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The Vertica Query Optimizer: The case for specialized query optimizers
2014 IEEE 30th International Conference on Data Engineering, 2014The Vertica SQL Query Optimizer was written from the ground up for the Vertica Analytic Database. Its design and the tradeoffs we encountered during its implementation argue that the full power of novel database systems can only be realized with a carefully crafted custom Query Optimizer written specifically for the system in which it operates.
Nga Tran 0001 +4 more
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Query scheduling in multi query optimization
Proceedings 2001 International Database Engineering and Applications Symposium, 2002Complex queries are becoming commonplace, with the growing use of decision support systems. Decision support queries often have a lot of common sub-expressions within each query, and queries are often run as a batch. Multi query optimization aims at exploiting common sub-expressions, to reduce the evaluation cost of queries, by computing them once and ...
GUPTA, A, SUDARSHAN, S, VISHWANATHAN, S
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Multidatabase Query Optimization
Distributed and Parallel Databases, 1997A multidatabase system (MDBS) allows the users to simultaneously access heterogeneous, and autonomous databases using an integrated schema and a single global query language. The query optimization problem in MDBSs is quite different from the query optimization problem in distributed homogeneous databases due to schema heterogeneity and autonomy of ...
Cem Evrendilek +3 more
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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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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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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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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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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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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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