Results 241 to 250 of about 3,172,290 (290)
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1995
An approach to query processing in object-oriented stores supporting physical data independence is proposed in this Chapter. In particular, the problem of query optimisation (i e finding efficient execution plans for declarative queries) is investigated. A set of rewrite rules has been defined in order to allow an algebraic optimisation phase.
Rabitti F, Benedetti L, Demi F
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An approach to query processing in object-oriented stores supporting physical data independence is proposed in this Chapter. In particular, the problem of query optimisation (i e finding efficient execution plans for declarative queries) is investigated. A set of rewrite rules has been defined in order to allow an algebraic optimisation phase.
Rabitti F, Benedetti L, Demi F
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Processing Implication on Queries
IEEE Transactions on Software Engineering, 1989The ability to quickly determine how to derive a given query from a set of prestored fragments is highly demanded in many database applications, especially in distributed database systems, where the communication cost is a major concern. The main difficulty in solving this problem lies in the implication problem given two predicates σQ and σT, can σQ ...
Sun, Xian-he +2 more
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ACM Computing Surveys, 1984
In this paper, various techniques for optimizing queries in distributed databases are presented. Although no attempt is made to cover all proposed algorithms on this topic, quite a few ideas extracted from existing algorithms are outlined. It is hoped that large-scale experiments will be conducted to verify the usefulness of these ideas and that they ...
Clement T. Yu, C. C. Chang
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In this paper, various techniques for optimizing queries in distributed databases are presented. Although no attempt is made to cover all proposed algorithms on this topic, quite a few ideas extracted from existing algorithms are outlined. It is hoped that large-scale experiments will be conducted to verify the usefulness of these ideas and that they ...
Clement T. Yu, C. C. Chang
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Query Relaxation in Cooperative Query Processing
2009This chapter explores new trends of query relaxation strategies that allow to implement a cooperative query processing paradigm. This new paradigm is based on the belief that the user has an idea of what he/she wants and the system has to automatically lead him/her to formulate meaningful queries by relaxing query constraints.
D'Ulizia Arianna +2 more
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Query Processing in Spatial-Query-by-Sketch
Journal of Visual Languages & Computing, 1997Abstract Spatial-Query-by-Sketch is the design of a query language for geographic information systems. It allows a user to formulate a spatial query by drawing the desired configuration with a pen on a touch-sensitive computer screen and translates this sketch into a symbolic representation that can be processed against a geographic database.
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Proceedings of the VLDB Endowment, 2019
Many applications ingest data in an intermittent, yet largely predictable, pattern. Existing systems tend to ignore how data arrives when making decisions about how to update (or refresh) an ongoing query. To address this shortcoming we propose a new query processing paradigm, Intermittent Query Processing (IQP), that bridges query execution and ...
Dixin Tang +4 more
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Many applications ingest data in an intermittent, yet largely predictable, pattern. Existing systems tend to ignore how data arrives when making decisions about how to update (or refresh) an ongoing query. To address this shortcoming we propose a new query processing paradigm, Intermittent Query Processing (IQP), that bridges query execution and ...
Dixin Tang +4 more
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Computer, 2007
Sensors produce large streams of raw events while instrumenting environments such as computer systems, communications networks, physical spaces, and human organizations. Extracting meaningful and actionable information from these events, however, remains a challenge.
George Cybenko, Vincent H. Berk
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Sensors produce large streams of raw events while instrumenting environments such as computer systems, communications networks, physical spaces, and human organizations. Extracting meaningful and actionable information from these events, however, remains a challenge.
George Cybenko, Vincent H. Berk
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2011 IEEE 27th International Conference on Data Engineering, 2011
In the context of data management, robustness is usually associated with resilience against failure, recovery, redundancy, disaster preparedness, etc. Robust query processing, on the other hand, is about robustness of performance and of scalability. It is more than progress reporting or predictability.
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In the context of data management, robustness is usually associated with resilience against failure, recovery, redundancy, disaster preparedness, etc. Robust query processing, on the other hand, is about robustness of performance and of scalability. It is more than progress reporting or predictability.
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1993
In this chapter, we have examined the various issues and techniques encountered in parallel query processing. The methods used to exploit query parallelism are divided into three categories: namely intra- operator, inter- operator, and inter- query parallelism.
Philip S. Yu +3 more
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In this chapter, we have examined the various issues and techniques encountered in parallel query processing. The methods used to exploit query parallelism are divided into three categories: namely intra- operator, inter- operator, and inter- query parallelism.
Philip S. Yu +3 more
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Extending query languages for in-network query processing
Proceedings of the 10th ACM International Workshop on Data Engineering for Wireless and Mobile Access, 2011Sensor networks have become ubiquitous and their proliferation in day-to-day life provides new research challenges. Sensors deployed at forest sites, high performance facilities, or areas striken by environmental, or other, phenomena, are only a few representative examples.
George Valkanas +4 more
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