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Main memory evaluation of recursive queries on multicore machines

Mohan Yang, Carlo Zaniolo
2014 2014 IEEE International Conference on Big Data (Big Data)  
. • PageRank, transitive closure, community discovery, network centrality, etc.  ...  evaluation of transitive closure query on multicore machines.  ...  Related Work • et al., 1993] Transitive Closure (TC) Consider a relation arc(X, Y) that represents the edges of a directed graph, the transitive closure of arc is a relation tc(X, Y) such that it contains  ... 
doi:10.1109/bigdata.2014.7004240 dblp:conf/bigdataconf/YangZ14 fatcat:dubxbod2hrd2xb2pn3x3plpluy

Bounded conjunctive queries

Yang Cao, Wenfei Fan, Tianyu Wo, Wenyuan Yu
2014 Proceedings of the VLDB Endowment  
We show that these problems range from quadratic-time to NP-complete, and develop efficient (heuristic) algorithms for them.  ...  We experimentally verify that our algorithms substantially reduce the cost of query evaluation.  ...  Exp-2: Efficiency. The second set of experiments evaluated the efficiency of our algorithms BCheck, EBCheck, findDP h and QPlan on queries and access schemas for each of TFACC, MOT and TPCH.  ... 
doi:10.14778/2732977.2732996 fatcat:tix6hucwazapvnocixmesegodi

A probabilistic view of Datalog parallelization

Sérgio Lifschitz, Victor Vianu
1998 Theoretical Computer Science  
The analysis is confirmed by experimental results on randomly generated data.  ...  Ratio of the total cost of the parallel algorithm and the cost of the sequential algorithm, for (a) and (d) linear transitive closure queries, (b) and (e) quadratic transitive closure queries, (c) and  ...  and the cost of the sequential algorithm, for (c) linear transitive closure queries, (d) quadratic transitive closure queries and (e) same generation queries, all on complete binary trees.  ... 
doi:10.1016/s0304-3975(97)00091-1 fatcat:ib2qtagn4zfcdcorpx7z2okwb4

Employing complex polyhierarchical ontologies and promoting interoperability of i2b2 data systems

James Richard Campbell, Walter Scott Campbell, Hubert Hickman, Jay Pedersen, James McClay
2015 AMIA Annual Symposium Proceedings  
We hypothesized that an alternative approach employing transitive closure tables (TC) could lead to more accurate, efficient and interoperable search tools for i2b2.  ...  Use of transitive closure tables in metadata can promote network query interoperability.  ...  Due to the relative simplicity of metadata creation from a transitive closure table for the use case of subsumption queries, we have discussed the publication of a transitive closure table for US Edition  ... 
pmid:26958167 pmcid:PMC4765692 fatcat:tkxnmxdbtfcgde7hvnovg47dou

Efficient evaluation for a subset of recursive queries

Gösta Grahne, Seppo Sippu, Eljas Soisalon-Soininen
1991 The Journal of Logic Programming  
An algorithm for recursive query evaluation is usually organized so that it carries along a vector of intermediate relations representing the current state of the evaluation.  ...  Indeed, a current trend in the development of query-processing strategies is to recognize commonly occuring subclasses of recursive queries that can be evaluated efficiently using algorithms specially  ...  In other words, the binary relation " ** " is the reflexive transitive closure of the binary relation " * ". Let p(C) be an instantiated literal.  ... 
doi:10.1016/0743-1066(91)90039-r fatcat:zjjbx6cbozgrlmiyopgdaxgqp4

Processing fuzzy spatial queries: a configuration similarity approach

1999 International Journal of Geographical Information Science  
Then we apply pre-processing techniques to explicate constraints in the query, and present algorithms that effectively solve the problem.  ...  Extensive experimental results demonstrate the applicability of our approach to images and queries of considerable size.  ...  We would like to thank Nikos Mamoulis, Dimitris Meretakis and Chung Po Loi for helping with the implementation.  ... 
doi:10.1080/136588199241373 fatcat:jxizbdnk55a33bo6uvtyio6loa

Image similarity retrieval by spatial constraints

Dimitris Papadias, Nikos Mamoulis, Dimitris Meretakis
1998 Proceedings of the seventh international conference on Information and knowledge management - CIKM '98  
This paper focuses on the development of effective methods that take advantage of the special structure of the spatial domain to achieve good average performance even for large images and queries.  ...  This query can be formulated as a constraint satisfaction problem (CSP) where the query variables are nodes of the corresponding constraint network and the image objects constitute the domain of each variable  ...  Preprocessing, which involves computing the transitive closure of the query and reordering of variables based on strictness of constraints, facilitates efficiency.  ... 
doi:10.1145/288627.288669 dblp:conf/cikm/PapadiasMM98 fatcat:nxsdseytmfchhfta2lir2pkuna

Extension table built-ins for prolog

Changguan Fan, Suzanne Wagner Dietrich
1992 Software, Practice & Experience  
This paper presents an efficient implementation of extension tables as a global data structure in Prolog, which includes a set of built-in primitives for manipulating the extension table.  ...  The ET* algorithm is a complete evaluation strategy for Datalog programs, which are logic programs without function symbols.  ...  Warren for his assistance on the implementation of nondeterministic 'built-ins'. We would like to extend our thanks to Frank W. Calliss and Saumya K.  ... 
doi:10.1002/spe.4380220706 fatcat:kwumtenmt5fwtbviuu7cztmzym

A Variant of Earley Deduction With Partial Evaluation [article]

Heike Stephan, Stefan Brass
2014 arXiv   pre-print
We present an algorithm for query evaluation given a logic program consisting of function-free Datalog rules.  ...  In certain cases, the new method is more efficient than SLDMagic and the standard Magic Set method since it can process several deduction steps as one.  ...  Conclusion We have presented an algorithm for efficient query evaluation and preprocessing of function-free logic programs based on Earley Deduction.  ... 
arXiv:1405.5645v1 fatcat:xgycljiak5cyvayjx5htamrgga

A Materialized View for the Same Generation Query in Deductive Databases

Nabil Arman
2012 Computer and Information Science  
Finally, simulations are used to compare the materialized view approach with other approaches that are used to compute the results of the same generation queries.  ...  The simplicity of implementation of linear recursive rules, like same generation rules, is far from the difficulty and the cost of computing the results of queries based on these recursive rules.  ...  In this paper, materialized views are used to speed up the performance of the same generation queries, which are more costly than transitive closure queries and occur frequently in deductive databases  ... 
doi:10.5539/cis.v5n6p1 fatcat:w4gf7kjwzzb4jmgdifcjur5gpe

Algebraic optimization of recursive queries

Maurice A.W. Houtsma, Peter M.G. Apers
1992 Data & Knowledge Engineering  
We also describe how to push selections into the resulting transitive closure operations.  ...  strategies for recursive queries.  ...  Acknowledgements We thank the reviewers for their comments, which have greatly improved the quality of the paper.  ... 
doi:10.1016/0169-023x(92)90029-b fatcat:tcydmhdf6zcgri3ty3dmhgmd5i

The Dichotomous Intensional Expressive Power of the Nested Relational Calculus with Powerset [chapter]

Limsoon Wong
2013 Lecture Notes in Computer Science  
In this paper, the efficiency of queries in N RC(powerset), a nested relational calculus with a powerset operation, is discussed.  ...  They do not tell us much about whether a query can be implemented efficiently in a query language. Yet, paradoxically, efficiency is of primary concern in computer science.  ...  space to implement the transitive closure query.  ... 
doi:10.1007/978-3-642-41660-6_30 fatcat:mcoyijtiajhurbb3qq3gd7ipme

Program termination analysis in polynomial time

Amir M. Ben-Amram, Chin Soon Lee
2007 ACM Transactions on Programming Languages and Systems  
While SCT is decidable, it has high worst-case complexity (complete for pspace). In this paper, we formulate an efficient approach to verify practical instances of SCT.  ...  Jones, we proposed the "size-change principle" for program termination: An infinite computation is impossible, if it would imply that some data decrease in size infinitely.  ...  This description is checked for non-termination using a procedure similar to the closure-based SCT algorithm. Generating size-change graphs from benchmark queries.  ... 
doi:10.1145/1180475.1180480 fatcat:r2jjr7eeonawlctveggou5ob5u

Program Termination Analysis in Polynomial Time [chapter]

Chin Soon Lee
2002 Lecture Notes in Computer Science  
While SCT is decidable, it has high worst-case complexity (complete for pspace). In this paper, we formulate an efficient approach to verify practical instances of SCT.  ...  Jones, we proposed the "size-change principle" for program termination: An infinite computation is impossible, if it would imply that some data decrease in size infinitely.  ...  This description is checked for non-termination using a procedure similar to the closure-based SCT algorithm. Generating size-change graphs from benchmark queries.  ... 
doi:10.1007/3-540-45821-2_14 fatcat:sfkbkzwtpfbz5gsf5ccvloyyg4

Efficient pattern matching over event streams

Jagrati Agrawal, Yanlei Diao, Daniel Gyllstrom, Neil Immerman
2008 Proceedings of the 2008 ACM SIGMOD international conference on Management of data - SIGMOD '08  
Furthermore, efficient evaluation of these pattern queries over streams requires new algorithms and optimizations: the conventional wisdom for stream query processing (i.e., using selection-join-aggregation  ...  We further analyze the runtime complexity of query evaluation using this model and develop a suite of techniques that improve runtime efficiency by exploiting sharing in storage and processing.  ...  It serves as an indicator of the amount of computation needed for a query. Any efficient algorithm should have a cost linear in it.  ... 
doi:10.1145/1376616.1376634 dblp:conf/sigmod/AgrawalDGI08 fatcat:doorsgy3rnaj3ekihwtq6uci6u
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