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Automatically Improving SAT Encoding of Constraint Problems Through Common Subexpression Elimination in Savile Row [chapter]

Peter Nightingale, Patrick Spracklen, Ian Miguel
2015 Lecture Notes in Computer Science  
Common Subexpression Elimination (CSE) is a family of techniques to improve automatically the formulation of constraint satisfaction problems, which are often highly beneficial when using a conventional  ...  In this work we demonstrate that CSE has similar benefits when the reformulated constraint model is encoded to SAT and solved using a state-of-the-art SAT solver.  ...  Conclusion Common Subexpression Elimination has proven to be a valuable tool in the armoury of reformulations applied to constraint models, however hitherto there has only been limited success in applying  ... 
doi:10.1007/978-3-319-23219-5_23 fatcat:vqbw5hmwprarpgx4gym6ouxhxa

Efficient and Provable Multi-Query Optimization [article]

Tarun Kathuria, S. Sudarshan
2017 arXiv   pre-print
The problem of multi-query optimization (MQO) is to generate an optimal combined evaluation plan by computing common subexpressions once and reusing them.  ...  In this paper, instead of the conventional cost minimization problem, we treat the problem as maximizing a linear transformation of the cost function.  ...  best plan trees may not have common subexpressions.  ... 
arXiv:1512.02568v2 fatcat:i5yofiztobe6hmjjmgougfomce

Selecting subexpressions to materialize at datacenter scale

Alekh Jindal, Konstantinos Karanasos, Sriram Rao, Hiren Patel
2018 Proceedings of the VLDB Endowment  
In this paper, we focus on the problem of subexpression selection for large workloads, i.e., selecting common parts of job plans and materializing them to speed-up the evaluation of subsequent jobs.  ...  We provide an ILP-based formulation of our problem and map it to a bipartite graph labeling problem.  ...  PROBLEM FORMULATION In this section, we define ( §2.1) and formulate ( §2.2) the problem of subexpression selection, i.e., selecting common subexpressions to materialize and reuse across queries.  ... 
doi:10.14778/3192965.3192971 fatcat:pgrov7wzhrdt3imxbji7bmqhny

Re-Optimization Mvpp Using Common Subexpression For Materialized View Selection

Boontita Suchyukorn, Raweewan Auepanwiriyakul
2013 Zenodo  
In this paper we have proposed an approach to reoptimize Multiple View Processing Plan (MVPP) by using global common subexpressions.  ...  Deciding which appropriated views to be materialized is one of important problem. In order to achieve this requirement, the constructing search space close to optimal is a necessary task.  ...  In this paper, the approach to re-optimize the search space MVPP for view selection problem has been proposed by using concept of commonality of global common subexpression.  ... 
doi:10.5281/zenodo.1087264 fatcat:4ocxyj2vn5b6zaviwy36nr5mgu

Computing closest common subexpressions for view selection problems

Wugang Xu, Dimitri Theodoratos, Calisto Zuzarte
2006 Proceedings of the 9th ACM international workshop on Data warehousing and OLAP - DOLAP '06  
In this paper we propose an approach for generating candidate views for materialization for view selection problems based on the definition of the input queries.  ...  The view selection algorithms are expensive due to the size of the search space of the problem.  ...  In [13] , a general concept of common subexpression is introduced and some constraints (e.g. key/foreign key constraints) are considered.  ... 
doi:10.1145/1183512.1183527 dblp:conf/dolap/XuTZ06 fatcat:iq2z7nsfvbfonekevusc6iw37y

Developing a combinatorial model for the multiple constant multiplication

Firas Ali Jawad Al-Hasani
2015 International Journal of Engineering & Technology  
Enumerating all of the routes that start from the signal vertex and visit all the coefficients gives all the solutions of the MCM problem.  ...  The solution space contains all the possible solutions that can be obtained from using both of the common subexpression elimination (CSE) and graph dependent heuristics that traditionally used to solve  ...  In this way, subexpressions are shared by common paths which makes the problem of minimizing of the MCM as a graph traversal.  ... 
doi:10.14419/ijet.v4i4.5132 fatcat:hhdeoufnijafnaxxlq5ngcbg2e

On Solving Efficiently the View Selection Problem under Bag-Semantics [chapter]

Foto Afrati, Matthew Damigos, Manolis Gergatsoulis
2009 Lecture Notes in Business Information Processing  
In this paper, we investigate the problem of view selection for workloads of conjunctive queries under bag semantics. In particular we aim to limit the search space of candidate viewsets.  ...  This last result shows that in the case of path queries, taking query subexpressions suffice.  ...  The authors in [21] , study the problem of searching for a maximum common subexpression of a workload, while [23] proposes an algorithm for searching for maximum common subexpressions for a subclass  ... 
doi:10.1007/978-3-642-03422-0_2 fatcat:ih3hf4elizggrjt4w777oakh5y

MiniZinc with Functions [chapter]

Peter J. Stuckey, Guido Tack
2013 Lecture Notes in Computer Science  
Functional relations are ubiquitous in combinatorial problems -the Global Constraint Catalog lists 120 functional constraints.  ...  The addition of functions, with common subexpression elimination, makes the encoding of solver-specific translations much more powerful.  ...  NICTA is funded by the Australian Government as represented by the Department of Broadband, Communications and the Digital Economy and the Australian Research Council.  ... 
doi:10.1007/978-3-642-38171-3_18 fatcat:gckp7b76tnhdldtv7m2eazw7te

Cache-based Multi-query Optimization for Data-intensive Scalable Computing Frameworks [article]

Pietro Michiardi, Damiano Carra, Sara Migliorini
2018 arXiv   pre-print
By careful selection and exploitation of common (sub)expressions, while satisfying memory constraints, our method transforms a batch of queries into a new, more efficient one which avoids unnecessary recomputations  ...  To find feasible and efficient execution plans, our method uses a cost-based optimization formulation akin to the multiple-choice knapsack problem.  ...  The authors would like to thank Khoa Nguyen Trong, Duy-Hung Phan and Quang-Nhat Hoang-Xuan for the valuable discussions and contribution in the early stage of this work.  ... 
arXiv:1805.08650v1 fatcat:jxazmzgo2bfyhlmwltafnl5tly

On the Optimal Ordering of Maps, Selections, and Joins Under Factorization [chapter]

Thomas Neumann, Sven Helmer, Guido Moerkotte
2006 Lecture Notes in Computer Science  
Specifically, we look at the case where common subexpressions involving expensive UDF calls can be factored out.  ...  We examine the problem of producing the optimal evaluation order for queries containing joins, selections, and maps.  ...  As we factorize common subexpressions, we do not have to recalculate map operators that have already been computed in a (partial) plan P .  ... 
doi:10.1007/11788911_10 fatcat:xaf5xbnk5fbczd7o2doosqv5hq

Automatically improving constraint models in Savile Row

Peter Nightingale, Özgür Akgün, Ian P. Gent, Christopher Jefferson, Ian Miguel, Patrick Spracklen
2017 Artificial Intelligence  
Even an expert human may explore many alternatives in modelling a single problem. We make a number of contributions in the automated modelling and reformulation of constraint models.  ...  We introduce and describe in detail a new algorithm, X-CSE, to perform Associative-Commutative Common Subexpression Elimination (AC-CSE) in constraint problems, significantly improving existing CSE techniques  ...  In addition, Dr Jefferson is funded by a Royal Society University Research Fellowship.  ... 
doi:10.1016/j.artint.2017.07.001 fatcat:tu565j3nbrc2ragicqu5ozqczq

Materialized view maintenance and integrity constraint checking

Kenneth A. Ross, Divesh Srivastava, S. Sudarshan
1996 Proceedings of the 1996 ACM SIGMOD international conference on Management of data - SIGMOD '96  
We demonstrate that global optimization cannot, in general, be achieved by locally optimizing each materialized subview, because common subexpressions between di erent materialized subviews can allow nonoptimal  ...  Our results are particularly important for the e cient checking of assertions (complex integrity constraints) in the SQL-92 standard, since the incremental checking of such integrity constraints is known  ...  The research of Kenneth Ross was supported by a grant from the AT&T Foundation, by a David and Lucile Packard Foundation Fellowship in Science and Engineering, by a Sloan Foundation Fellowship, by NSF  ... 
doi:10.1145/233269.233361 dblp:conf/sigmod/RossSS96 fatcat:hqpez2bjjfe7lpxbb24seoidsa

Materialized view maintenance and integrity constraint checking

Kenneth A. Ross, Divesh Srivastava, S. Sudarshan
1996 SIGMOD record  
We demonstrate that global optimization cannot, in general, be achieved by locally optimizing each materialized subview, because common subexpressions between di erent materialized subviews can allow nonoptimal  ...  Our results are particularly important for the e cient checking of assertions (complex integrity constraints) in the SQL-92 standard, since the incremental checking of such integrity constraints is known  ...  The research of Kenneth Ross was supported by a grant from the AT&T Foundation, by a David and Lucile Packard Foundation Fellowship in Science and Engineering, by a Sloan Foundation Fellowship, by NSF  ... 
doi:10.1145/235968.233361 fatcat:brycahul5jaoxbulwlzfl6zqiu

Online optimization and fair costing for dynamic data sharing in a cloud data market

Ziyang Liu, Hakan Hacigümüs
2014 Proceedings of the 2014 ACM SIGMOD international conference on Management of data - SIGMOD '14  
Both problems are challenging since in the first problem, different sharings with the same operations in their plans may reuse these operations, and each sharing plan must be generated online.  ...  In the second problem, there are several factors that impact the fairness of a costing function and a straightforward mechanism won't work.  ...  For multiple sharings with common subexpressions, such as the two sharings in Example 1.1, the computation of a common subexpression can be reused so that the subexpression is only computed once.  ... 
doi:10.1145/2588555.2593679 dblp:conf/sigmod/LiuH14 fatcat:xfarlouqefhmzhk4vl44cxcfyu

Pipelining in multi-query optimization

Nilesh N. Dalvi, Sumit K. Sanghai, Prasan Roy, S. Sudarshan
2001 Proceedings of the twentieth ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '01  
Database 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.  ...  We would also like to thank all the referees for their insightful reviews which helped us in improving the quality of the paper.  ... 
doi:10.1145/375551.375561 dblp:conf/pods/DalviSRS01 fatcat:lyr7hjiarvfjtbkzhrtb2esd3m
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