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Foundations and Trends in Databases
This survey presents recent progress on using machine learning techniques to improve query optimizers in database systems. Centering around a generic paradigm of learned query optimizers, this survey covers several lines of effort on rebuilding or aiding important components in query optimizers (i.e., cardinality estimators, cost models, and plan ...
Bolin Ding, Rong Zhu, Jingren Zhou 0001
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This survey presents recent progress on using machine learning techniques to improve query optimizers in database systems. Centering around a generic paradigm of learned query optimizers, this survey covers several lines of effort on rebuilding or aiding important components in query optimizers (i.e., cardinality estimators, cost models, and plan ...
Bolin Ding, Rong Zhu, Jingren Zhou 0001
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Progressive Query Optimization for Federated Queries
2006Database Management Systems (DBMS) perform query plan selection by mathematically modeling the execution cost of candidate execution plans and choosing the cheapest query execution plan (QEP) according to that cost model. The cost model requires accurate estimates of the sizes of intermediate results of all steps in the QEP.
Stephan Ewen +3 more
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Journal of Algorithms, 1993
Summary: Let \(\Gamma_ 0\) be a set of \(n\) halfspaces in \(E^ d\) (where the dimension \(d\) is fixed) and let \(m\) be a parameter, \(n\leq m\leq n^{\lfloor d/2\rfloor}\). We show that \(\Gamma_ 0\) can be preprocessed in time and space \(0(m^{1+\delta}\)) (for any fixed \(\delta>0\)) so that given a vector \(c\in E^ d\) and another set \(\Gamma_ q\)
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Summary: Let \(\Gamma_ 0\) be a set of \(n\) halfspaces in \(E^ d\) (where the dimension \(d\) is fixed) and let \(m\) be a parameter, \(n\leq m\leq n^{\lfloor d/2\rfloor}\). We show that \(\Gamma_ 0\) can be preprocessed in time and space \(0(m^{1+\delta}\)) (for any fixed \(\delta>0\)) so that given a vector \(c\in E^ d\) and another set \(\Gamma_ q\)
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Proceedings of 16th International Conference on Data Engineering (Cat. No.00CB37073), 2002
We demonstrate a Web Query Optimizer (WQO) within an architecture of mediators and wrappers, for WebSources of limited capability in a wide area environment. The WQO has several innovative features, including a CBR (capability based rewriting) tool, an enhanced randomized relational optimizer extended to a Web environment, and a WebWrapper cost model ...
Vladimir Zadorozhny +4 more
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We demonstrate a Web Query Optimizer (WQO) within an architecture of mediators and wrappers, for WebSources of limited capability in a wide area environment. The WQO has several innovative features, including a CBR (capability based rewriting) tool, an enhanced randomized relational optimizer extended to a Web environment, and a WebWrapper cost model ...
Vladimir Zadorozhny +4 more
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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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An architecture for query optimization
Proceedings of the 1982 ACM SIGMOD international conference on Management of data - SIGMOD '82, 1982We describe an optimizer for relational queries to databases stored as flat files and Codasyl networks. We include sophisticated manipulations on a broad range of direct access structures (DAS's). To achieve this with minimum additional code, we allow operations like sort, scan, and join to apply to DAS's, and categorize indexes and other DAS's in ...
Arnon Rosenthal, David S. Reiner
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Multiobjective query optimization
Proceedings of the twentieth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems, 2001The optimization of queries in distributed database systems is known to be subject to delicate trade-offs. For example, the Mariposa database system allows users to specify a desired delay-cost tradeoff (that is, to supply a decreasing function u(d), specifying how much the user is willing to pay in order to receive the query results within time d ...
Christos H. Papadimitriou +1 more
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Parallelizing query optimization
Proceedings of the VLDB Endowment, 2008Many commercial RDBMSs employ cost-based query optimization exploiting dynamic programming (DP) to efficiently generate the optimal query execution plan. However, optimization time increases rapidly for queries joining more than 10 tables.
Wook-Shin Han +4 more
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Query Optimization for Database-Returning Queries
Proceedings of the ACM on Management of DataRecently, the novel concept of database-returning SQL queries (DRQs) was introduced. Instead of a single, (potentially) denormalized result table, DRQs return an entire subdatabase with a single SQL query. This subdatabase represents a subset of the original database, reduced to the relations, tuples, and attributes that contribute
Simon Rink, Jens Dittrich
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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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