Query Processing over Uncertain Databases

Query Processing over Uncertain Databases PDF Author: Lei Chen
Publisher: Springer Nature
ISBN: 3031018966
Category : Computers
Languages : en
Pages : 91

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Book Description
Due to measurement errors, transmission lost, or injected noise for privacy protection, uncertainty exists in the data of many real applications. However, query processing techniques for deterministic data cannot be directly applied to uncertain data because they do not have mechanisms to handle data uncertainty. Therefore, efficient and effective manipulation of uncertain data is a practical yet challenging research topic. In this book, we start from the data models for imprecise and uncertain data, move on to defining different semantics for queries on uncertain data, and finally discuss the advanced query processing techniques for various probabilistic queries in uncertain databases. The book serves as a comprehensive guideline for query processing over uncertain databases. Table of Contents: Introduction / Uncertain Data Models / Spatial Query Semantics over Uncertain Data Models / Spatial Query Processing over Uncertain Databases / Conclusion

Query Processing over Uncertain Databases

Query Processing over Uncertain Databases PDF Author: Lei Chen
Publisher: Springer Nature
ISBN: 3031018966
Category : Computers
Languages : en
Pages : 91

Get Book

Book Description
Due to measurement errors, transmission lost, or injected noise for privacy protection, uncertainty exists in the data of many real applications. However, query processing techniques for deterministic data cannot be directly applied to uncertain data because they do not have mechanisms to handle data uncertainty. Therefore, efficient and effective manipulation of uncertain data is a practical yet challenging research topic. In this book, we start from the data models for imprecise and uncertain data, move on to defining different semantics for queries on uncertain data, and finally discuss the advanced query processing techniques for various probabilistic queries in uncertain databases. The book serves as a comprehensive guideline for query processing over uncertain databases. Table of Contents: Introduction / Uncertain Data Models / Spatial Query Semantics over Uncertain Data Models / Spatial Query Processing over Uncertain Databases / Conclusion

Query Processing over Incomplete Databases

Query Processing over Incomplete Databases PDF Author: Yunjun Gao
Publisher: Springer Nature
ISBN: 303101863X
Category : Computers
Languages : en
Pages : 106

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Book Description
Incomplete data is part of life and almost all areas of scientific studies. Users tend to skip certain fields when they fill out online forms; participants choose to ignore sensitive questions on surveys; sensors fail, resulting in the loss of certain readings; publicly viewable satellite map services have missing data in many mobile applications; and in privacy-preserving applications, the data is incomplete deliberately in order to preserve the sensitivity of some attribute values. Query processing is a fundamental problem in computer science, and is useful in a variety of applications. In this book, we mostly focus on the query processing over incomplete databases, which involves finding a set of qualified objects from a specified incomplete dataset in order to support a wide spectrum of real-life applications. We first elaborate the three general kinds of methods of handling incomplete data, including (i) discarding the data with missing values, (ii) imputation for the missing values, and (iii) just depending on the observed data values. For the third method type, we introduce the semantics of k-nearest neighbor (kNN) search, skyline query, and top-k dominating query on incomplete data, respectively. In terms of the three representative queries over incomplete data, we investigate some advanced techniques to process incomplete data queries, including indexing, pruning as well as crowdsourcing techniques.

Query Processing Over Incomplete Databases

Query Processing Over Incomplete Databases PDF Author: Yunjun Gao
Publisher: Morgan & Claypool
ISBN: 9781681734224
Category : Computers
Languages : en
Pages : 122

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Book Description
Incomplete data is part of life and almost all areas of scientific studies. Users tend to skip certain fields when they fill out online forms; participants choose to ignore sensitive questions on surveys; sensors fail, resulting in the loss of certain readings; publicly viewable satellite map services have missing data in many mobile applications; and in privacy-preserving applications, the data is incomplete deliberately in order to preserve the sensitivity of some attribute values. Query processing is a fundamental problem in computer science, and is useful in a variety of applications. In this book, we mostly focus on the query processing over incomplete databases, which involves finding a set of qualified objects from a specified incomplete dataset in order to support a wide spectrum of real-life applications. We first elaborate the three general kinds of methods of handling incomplete data, including (i) discarding the data with missing values, (ii) imputation for the missing values, and (iii) just depending on the observed data values. For the third method type, we introduce the semantics of k-nearest neighbor (kNN) search, skyline query, and top-k dominating query on incomplete data, respectively. In terms of the three representative queries over incomplete data, we investigate some advanced techniques to process incomplete data queries, including indexing, pruning as well as crowdsourcing techniques.

Query Processing in Database Systems

Query Processing in Database Systems PDF Author: W. Kim
Publisher: Springer Science & Business Media
ISBN: 3642823750
Category : Computers
Languages : en
Pages : 367

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Book Description
This book is an anthology of the results of research and development in database query processing during the past decade. The relational model of data provided tremendous impetus for research into query processing. Since a relational query does not specify access paths to the stored data, the database management system (DBMS) must provide an intelligent query-processing subsystem which will evaluate a number of potentially efficient strategies for processing the query and select the one that optimizes a given performance measure. The degree of sophistication of this subsystem, often called the optimizer, critically affects the performance of the DBMS. Research into query processing thus started has taken off in several directions during the past decade. The emergence of research into distributed databases has enormously complicated the tasks of the optimizer. In a distributed environment, the database may be partitioned into horizontal or vertical fragments of relations. Replicas of the fragments may be stored in different sites of a network and even migrate to other sites. The measure of performance of a query in a distributed system must include the communication cost between sites. To minimize communication costs for-queries involving multiple relations across multiple sites, optimizers may also have to consider semi-join techniques.

Probabilistic Databases

Probabilistic Databases PDF Author: Dan Suciu
Publisher: Morgan & Claypool Publishers
ISBN: 1608456803
Category : Computers
Languages : en
Pages : 183

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Book Description
Probabilistic databases are databases where the value of some attributes or the presence of some records are uncertain and known only with some probability. Applications in many areas such as information extraction, RFID and scientific data management, data cleaning, data integration, and financial risk assessment produce large volumes of uncertain data, which are best modeled and processed by a probabilistic database. This book presents the state of the art in representation formalisms and query processing techniques for probabilistic data. It starts by discussing the basic principles for representing large probabilistic databases, by decomposing them into tuple-independent tables, block-independent-disjoint tables, or U-databases. Then it discusses two classes of techniques for query evaluation on probabilistic databases. In extensional query evaluation, the entire probabilistic inference can be pushed into the database engine and, therefore, processed as effectively as the evaluation of standard SQL queries. The relational queries that can be evaluated this way are called safe queries. In intensional query evaluation, the probabilistic inference is performed over a propositional formula called lineage expression: every relational query can be evaluated this way, but the data complexity dramatically depends on the query being evaluated, and can be #P-hard. The book also discusses some advanced topics in probabilistic data management such as top-k query processing, sequential probabilistic databases, indexing and materialized views, and Monte Carlo databases. Table of Contents: Overview / Data and Query Model / The Query Evaluation Problem / Extensional Query Evaluation / Intensional Query Evaluation / Advanced Techniques

Web Technologies and Applications

Web Technologies and Applications PDF Author: Xiaoyong Du
Publisher: Springer Science & Business Media
ISBN: 364220290X
Category : Computers
Languages : en
Pages : 503

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Book Description
This book constitutes the proceedings of the 13th Asia-Pacific Conference APWeb 2011 held in conjunction with the APWeb 2011 Workshops XMLDM and USD, in Beijing, China, in April 2011. The 26 full papers presented together with 10 short papers, 3 keynote talks, and 4 demo papers were carefully reviewed and selected from 104 submissions. The submissions range over a variety of topics such as classification and clustering; spatial and temporal databases; personalization and recommendation; data analysis and application; Web mining; Web search and information retrieval; complex and social networks; and secure and semantic Web.

Database Systems for Advanced Applications

Database Systems for Advanced Applications PDF Author: Sang-goo Lee
Publisher: Springer Science & Business Media
ISBN: 3642290345
Category : Computers
Languages : en
Pages : 355

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Book Description
This two volume set LNCS 7238 and LNCS 7239 constitutes the refereed proceedings of the 17th International Conference on Database Systems for Advanced Applications, DASFAA 2012, held in Busan, South Korea, in April 2012. The 44 revised full papers and 8 short papers presented together with 2 invited keynote papers, 8 industrial papers, 8 demo presentations, 4 tutorials and 1 panel paper were carefully reviewed and selected from a total of 159 submissions. The topics covered are query processing and optimization, data semantics, XML and semi-structured data, data mining and knowledge discovery, privacy and anonymity, data management in the Web, graphs and data mining applications, temporal and spatial data, top-k and skyline query processing, information retrieval and recommendation, indexing and search systems, cloud computing and scalability, memory-based query processing, semantic and decision support systems, social data, data mining.

Database Systems for Advanced Applications

Database Systems for Advanced Applications PDF Author: Xiaofang Zhou
Publisher: Springer
ISBN: 3642008879
Category : Computers
Languages : en
Pages : 815

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Book Description
This book constitutes the refereed proceedings of the 14th International Conference on Database Systems for Advanced Applications, DASFAA 2009, held in Brisbane, Australia, in April 2009. The 39 revised full papers and 22 revised short papers presented together with 3 invited keynote papers, 9 demonstration papers, 3 tutorial abstracts, and one panel abstract were carefully reviewed and selected from 186 submissions. The papers are organized in topical sections on uncertain data and ranking, sensor networks, graphs, RFID and data streams, skyline and rising stars, parallel and distributed processing, mining and analysis, XML query, privacy, XML keyword search and ranking, Web and Web services, XML data processing, and multimedia.

Database Systems for Advanced Applications

Database Systems for Advanced Applications PDF Author: Lei Chen
Publisher: Springer Science & Business Media
ISBN: 364204204X
Category : Computers
Languages : en
Pages : 383

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Book Description
This book constitutes the workshop proceedings of the 14th International Conference on Database Systems for Advanced Applications, DASFAA 2009, held in Brisbane, Australia, in April 2009. The volume contains six workshops, each focusing on specific research issues that contribute to the main themes of the DASFAA conference: The First International Workshop on Benchmarking of XML and Semantic Web Applications (BenchmarkX'09); The Second International Workshop on Managing Data Quality in Collaborative Information Systems (MCIS'09); The 1st International Workshop on Data and Process Provenance (WDPP'09); The First International Workshop on Privacy-Preserving Data Analysis (PPDA'09); The First International Workshop on Mobile Business Collaboration (MBC'09); and the First Ph.D. Workshop.

Transactions on Large-Scale Data- and Knowledge-Centered Systems XLIII

Transactions on Large-Scale Data- and Knowledge-Centered Systems XLIII PDF Author: Abdelkader Hameurlain
Publisher: Springer Nature
ISBN: 3662621991
Category : Computers
Languages : en
Pages : 139

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Book Description
The LNCS journal Transactions on Large-Scale Data- and Knowledge-Centered Systems focuses on data management, knowledge discovery, and knowledge processing, which are core and hot topics in computer science. Since the 1990s, the Internet has become the main driving force behind application development in all domains. An increase in the demand for resource sharing (e.g., computing resources, services, metadata, data sources) across different sites connected through networks has led to an evolution of data- and knowledge-management systems from centralized systems to decentralized systems enabling large-scale distributed applications providing high scalability. This, the 43rd issue of Transactions on Large-Scale Data- and Knowledge-Centered Systems, contains five revised selected regular papers. Topics covered include classification tasks, machine learning algorithms, top-k queries, business process redesign and a knowledge capitalization framework.