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Answering aggregation queries on hierarchical web sites using adaptive sampling

Foto N. Afrati, Paraskevas V. Lekeas, Chen Li
2005 Proceedings of the 14th ACM international conference on Information and knowledge management - CIKM '05  
Many Web sites publish their data in a hierarchical structure.  ...  In this paper we study how to answer such aggregation queries approximately with quality guarantees using sampling.  ...  In this study we make the following contributions. • We formulate a new problem about answering aggregation queries on hierarchical web sites.  ... 
doi:10.1145/1099554.1099605 dblp:conf/cikm/AfratiLL05 fatcat:adc2ob35e5hdthtr3lu3n72jue

Adaptive-sampling algorithms for answering aggregation queries on Web sites

Foto N. Afrati, Paraskevas V. Lekeas, Chen Li
2008 Data & Knowledge Engineering  
Many Web sites publish their data in a hierarchical structure.  ...  In this paper, we study how to answer such aggregation queries approximately with quality guarantees using sampling.  ...  In this study, we make the following contributions: • We formulate a new problem about answering aggregation queries on hierarchical Web sites.  ... 
doi:10.1016/j.datak.2007.09.014 fatcat:qzguvpwp2baovb3gonmajwvjgu

Distributed Data Streams [chapter]

Minos Garofalakis
2016 Encyclopedia of Database Systems  
In the one-shot model, a query is issued by a user at some site, and must be answered by "pulling" the  ...  ., over a communication network), support one-shot or continuous query answers, and be space, time, and communication efficient.  ...  consensus on the answer of a distributed stream query.  ... 
doi:10.1007/978-1-4899-7993-3_137-2 fatcat:fnr32foqjbb7hlhko5ob7532g4

Distributed Data Streams [chapter]

Tore Risch, Turkmen Canli, Ashfaq Khokhar, Jun Yang, Kamesh Munagala, Adam Silberstein, Panos K. Chrysanthis, Evaggelia Pitoura, Venkatesh Ganti, Amol Deshpande, Hong-Hai Do, James Caverlee (+156 others)
2009 Encyclopedia of Database Systems  
In the one-shot model, a query is issued by a user at some site, and must be answered by "pulling" the  ...  ., over a communication network), support one-shot or continuous query answers, and be space, time, and communication efficient.  ...  consensus on the answer of a distributed stream query.  ... 
doi:10.1007/978-0-387-39940-9_137 fatcat:d3hmw63lmzb4foz6yqwpbffqr4

Exploration and mining of web repositories

Nan Zhang, Gautam Das
2014 Proceedings of the 7th ACM international conference on Web search and data mining - WSDM '14  
Data Analytics o Directly support online analytics over the repository o Key Task: efficiently answer aggregate queries (COUNT, SUM, MIN, MAX, etc.) o Overlap with sampling, but a key difference on the  ...  Leser, "A Hierarchical Approach to Model Web Query Interfaces for Web Source Integration", VLDB, 2009.  ...  • Level 1: a query is needed to determine whether user A befriends B. • Level 2: a query reveals the list of user A's friends. • Level 3: a query reveals the list of user A's friends, as well as the degree  ... 
doi:10.1145/2556195.2556197 dblp:conf/wsdm/0004D14 fatcat:qd3n4ceurrhbxpyw5ix3vcoe3q

Cooperative Caching for Grid Based DataWarehouses

Frank Dehne, Michael Lawrence, Dalhousie University
2007 Seventh IEEE International Symposium on Cluster Computing and the Grid (CCGrid '07)  
Our application follows a two-tiered process for answering queries based on sharing cached OLAP data between the users at the local grid site, and using grid scheduling approaches to execute the remaining  ...  A new technique for extraction and aggregation of shared cached OLAP data is proposed, along with an efficient, aggregateaware cache controller.  ...  The first tier involves using the Distributed Cache Index Service on the local Site Broker to find all of the locally cached fragments which can be used to answer parts of the query.  ... 
doi:10.1109/ccgrid.2007.34 dblp:conf/ccgrid/DehneL07 fatcat:zg3rcjilh5dtbcg35uck3juij4

Personalizing Interactions with Information Systems [chapter]

Saverio Perugini, Naren Ramakrishnan
2003 Advances in Computers  
The survey covers mechanisms for information-finding on the web, advanced information retrieval systems, dialogbased applications, and mobile access paradigms.  ...  Specific emphasis is placed on studying how users interact with an information system and how the system can encourage and foster interaction.  ...  ., web sites) with adaptations of traditional SELECT-FROM-WHERE queries.  ... 
doi:10.1016/s0065-2458(03)57007-3 fatcat:rdooy2c4gnfajgvu246kjzm2ja

Cooperative caching for grid-enabled OLAP

F. Dehne, M. Lawrence, A. Rau Chaplin
2009 International Journal of Grid and Utility Computing  
Our application follows a two-tiered process for answering queries based on sharing Cached OLAP data between the users at the local grid site and using grid scheduling approaches to execute the remaining  ...  In this paper, we propose a grid-based On-Line Analytical Processing (OLAP) application which distributes query computation across an enterprise grid.  ...  The Query Service uses the Distributed Cache Index Service: a global index implemented on the Site Broker of all Cached fragments on the local site.  ... 
doi:10.1504/ijguc.2009.022032 fatcat:goshhjjx2vh65jbdgfd3cyrz7u

HerbariaViz: A web-based client–server interface for mapping and exploring flora observation data

Tom Auer, Alan M. MacEachren, Craig McCabe, Scott Pezanowski, Michael Stryker
2011 Ecological Informatics  
With a focus on cartographically-sound visualization and user-friendly interaction, we introduce HerbariaViz, a web mapping application that provides space-time-species data query responses efficiently  ...  In this paper, we report on development and implementation of a web-based client-server map interface to facilitate open mapping and exploration of the dataset.  ...  Acknowledgements We extend our appreciation to Dick Moe at the Jepson Herbarium, UC Berkeley for making the data used here available to us and for his insightful comments about the system on an early draft  ... 
doi:10.1016/j.ecoinf.2010.09.001 fatcat:u66jicv3pre4tibqxvxr7nfqse

Semantic and distributed entity search in the web of data

Robert Neumayer
2012 SIGIR Forum  
, c) how can these elements be used in a theoretically sound and effective way?, and d) How can the techniques be adapted to a distributed environment?  ...  The main contributions are as follows: • We develop a hybrid approach to search in the Web of Data, using elements from traditional information retrieval and structured retrieval alike. • We formalise  ...  However, current state-of-the-art web search engines crawl the We also performed an experiment with a large network of N P =1,000 peers to study the scalability of hybrid aggregation.  ... 
doi:10.1145/2492189.2492203 fatcat:vnqc7pfhpffhnmt7xngort6v5u

Distributed top-k aggregation queries at large

Thomas Neumann, Matthias Bender, Sebastian Michel, Ralf Schenkel, Peter Triantafillou, Gerhard Weikum
2009 Distributed and parallel databases  
input sources, and 3) data-adaptive sampling of a small subset of input sources in scenarios with hundreds or thousands of query-relevant network nodes.  ...  The optimizations address three degrees of freedom: 1) hierarchically grouping input lists into top-k operator trees and optimizing the tree structure, 2) computing data-adaptive scan depths for different  ...  TreeTPUT uses hierarchical query execution plans resulting from the optimizations introduced in Sect. 5, in addition to the adaptive-threshold technique of Adap-tiveTPUT.  ... 
doi:10.1007/s10619-009-7041-z fatcat:qid6zibirvfm5c4i3xfkz2a4z4

HiPPIS

Katerina Doka, Dimitrios Tsoumakos, Nectarios Koziris
2008 Proceeding of the 10th ACM workshop on Web information and data management - WIDM '08  
Extensive experimental evaluations show that, on top of the advantages that a distributed storage offers, our method answers the large majority of incoming queries, both point and aggregate ones, without  ...  Our scheme utilizes an adaptive algorithm that automatically adjusts the level of indexing according to the granularity of the incoming queries, without assuming any prior knowledge of the workload.  ...  querying hierarchical data.  ... 
doi:10.1145/1458502.1458513 dblp:conf/widm/DokaTK08 fatcat:yntjzpz7jjfmvp3uvpkuj4gltm

Models and issues in data stream systems

Brian Babcock, Shivnath Babu, Mayur Datar, Rajeev Motwani, Jennifer Widom
2002 Proceedings of the twenty-first ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems - PODS '02  
, while traditional DBMS's focus largely on the opposite goal of precise answers computed by stable query plans.  ...  ., network measurements, call records, web page visits, sensor readings, and so on.  ...  The Traderbot web site [83] gives some examples of one-time and continuous queries that are commonly posed by its customers.  ... 
doi:10.1145/543613.543615 dblp:conf/pods/BabcockBDMW02 fatcat:avqbzp74v5buvkzqoayslqwr64

IrisNet: An architecture for a worldwide sensor web

P.B. Gibbons, B. Karp, Yan Ke, S. Nath, S. Seshan
2003 IEEE pervasive computing  
They use simple sensors that provide time series of single numerical measurements, such as temperature, pressure, light level, and so on.  ...  A particular sensor might be positioned to measure a physical area of interest for one particular service, but it might, in fact, provide data useful in multiple services.  ...  Finally, we thank Mark Abbott, Rob Holman, Chuck Sears, Ganesh Gopalan, and Curt Vandetta for their collaboration on the coastal-imaging service.  ... 
doi:10.1109/mprv.2003.1251166 fatcat:iusayvuahbenhm5jln6zlsfykq

When one sample is not enough

Panagiotis G. Ipeirotis, Luis Gravano
2004 Proceedings of the 2004 ACM SIGMOD international conference on Management of data - SIGMOD '04  
Specifically, we exploit a (given or derived) hierarchical categorization of the databases and adapt the notion of "shrinkage" -a form of smoothing that has been used successfully for document classification-to  ...  Previous research has developed algorithms for constructing an approximate content summary of a text database from a small document sample extracted via querying.  ...  Web: This set contains the top-5 real web databases from each of the 54 leaf categories of the hierarchy, as ranked in the Google Directory 6 , plus other arbitrarily selected web sites, for a total of  ... 
doi:10.1145/1007568.1007655 dblp:conf/sigmod/IpeirotisG04 fatcat:uobh26usj5eldcpo6ab5bagx3a
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