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Semantic query optimization for object queries
1995Semantic query optimization is an approach to query optimization that utilizes semantic knowledge to reformulate a query into one that would generate the same set of answers in a more efficient way. The semantic query optimization becomes more important in OODB systems where object queries are complex due to the presence of object-oriented concepts ...
Young-Whun Lee, Suk I. Yoo
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Optimization of schemaSQL queries
Proceedings 2001 International Database Engineering and Applications Symposium, 2002We study the optimization of schemaSQL and schemaSQL-like languages. Our starting point is an extended relational algebra which can be used to implement schemaSQL and similar languages. We study transformation (rewrite) rules for the extended algebra which are used in a prototype cost-based optimizer for the rewriting of expressions into more efficient
Keir B. Davis, Fereidoon Sadri
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2009
Complex queries are becoming commonplace with the growing use of decision support systems. These complex queries often have a lot of common sub-expressions, either within a single query, or across multiple such queries. The focus of this work is to speed up query execution by exploiting these common subexpressions.
Prasan Roy, S. Sudarshan
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Complex queries are becoming commonplace with the growing use of decision support systems. These complex queries often have a lot of common sub-expressions, either within a single query, or across multiple such queries. The focus of this work is to speed up query execution by exploiting these common subexpressions.
Prasan Roy, S. Sudarshan
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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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Bringing order to query optimization [PDF]
ACM SIGMOD Record, 2002 A variety of developments combine to highlight the need for respecting order when manipulating relations. For example, new functionality is being added to SQL to support OLAP-style querying in which order is frequently an important aspect. The set- or multiset-based frameworks for query optimization that are currently being taught to database students ...
Giedrius Slivinskas +2 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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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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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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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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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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