e6syz2i

Queries over Web Services [chapter]

Efthymia Tsamoura, Anastasios Gounaris, Yannis Manolopoulos
2011 Studies in Computational Intelligence  
Different Aspects of the Problem of Optimizing WS Queries Before probing into advanced query optimization algorithms that are relevant to queries over WSs, we must first discuss the factors of the problem  ...  Three types of parallelism have been identified in parallel query processing, namely independent, partitioned and pipelined parallelism.  ... 
doi:10.1007/978-3-642-17551-0_6 fatcat:3xjcwgl57jbbtgosgzayihq7yq

Research Progress of Stream Data Query in Network Space

Yi Wu, Jianjun Zhou
2015 International Journal of Database Theory and Application  
With the development of cloud computing technology, such high parallel processing frameworks as MapReduce model sharply improve the efficiency of Skyline query process.  ...  The problem that centralized algorithm lack of processing capacity can be solved through collateral execution.  ...  International Journal of Database Theory and Application Vol. 8, No.5 (2015)  ... 
doi:10.14257/ijdta.2015.8.5.14 fatcat:2jfxpbvlgfctxe7rl24gd2hxom

Novel Distributed Query Optimization Model and Hybrid Query Optimization Algorithm

Deepak Sukheja, Umesh Kumar Singh
2013 International Journal of Computer Applications  
Query optimization in distributed databases explicitly needed in many aspects of the optimization process, this is not only increases the cost of optimization, but also changes the trade-offs involved  ...  in the optimization process significantly .This paper describes the synthetically evolution of query optimization methods from uniprocessor relational database systems to parallel database systems.  ...  and then apply hybrid query optimization algorithm in conversion and distribution phase of distributed query processing and optimization process to reduce the total cost and response time of database  ... 
doi:10.5120/13203-0461 fatcat:lgajokattvay7d7ww7xmokxqy4

Estimating the number of answers with guarantees for structured queries in p2p databases

Marcel Karnstedt, Kai-Uwe Sattler, Michael Haß, Manfred Hauswirth, Brahmananda Sapkota, Roman Schmidt
2008 Proceeding of the 17th ACM conference on Information and knowledge mining - CIKM '08  
In such systems, estimating the number of answers for structured queries can help approximating query completeness, but is especially challenging.  ...  We introduce the general approach and briefly discuss further aspects like overhead and guarantees.  ...  Based on the notion of routing graphs, the basic idea of estimating query completeness works as shown in Algorithm 1. This procedure is called every time a new reply arrives at the initiator.  ... 
doi:10.1145/1458082.1458304 dblp:conf/cikm/KarnstedtSHHSS08 fatcat:hmgkh4jeubh6npjsmxobj5ux44

OrChem - An open source chemistry search engine for Oracle®

Mark Rijnbeek, Christoph Steinbeck
2009 Journal of Cheminformatics  
Registration, indexing and searching of chemical structures in relational databases is one of the core areas of cheminformatics.  ...  OrChem provides similarity searching with response times in the order of seconds for databases with millions of compounds, depending on a given similarity cut-off.  ...  We thank the Pubchem team for assembling this great collection of molecular structures and for opening up their fingerprint definition.  ... 
doi:10.1186/1758-2946-1-17 pmid:20298521 pmcid:PMC2820495 fatcat:ukgxiena3bamvjshgyw5tf2q4i

Open issues in parallel query optimization

Waqar Hasan, Daniela Florescu, Patrick Valduriez
1996 SIGMOD record  
We provide an overview of query processing in parallel database systems and discuss several open issues in the optimization of queries for parallel machines.  ...  Given a SQL query, parallel query optimization has the goal of finding a parallel plan that delivers the query result in minimal time.  ...  Evaluation of Algorithms Two important aspects of evaluating an algorithm are the quality of the plans and the running time of the algorithm.  ... 
doi:10.1145/234889.234894 fatcat:kbvsxwxmxnhetg5adb47hx6bna

OrChem: an open source chemistry search engine for Oracle

Mark L Rijnbeek, Christoph Steinbeck
2010 Journal of Cheminformatics  
Registration, indexing and searching of chemical structures in relational databases is one of the core areas of cheminformatics.  ...  OrChem provides similarity searching with response times in the order of seconds for databases with millions of compounds, depending on a given similarity cut-off.  ...  We thank the Pubchem team for assembling this great collection of molecular structures and for opening up their fingerprint definition.  ... 
doi:10.1186/1758-2946-2-s1-p28 pmcid:PMC2867161 fatcat:iqczh6y5orgglaaiudmauaqpmi
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