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Optimization and evaluation of disjunctive queries
IEEE Transactions on Knowledge and Data Engineering, 2000It is striking that the optimization of disjunctive queries-i.e. those which contain at least one OR-connective in the query predicate-has been vastly neglected in the literature, as well as in commercial systems. In this paper, we propose a novel technique, called bypass processing, for evaluating such disjunctive queries.
Claussen, Jens +4 more
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2005
We propose and solve the optimal-location query in spatial databases. Given a set S of sites, a set O of weighted objects, and a spatial region Q, the optimal-location query returns a location in Q with maximum influence. Here the influence of a location l is the total weight of its RNNs, i.e.
Yang Du, Donghui Zhang, Tian Xia 0001
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We propose and solve the optimal-location query in spatial databases. Given a set S of sites, a set O of weighted objects, and a spatial region Q, the optimal-location query returns a location in Q with maximum influence. Here the influence of a location l is the total weight of its RNNs, i.e.
Yang Du, Donghui Zhang, Tian Xia 0001
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Query Optimization in Database Systems
ACM Computing Surveys, 1984Summary: Efficient methods of processing unanticipated queries are a crucial prerequisite for the success of generalized database management systems. A wide variety of approaches to improve the performance of query evaluation algorithms have been proposed: logic-based and semantic transformations, fast implementations of basic operations, and ...
Matthias Jarke, Jürgen Koch
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Semantic query optimization for tree and chain queries
IEEE Transactions on Knowledge and Data Engineering, 1994Semantic query optimization, or knowledge-based query optimization, has received increasing interest in recent years. The authors provide an effective and systematic approach to optimizing queries by appropriately choosing semantically equivalent transformations.
Wei Sun 0002, Clement T. Yu
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Stored queries—a data organization for query optimization
Data & Knowledge Engineering, 1988Abstract Queries stored together with their actual responses give a possibility of improvement of database system performance regardless of the complexities of user requests and the data model employed. The main properties of such a data organization as well as its essential problems are outlined, particularly the problem of updating stored queries ...
Wiktor Rzeczkowski, Kazimierz Subieta
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Extensible Query Optimizers in Practice
Foundations and Trends in DatabasesThe performance of a query crucially depends on the ability of the query optimizer to choose a good execution plan from a large space of alternatives. With the discovery of algebraic transformation rules and the emergence of new applicationspecific contexts, extensibility has become a key requirement for query optimizers.
Bailu Ding +2 more
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Query Optimization for a Graph Database with Visual Queries
2006We have constructed a graph database system where a query can be expressed intuitively as a diagram. The query result is also visualized as a diagram based on the intrinsic relationship among the returned data. In this database system, CORAL plays the role of a query execution engine to evaluate queries and deduce results.
Greg Butler +3 more
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Query Optimization for Ontology-Mediated Query Answering
Proceedings of the ACM Web Conference 2024Ontology-mediated query answering (OMQA) consists in asking database queries on knowledge bases (KBs); a KB is a set of facts called the KB's database, which is described by domain knowledge called the KB's ontology. A widely-investigated OMQA technique is FO-rewriting: every query asked on a KB is reformulated w.r.t.
El Husseini, Wafaa +3 more
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Proceedings of the 2009 ACM SIGMOD International Conference on Management of data, 2009
Query Optimization is expected to produce good execution plans for complex queries while taking relatively small optimization time. Moreover, it is expected to pick the execution plans with rather limited knowledge of data and without any additional input from the application.
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Query Optimization is expected to produce good execution plans for complex queries while taking relatively small optimization time. Moreover, it is expected to pick the execution plans with rather limited knowledge of data and without any additional input from the application.
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Data dependencies for query optimization: a survey
VLDB Journal, 2021Thorsten Papenbrock +2 more
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