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Multi-Join Continuous Query Optimization: Covering the Spectrum of Linear, Acyclic, and Cyclic Queries [chapter]

Venkatesh Raghavan, Yali Zhu, Elke A. Rundensteiner, Daniel Dougherty
2009 Lecture Notes in Computer Science  
To handle the entire spectrum of query shapes from acyclic to cyclic we propose a Q-Aware approach that selects the optimization algorithm used for generating the join order, based on the shape of the  ...  However, these techniques are known to produce optimal plans only for linear and star shaped join queries.  ...  Spectrum of Linear, Acyclic and Cyclic Queries In any streaming domain many flavors of join graphs from cyclic to acyclic may coexist.  ... 
doi:10.1007/978-3-642-02843-4_11 fatcat:tcg2sgwst5g2bawnrmfhkg4tui

Optimizing Subgraph Queries by Combining Binary and Worst-Case Optimal Joins [article]

Amine Mhedhbi, Semih Salihoglu
2019 arXiv   pre-print
We study the problem of optimizing subgraph queries using the new worst-case optimal join plans.  ...  The core problem in optimizing worst-case optimal plans is to pick an ordering of the query vertices to match.  ...  are not efficient for acyclic and sparsely cyclic queries.  ... 
arXiv:1903.02076v2 fatcat:svrnitxjcfaxhluryexcxcva6i

Distributed Evaluation of Subgraph Queries Using Worstcase Optimal LowMemory Dataflows [article]

Khaled Ammar, Frank McSherry, Semih Salihoglu, Manas Joglekar
2018 arXiv   pre-print
We present the first approach that (i) performs worst-case optimal computation and communication, (ii) maintains a total memory footprint linear in the number of input edges, and (iii) scales down per-worker  ...  We study the problem of finding and monitoring fixed-size subgraphs in a continually changing large-scale graph.  ...  This amount of communication cost is always O(M axOutQ) but w is only 1 for acyclic queries, so for any cyclic query the memory requirements of GYM is superlinear in IN.  ... 
arXiv:1802.03760v1 fatcat:cjlrsnng3zep3k2m3sequqpzxm

Optimizing Compilation and Computational Complexity of Constraint Handling Rules [chapter]

Jon Sneyers
2009 Lecture Notes in Computer Science  
In the second part, we improve the state of the art by proposing and implementing several compiler optimizations.  ...  We confirm experimentally that these optimizations improve both the time and space complexity of CHR programs.  ...  Join graphs are cyclic or acyclic. Example 33 (cyclic and acyclic join graphs).  ... 
doi:10.1007/978-3-642-02846-5_41 fatcat:ywwhwcnysbea3alkxbrz7ppfxe

NeuroCard: One Cardinality Estimator for All Tables [article]

Zongheng Yang, Amog Kamsetty, Sifei Luan, Eric Liang, Yan Duan, Xi Chen, Ion Stoica
2020 arXiv   pre-print
Query optimizers rely on accurate cardinality estimates to produce good execution plans.  ...  Despite decades of research, existing cardinality estimators are inaccurate for complex queries, due to making lossy modeling assumptions and not capturing inter-table correlations.  ...  ACKNOWLEDGMENTS We thank Joe Hellerstein for fruitful discussions and guidance, and Michael Whittaker, Richard Liaw, and Chenggang Wu for their insightful comments on this paper.  ... 
arXiv:2006.08109v2 fatcat:hdjtxxeduzhwjdjxa4uamgtlqi

Ranked Enumeration of Join Queries with Projections [article]

Shaleen Deep, Xiao Hu, Paraschos Koutris
2022 arXiv   pre-print
Our main result shows that for any acyclic query, it is possible to obtain a near-linear (in the size of the database) delay algorithm after only a linear time preprocessing step for two important ranking  ...  Recent work has made considerable progress in identifying optimal algorithms for ranked enumeration of join queries that do not contain any projections.  ...  We also thank Wim Martens for the reference [15] that motivates the study of star queries.  ... 
arXiv:2201.05566v2 fatcat:gpykwdnoxrdg5ofu32ehlag5zy

Adaptive query processing

A. Deshpande, J. M. Hellerstein, V. Raman
2006 Proceedings of the 2006 ACM SIGMOD international conference on Management of data - SIGMOD '06  
In this survey paper, we identify many of the common issues, themes, and approaches that pervade this work, and the settings in which each piece of work is most appropriate.  ...  that the traditional optimize-then-execute paradigm is insufficient.  ...  We are also grateful to our editor, Joe Hellerstein, and the anonymous reviewers of this article for their constructive criticism of the earlier drafts of the article.  ... 
doi:10.1145/1142473.1142603 dblp:conf/sigmod/DeshpandeHR06 fatcat:geklxibgbzdjtix2axmtuhuewu

Flexible and extensible preference evaluation in database systems

Justin J. Levandoski, Ahmed Eldawy, Mohamed F. Mokbel, Mohamed E. Khalefa
2013 ACM Transactions on Database Systems  
We also experimentally study the strengths and weaknesses of an implementation of Flex-Pref in PostgreSQL over a range of single -table and multi-table preference queries.  ...  This paper also provides a query optimization framework for FlexPref, as well as a theoretical framework that defines the properties a preference method must exhibit to be implemented in FlexPref.  ...  We chose these case studies carefully to cover a wide spectrum of preference methods.  ... 
doi:10.1145/2508020.2493268 fatcat:a3gsz3ewufd4ddusu6g7pxbipy

The Stratosphere platform for big data analytics

Alexander Alexandrov, Rico Bergmann, Stephan Ewen, Johann-Christoph Freytag, Fabian Hueske, Arvid Heise, Odej Kao, Marcus Leich, Ulf Leser, Volker Markl, Felix Naumann, Mathias Peters (+6 others)
2014 The VLDB journal  
Stratosphere brings together a unique set of features that allow the expressive, easy, and efficient programming of analytical applications at very large scale.  ...  Acknowledgments We would like to thank the Master students that worked on the Stratosphere project and implemented many components of the system: Thomas Bodner, Christoph Brücke, Erik Nijkamp, Max Heimel  ...  of iterative (cyclic) PACT programs (Sect. 5.3).  ... 
doi:10.1007/s00778-014-0357-y fatcat:ficnpssbvjdatjs3gewa4jdd7m

29th International Conference on Data Engineering [book of abstracts]

2013 2013 IEEE 29th International Conference on Data Engineering Workshops (ICDEW)  
This information is sufficient to enumerate a large fraction of the search space covered by conventional RDBMS optimizers including filter and aggregation push-down, bushy join orders, and choice of physical  ...  A KOR query is to find a route such that it covers a set of user-specified keywords, a specified budget constraint is satisfied, and an objective score of the route is optimized.  ...  These volunteers welcome participants, give directions, help in the sessions and on the registration desk, and generally make sure the conference is running smoothly.  ... 
doi:10.1109/icdew.2013.6547409 fatcat:wadzpuh3b5htli4mgb4jreoika

Covering the Relational Join [article]

Shi Li and Sai Vikneshwar Mani Jayaraman and Atri Rudra
2020 arXiv   pre-print
In this paper, we initiate a theoretical study of what we call the join covering problem. We are given a natural join query instance Q on n attributes and m relations (R_i)_i ∈ [m].  ...  We consider the combinatorial version of the join covering problem, where our goal is to determine the worst-case |T_Q, Δ| in terms of the structure of Q and value of Δ.  ...  SVMJ thanks MSR for hospitality, where a part of this work was done.  ... 
arXiv:2003.09537v1 fatcat:47gthdfjrjf5blxln3bwscvzsu

Performing Bayesian Risk Aggregation using Discrete Approximation Algorithms with Graph Factorization [article]

Peng Lin
2015 arXiv   pre-print
The first algorithm operates on a subset of the general problem, with an emphasis on convolution problems, in the presence of continuous and discrete variables (so called hybrid models) and the second  ...  Risk aggregation is a popular method used to estimate the sum of a collection of financial assets or events, where each asset or event is modelled as a random variable.  ...  Differed from IJGP, TRC algorithm operates on an acyclic graph (and its join graph has no cyclic propagation of variables), which does not need to worry about cyclic graph based problems.  ... 
arXiv:1506.01056v1 fatcat:foskcu5b7vgmzfkkkhr2ubehxi

Misper-Bayes: A Bayesian Network Model for Missing Person Investigations

Denis Reilly, Mark Taylor, Paul Fergus, Carl Chalmers, Steven Thompson
2021 IEEE Access  
Such rearrangements allow queries to be satisfied in linear-time methods by identifying a subgraph of the original graph relevant to the query [17] . IV. DESIGN AND IMPLEMENTATION A.  ...  such rearrangements allow queries to be satisfied in linear-time.  ...  Typically, misper cases require a multi-agency approach with input from Police, Psychologists, Health-care professionals, family members and friends, to name but a few.  ... 
doi:10.1109/access.2021.3069081 fatcat:fv7xzk7lvjb4rdoxufpvgbl7kq

Learning to Sample: Counting with Complex Queries [article]

Brett Walenz, Stavros Sintos, Sudeepa Roy, Jun Yang
2019 arXiv   pre-print
For such queries, traditional sampling techniques may not be applicable due to the complexity of the filter preventing sampling over joins, and sampling after the join may not be feasible due to the cost  ...  of computing the full join.  ...  This problem has received much attention over the years, with representative works such as ripple join [7] , wander-join [17] , and more recently, sampling multi-way acyclic and cyclic joins [26] .  ... 
arXiv:1906.09335v3 fatcat:h7mxha7vnranxg77e3yfg67prq

Subject index volumes 1–200

1999 Theoretical Computer Science  
, 344 the k-adjacent derivations, 3025 generator for a family of linear indexed languages, 622 generator of a Horn spectrum, 1546 the family of context-free languages, 758 generator problem, 1546  ...  operator, 1232 spectral analysis of stochastic matrices, 3839 characteristics of transfer operators, 3659 expansion, 2386 spectrum, 2377,2389 linear time-branching time -, 3389 spectrum of a  ... 
doi:10.1016/s0304-3975(98)00319-3 fatcat:s22ud3iiqjht7lfbtc3zctk7zm
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