Results 11 to 20 of about 200,383 (240)
Algebraic optimization of recursive queries [PDF]
, 1992 Over the past few years, much attention has been paid to deductive databases. They offer a logic-based interface, and allow formulation of complex recursive queries.
Apers, Peter M.G. +2 more
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Query Optimization in an OODBMS [PDF]
, 1993 It is clearly crucial for the success of object—oriented databases to find efficient implementations that improve on the performance of relational systems, rather than being powerful in terms of modeling and features, but just too slow to be used. This paper describes the mapping of COCOON to DASDBS, a nested relational database kernel system, as an ...
Christian Rich, Marc H. Scholl
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Optimal Divide and Query [PDF]
, 2011 This work has been partially supported by the Spanish Ministerio de Ciencia e Innovación under grant TIN2008-06622-C03-02 and by the Generalitat Valenciana under grant PROMETEO/2011/052.
David Insa, Josep Silva
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Apache Calcite: A Foundational Framework for Optimized Query Processing Over Heterogeneous Data Sources [PDF]
, 2018 Apache Calcite is a foundational software framework that provides query processing, optimization, and query language support to many popular open-source data processing systems such as Apache Hive, Apache Storm, Apache Flink, Druid, and MapD.
Begoli, Edmon +4 more
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Simulation Subsumption or Déjà vu on the Web [PDF]
, 2008 Simulation unification is a special kind of unification adapted to retrieving semi-structured data on the Web. This article introduces simulation subsumption, or containment, that is, query subsumption under simulation unification. Simulation subsumption
A. Klug +6 more
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Parametric query optimization [PDF]
The VLDB Journal The International Journal on Very Large Data Bases, 1997 In most database systems, the values of many important run-time parameters of the system, the data, or the query are unknown at query optimization time. Parametric query optimization attempts to identify at compile time several execution plans, each one of which is optimal for a subset of all possible values of the run-time parameters. The goal is that
Yannis E. Ioannidis +3 more
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Proceedings of the 2019 International Conference on Management of Data, 2019 In recent decades, we observed the rapid growth of several big data platforms. Each of them is designed for specific demands. For instance, Spark can efficiently process iterative queries, while Storm is designed for in-memory processing. In this context, the complexity of these distributed systems make it much harder to develop rigorous cost models ...
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On the Complexity of Query Result Diversification [PDF]
, 2013 Query result diversification is a bi-criteria optimization problem for ranking query results. Given a database D, a query Q and a positive integer k, it is to find a set of k tuples from Q(D) such that the tuples are as relevant as possible to the query,
Abiteboul S. +35 more
core +5 more sources
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
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XPath Whole Query Optimization
, 2010 Previous work reports about SXSI, a fast XPath engine which executes tree automata over compressed XML indexes. Here, reasons are investigated why SXSI is so fast.
Maneth, Sebastian, Nguyen, Kim
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