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Practical selectivity estimation through adaptive sampling

Richard J. Lipton, Jeffrey F. Naughton, Donovan A. Schneider
1990 SIGMOD record  
Recently we have proposed an adaptive, random sampling algorithm for general query size estlmatlon In earlier work we analyzed the asymptotic ef'l?  ...  are not made or dwtnbuted for dwect commerwdl advantage, the ACM copy@ noWe and the title of the pubbcatlon and ID date appear, and nouce II pm that cqyng II by pmmwon of the Assoaat!  ...  construct the answer to the query The sampling algorithm works by repeatedly randomly choosmg one of these subsets, computmg the size of the subset, then estimating the size of the query result based  ... 
doi:10.1145/93605.93611 fatcat:sjbp5i5iynglvp2b356a3rz4qy

The Power of an Example: Hidden Set Size Approximation Using Group Queries and Conditional Sampling [article]

Dana Ron, Gilad Tsur
2014 arXiv   pre-print
We study the difference between these two versions under different conditions on the subsets that the algorithm may query/sample, and in both the case that the algorithm is adaptive and the case where  ...  it is non-adaptive.  ...  We are interested in the number of queries/samples used by the algorithm as a function of the size of the universe U , which we denote by n, the the size of set S, which we denote by w, and the approximation  ... 
arXiv:1404.5568v1 fatcat:barptd2ztne6dlafsyhgb7vc2q

Adaptive-sampling algorithms for answering aggregation queries on Web sites

Foto N. Afrati, Paraskevas V. Lekeas, Chen Li
2008 Data & Knowledge Engineering  
We study how to use adaptive-sampling techniques that allocate the resources adaptively based on partial samples retrieved from different nodes in the hierarchy.  ...  In this paper, we study how to answer such aggregation queries approximately with quality guarantees using sampling.  ...  Table 5 shows the estimations of adaptive and naive algorithms as a function of allocated resources with respect to the total sample size.  ... 
doi:10.1016/j.datak.2007.09.014 fatcat:qzguvpwp2baovb3gonmajwvjgu

Distributed query sampling

James Caverlee, Ling Liu, Joonsoo Bae
2006 Proceedings of the 29th annual international ACM SIGIR conference on Research and development in information retrieval - SIGIR '06  
In the second phase the sampling process is dynamically scheduled based on estimated database size and quality parameters derived during the previous sampling process.  ...  We present an adaptive distributed query-sampling framework that is quality-conscious for extracting high-quality text database samples.  ...  smaller seed samples for estimating the database size.  ... 
doi:10.1145/1148170.1148230 dblp:conf/sigir/CaverleeLB06 fatcat:au6kuecatrarfbqpjzmentoywy

Adaptive statistics in Oracle 12c

Sunil Chakkappen, Suratna Budalakoti, Ramarajan Krishnamachari, Satyanarayana R Valluri, Alan Wood, Mohamed Zait
2017 Proceedings of the VLDB Endowment  
We limit the overhead of the additional work by confining their use to cases where it matters the most, caching the computed statistics, and using table samples.  ...  The final execution plan produced by the query optimizer depends on the quality of information used by the cost model, as well as the sophistication of the cost model.  ...  We describe two of these, adaptive sampling, and SQL plan directives (SPDs), below. Adaptive Sampling: Use sample of the table in statistics queries to estimate the cardinality.  ... 
doi:10.14778/3137765.3137785 fatcat:rgypno2ahfhj5p73xnnbpmo334

Adaptive query-based sampling for distributed IR

Leif Azzopardi, Mark Baillie, Fabio Crestani
2006 Proceedings of the 29th annual international ACM SIGIR conference on Research and development in information retrieval - SIGIR '06  
Azzopardi, L. and Baillie, M. and Crestani, F. (2006) Adaptive query-based sampling for distributed IR.  ...  EVALUATION The aim of this experiment is to compare the performance of the estimates obtained by adaptive method (QBS-PL) versus threshold method (QBS-T) across resource selection accuracy, sampling efficiency  ... 
doi:10.1145/1148170.1148277 dblp:conf/sigir/AzzopardiBC06 fatcat:itk6bimedzdc5jixd3hbu6prhi

Mobile Join Operators for Restricted Sources

Belgin Ozakar, Franck Morvan, Abdelkader Hameurlain
2005 Mobile Information Systems  
The difference between the two new query operators lies in their level of adaptation ability to the execution environment.  ...  Mobile operators of restricted sources are capable to deal with restricted sources and react to the variations between the compile-time estimations and run-time computations of data during query execution  ...  We by develop efficient query execution operators which are capable to work with restricted sources and which are, at the same time, adaptive to the run time parameters of data (i.e. size, cost of sending  ... 
doi:10.1155/2005/705348 fatcat:w6ssxf3lmvgsxkkftd7jqjhiva

Adaptive estimation in weighted group testing

Jayadev Acharya, Clement L. Canonne, Gautam Kamath
2015 2015 IEEE International Symposium on Information Theory (ISIT)  
We consider a generalization of the problem of estimating the support size of a hidden subset S of a universe U from samples.  ...  This framework falls under the group testing [1] and the conditional sampling models [2, 3]. In group testing, for a query set, we are told if it intersects with the set S.  ...  Adaptive lower bound It is also possible to adapt the algorithms to obtain bounds on the number of adaptive queries to estimate W . The construction is the same as for the non-adaptive setting.  ... 
doi:10.1109/isit.2015.7282829 dblp:conf/isit/AcharyaCK15 fatcat:zjk37l35tvdrji4juo5l3sos3y

Correcting execution of distributed queries

P. Bodorik, J. Pyra, J. S. Riordon
1990 Proceedings of the second international symposium on Databases in parallel and distributed systems - DPDS '90  
Algorithms for processing distributed queries require & estimates of the size of intermediate relations.  ...  Adaptive query execution may be used to alleviate the problem.  ...  It is used to quickly estimate the delay of the alternative strategy when the size of the result is estimated using sampling.  ... 
doi:10.1145/319057.319098 fatcat:aofmn4mxenbp5aifejaglehewq

Bifocal sampling for skew-resistant join size estimation

Sumit Ganguly, Phillip B. Gibbons, Yossi Matias, Avi Silberschatz
1996 SIGMOD record  
This paper introduces bifocal sampling, a new technique for estimating the size of an equi-join of two relations.  ...  Introduction Accurate and inexpensive estimation of database query sizes is useful for many purposes. Such estimates are used by query optimizers, to compare costs of alternate join plans.  ...  Finally, the estimate of query sizes is of interest by itself in some applications, such as nancial audits and statistical studies.  ... 
doi:10.1145/235968.233340 fatcat:ccd6jltldbhm5ong4uq2z4z6om

Bifocal sampling for skew-resistant join size estimation

Sumit Ganguly, Phillip B. Gibbons, Yossi Matias, Avi Silberschatz
1996 Proceedings of the 1996 ACM SIGMOD international conference on Management of data - SIGMOD '96  
This paper introduces bifocal sampling, a new technique for estimating the size of an equi-join of two relations.  ...  Introduction Accurate and inexpensive estimation of database query sizes is useful for many purposes. Such estimates are used by query optimizers, to compare costs of alternate join plans.  ...  Finally, the estimate of query sizes is of interest by itself in some applications, such as nancial audits and statistical studies.  ... 
doi:10.1145/233269.233340 dblp:conf/sigmod/GangulyGMS96 fatcat:o6g6d3kvcjblzfru2ibc5nap3m

LiquidXML: Adaptive XML Content Redistribution [article]

Jesús Camacho-Rodríguez, Asterios Katsifodimos, Ioana Manolescu (INRIA Saclay - Ile de France, LRI), Alexandra Roatis (INRIA Saclay - Ile de France, UVT)
2010 arXiv   pre-print
The "liquid" aspect of XML management is twofold: XML data flows from many sources towards many consumers, and its distribution in the network continuously adapts to improve query performance.  ...  The novelty of LiquidXML relies in its adaptive method of choosing which data fragments are stored where, to improve performance.  ...  Acknowledgements This work has been partially funded by Agence Nationale de la Recherche, decision ANR-08-DEFIS-004. We are grateful to S. Zoupanos, A. Tilea and V.  ... 
arXiv:1008.0557v2 fatcat:etjml4ax7rctpf3igfssx5goey

Non-Adaptive Edge Counting and Sampling via Bipartite Independent Set Queries [article]

Raghavendra Addanki, Andrew McGregor, Cameron Musco
2022 arXiv   pre-print
Building on our edge estimation result, we give the first non-adaptive algorithm for outputting a nearly uniformly sampled edge with query complexity Õ(ϵ^-6log^6 n), improving on the works of Dell et al  ...  We study the problem of estimating the number of edges in an n-vertex graph, accessed via the Bipartite Independent Set query model introduced by Beame et al. (ITCS '18).  ...  This work was supported by a Dissertation Writing Fellowship awarded by the Manning College of Information and Computer Sciences, University of Massachusetts Amherst to R. Addanki.  ... 
arXiv:2207.02817v1 fatcat:dmzy3x6xwba5xpqvmlsq4homfu

Efficient sampling strategies for relational database operations

Richard J. Lipton, Jeffrey F. Naughton, Donovan A. Schneider, S. Seshadri
1993 Theoretical Computer Science  
Recently, we have proposed an adaptive, random-sampling algorithm for general query size estimation in databases.  ...  Also, we provide "sanity bounds" to deal with queries for which the underlying data are extremely skewed or the query result is very small.  ...  Recently, we proposed the first adaptive random-sampling algorithm for general query size estimation 119, 20) .  ... 
doi:10.1016/0304-3975(93)90224-h fatcat:i5oo3ayranc7rorxjemspc4p5y

LiquidXML

Jesús Camacho-Rodríguez, Asterios Katsifodimos, Ioana Manolescu, Alexandra Roatis
2010 Proceedings of the 19th ACM international conference on Information and knowledge management - CIKM '10  
The challenge then is to efficiently (re-)distribute the published content in the network, possibly in overlapping, redundant fragments, to support efficient processing of queries at each peer.  ...  Acknowledgements This work has been partially funded by Agence Nationale de la Recherche, decision ANR-08-DEFIS-004. We are grateful to S. Zoupanos, A. Tilea and V.  ...  View size estimation For each document published by peer p, a compact document synopsis is also indexed in the DHT.  ... 
doi:10.1145/1871437.1871776 dblp:conf/cikm/Camacho-RodriguezKMR10 fatcat:ysvji6fhn5f2rpkxgyk6wngmnm
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