Results 41 to 50 of about 327,421 (217)
Optimizing the Performance of Data Warehouse by Query Cache Mechanism
IEEE Access, 2022 Fast access of data from Data Warehouse (DW) is a need for today’s Business Intelligence (BI). In the era of Big Data, the cache is regarded as one of the most effective techniques to improve the performance of accessing data.
Ch Anwar Ul Hassan +6 more
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QIACO: A Quantum Dynamic Cost Ant System for Query Optimization in Distributed Database
IEEE Access, 2021 Query optimization is considered as the most significant part in a model of distributed database. The optimizer tries to find an optimal join order, which reduces the query execution cost. Several factors may affect the cost of query execution, including
Sayed A. Mohsin +2 more
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Minimization of data base query's conditions: evoluation of efficiency
Труды Института системного программирования РАН, 2018 This paper describes enhanced algorisms of query lexical optimization. These algorisms detect and remove redundant conditions from query restriction to simplify it.
N. A. Mendkovich, S. D. Kuznetsov
doaj
Bitvector-aware Query Optimization for Decision Support Queries (extended version) [PDF]
arXiv, 2020 Bitvector filtering is an important query processing technique that can significantly reduce the cost of execution, especially for complex decision support queries with multiple joins. Despite its wide application, however, its implication to query optimization is not well understood.
arxiv
Query Optimization in Distributed Database Based on Improved Artificial Bee Colony Algorithm
Applied SciencesQuery optimization is one of the key factors affecting the performance of database systems that aim to enact the query execution plan with minimum cost. Particularly in distributed database systems, due to the multiple copies of the data that are stored ...
Yan Du, Zhi Cai, Zhiming Ding
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Performance Evaluation of Query Plan Recommendation with Apache Hadoop and Apache Spark
Mathematics, 2022 Access plan recommendation is a query optimization approach that executes new queries using prior created query execution plans (QEPs). The query optimizer divides the query space into clusters in the mentioned method.
Elham Azhir +3 more
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New algorithms for query modifications
Моделирование и анализ информационных систем, 2009 New algorithms for query modifications are proposed. These algorithms involve the lexical optimization based on the mathematical transformations that have never been used for the query optimization before.
S. D. Kuznetsov, N. A. Mendkovich
doaj
SQL UŽKLAUSŲ OPTIMIZAVIMO TYRIMAS = SQL QUERY OPTIMIZATION RESEARCH
Taikomieji tyrimai studijose ir praktikoje, 2017 Although scientific literature studies different aspects of SQL query optimization the major part of researches is limited to the theoretical analysis of problems.
Jurgita Lieponienė
doaj
Foundations of SPARQL query optimization
Proceedings of the 13th International Conference on Database Theory, 2010 The SPARQL query language is a recent W3C standard for processing RDF data, a format that has been developed to encode information in a machine-readable way. We investigate the foundations of SPARQL query optimization and (a) provide novel complexity results for the SPARQL evaluation problem, showing that the main source of complexity is operator ...
Georg Lausen +2 more
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Query optimization for dynamic imputation [PDF]
Proceedings of the VLDB Endowment, 2017 Missing values are common in data analysis and present a usability challenge. Users are forced to pick between removing tuples with missing values or creating a cleaned version of their data by applying a relatively expensive imputation strategy. Our system, ImputeDB, incorporates imputation into a cost-based query optimizer, performing necessary ...
Cambronero, José +3 more
openaire +3 more sources