Results 1 to 10 of about 327,421 (217)
A technique for parallel query optimization using MapReduce framework and a semantic-based clustering method [PDF]
Query optimization is the process of identifying the best Query Execution Plan (QEP). The query optimizer produces a close to optimal QEP for the given queries based on the minimum resource usage.
Elham Azhir+4 more
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Pipelining in multi-query optimization [PDF]
AbstractDatabase systems frequently have to execute a set of related queries, which share several common subexpressions. Multi-query optimization exploits this, by finding evaluation plans that share common results. Current approaches to multi-query optimization assume that common subexpressions are materialized. Significant performance benefits can be
DALVI, NILESH N+3 more
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DISTRIBUTED QUERY OPTIMIZATION [PDF]
The need for the distributed systems has been determined by the type of business developed by companies with offices geographically distributed where the specific organizational structure promotes a decentralized business model.
Nicoleta IACOB
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Query optimization at the crossroads [PDF]
Surajit Chaudhuri
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Optimization of correlate subquery based on distributed database
Subquery is widely used in database. It can be divided into related subquery and non-related subquery according to whether it is dependent on the table of the parent query.
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Query Refinement into Information Retrieval Systems: An Overview
Query, expressing the user need and requirement, has an important role, in an information retrieval system, for reaching a high accuracy search. In this paper, we present an overview of the different refinement operations that the query may undergo, in ...
Mawloud Mosbah
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Semantic Optimization of Conjunctive Queries [PDF]
This work deals with the problem of semantic optimization of the central class of conjunctive queries (CQs). Since CQ evaluation is NP-complete, a long line of research has focussed on identifying fragments of CQs that can be efficiently evaluated.
Barcelo P.+3 more
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Optimal Divide and Query [PDF]
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.
Insa Cabrera, David+1 more
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Query Optimization in Teradata Warehouse
The time necessary for data processing is becoming shorter and shorter nowadays. This thesis presents a definition of the active data warehousing (ADW) paradigm.
Agnieszka Gosk
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Query Optimization in an OODBMS [PDF]
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 ...
Rich, Christian, Scholl, Marc H.
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