Proceedings. 20th International Conference on Data Engineering最新文献_第10页

GODIVA: lightweight data management for scientific visualization applications GODIVA:用于科学可视化应用程序的轻量级数据管理

Proceedings. 20th International Conference on Data Engineering Pub Date : 2004-03-30 DOI: 10.1109/ICDE.2004.1320041

Xiaosong Ma, M. Winslett, Johnny Norris, X. Jiao, R. Fiedler

引用次数: 17

An efficient framework for order optimization 一个高效的订单优化框架

Proceedings. 20th International Conference on Data Engineering Pub Date : 2004-03-30 DOI: 10.1109/ICDE.2004.1320019

Thomas Neumann, G. Moerkotte

{"title":"An efficient framework for order optimization","authors":"Thomas Neumann, G. Moerkotte","doi":"10.1109/ICDE.2004.1320019","DOIUrl":"https://doi.org/10.1109/ICDE.2004.1320019","url":null,"abstract":"Since the introduction of cost-based query optimization, the performance-critical role of interesting orders has been recognized. Some algebraic operators change interesting orders (e.g. sort and select), while others exploit interesting orders (e.g. merge join). The two operations performed by any query optimizer during plan generation are 1) computing the resulting order given an input order and an algebraic operator and 2) determining the compatibility between a given input order and the required order a given algebraic operator can beneficially exploit. Since these two operations are called millions of times during plan generation, they are highly performance-critical. The third crucial parameter is the space requirement for annotating every plan node with its output order. Lately, a powerful framework for reasoning about orders has been developed, which is based on functional dependencies. Within this framework, the current state-of-the-art algorithms for implementing the above operations both have a lower bound time requirement /spl Omega/(n), where n is the number of functional dependencies involved. Further, the lower bound for the space requirement for every plan node is /spl Omega/(n). We improve these bounds by new algorithms with upper time bounds O(1). That is, our algorithms for both operations work in constant time during plan generation, after a one-time preparation step. Further, the upper bound for the space requirement for plan nodes is O(1) for our approach. Besides, our algorithm reduces the search space by detecting and ignoring irrelevant orderings. Experimental results with a full-fledged query optimizer show that our approach significantly reduces the total time needed for plan generation. As a corollary of our experiments, it follows that the time spent for order processing is a nonnegligible part of plan generation.","PeriodicalId":358862,"journal":{"name":"Proceedings. 20th International Conference on Data Engineering","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132755655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 31

Engineering a fast online persistent suffix tree construction 工程一个快速的在线持久后缀树构建

Proceedings. 20th International Conference on Data Engineering Pub Date : 2004-03-30 DOI: 10.1109/ICDE.2004.1320040

Srikanta J. Bedathur, J. Haritsa

引用次数: 58

Selectivity estimation for XML twigs XML分支的选择性估计

Proceedings. 20th International Conference on Data Engineering Pub Date : 2004-03-30 DOI: 10.1109/ICDE.2004.1320003

N. Polyzotis, M. Garofalakis, Y. Ioannidis

{"title":"Selectivity estimation for XML twigs","authors":"N. Polyzotis, M. Garofalakis, Y. Ioannidis","doi":"10.1109/ICDE.2004.1320003","DOIUrl":"https://doi.org/10.1109/ICDE.2004.1320003","url":null,"abstract":"Twig queries represent the building blocks of declarative query languages over XML data. A twig query describes a complex traversal of the document graph and generates a set of element tuples based on the intertwined evaluation (i.e., join) of multiple path expressions. Estimating the result cardinality of twig queries or, equivalently, the number of tuples in such a structural (path-based) join, is a fundamental problem that arises in the optimization of declarative queries over XML. It is crucial, therefore, to develop concise synopsis structures that summarize the document graph and enable such selectivity estimates within the time and space constraints of the optimizer. We propose novel summarization and estimation techniques for estimating the selectivity of twig queries with complex XPath expressions over tree-structured data. Our approach is based on the XSKETCH model, augmented with new types of distribution information for capturing complex correlation patterns across structural joins. Briefly, the key idea is to represent joins as points in a multidimensional space of path counts that capture aggregate information on the contents of the resulting element tuples. We develop a systematic framework that combines distribution information with appropriate statistical assumptions in order to provide selectivity estimates for twig queries over concise XSKETCH synopses and we describe an efficient algorithm for constructing an accurate summary for a given space budget. Implementation results with both synthetic and real-life data sets verify the effectiveness of our approach and demonstrate its benefits over earlier techniques.","PeriodicalId":358862,"journal":{"name":"Proceedings. 20th International Conference on Data Engineering","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128292242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 72

A peer-to-peer framework for caching range queries 用于缓存范围查询的对等框架

Proceedings. 20th International Conference on Data Engineering Pub Date : 2004-03-30 DOI: 10.1109/ICDE.2004.1319993

O. Sahin, Abhishek K. Gupta, D. Agrawal, A. E. Abbadi

引用次数: 147

Online amnesic approximation of streaming time series 流时间序列的在线遗忘近似

Proceedings. 20th International Conference on Data Engineering Pub Date : 2004-03-30 DOI: 10.1109/ICDE.2004.1320009

Themis Palpanas, M. Vlachos, Eamonn J. Keogh, D. Gunopulos, Wagner Truppel

{"title":"Online amnesic approximation of streaming time series","authors":"Themis Palpanas, M. Vlachos, Eamonn J. Keogh, D. Gunopulos, Wagner Truppel","doi":"10.1109/ICDE.2004.1320009","DOIUrl":"https://doi.org/10.1109/ICDE.2004.1320009","url":null,"abstract":"The past decade has seen a wealth of research on time series representations, because the manipulation, storage, and indexing of large volumes of raw time series data is impractical. The vast majority of research has concentrated on representations that are calculated in batch mode and represent each value with approximately equal fidelity. However, the increasing deployment of mobile devices and real time sensors has brought home the need for representations that can be incrementally updated, and can approximate the data with fidelity proportional to its age. The latter property allows us to answer queries about the recent past with greater precision, since in many domains recent information is more useful than older information. We call such representations amnesic. While there has been previous work on amnesic representations, the class of amnesic functions possible was dictated by the representation itself. We introduce a novel representation of time series that can represent arbitrary, user-specified amnesic functions. For example, a meteorologist may decide that data that is twice as old can tolerate twice as much error, and thus, specify a linear amnesic function. In contrast, an econometrist might opt for an exponential amnesic function. We propose online algorithms for our representation, and discuss their properties. Finally, we perform an extensive empirical evaluation on 40 datasets, and show that our approach can efficiently maintain a high quality amnesic approximation.","PeriodicalId":358862,"journal":{"name":"Proceedings. 20th International Conference on Data Engineering","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2004-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130782603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 161

XJoin index: indexing XML data for efficient handling of branching path expressions XJoin索引:为XML数据建立索引，以便有效地处理分支路径表达式

Proceedings. 20th International Conference on Data Engineering Pub Date : 2004-03-30 DOI: 10.1109/ICDE.2004.1320059

E. Bertino, B. Catania, Wen Qiang Wang

引用次数: 11

Integrating XML data in the TARGIT OLAP system 在TARGIT OLAP系统中集成XML数据

Proceedings. 20th International Conference on Data Engineering Pub Date : 2004-03-30 DOI: 10.1504/IJWET.2008.019945

T. Pedersen, Dennis Pedersen, Jesper Pedersen

引用次数: 42

Hiding data accesses in steganographic file system 在隐写文件系统中隐藏数据访问

Proceedings. 20th International Conference on Data Engineering Pub Date : 2004-03-30 DOI: 10.1109/ICDE.2004.1320028

Xuan Zhou, HweeHwa Pang, K. Tan

引用次数: 36

Authenticating query results in edge computing 验证边缘计算查询结果

Proceedings. 20th International Conference on Data Engineering Pub Date : 2004-03-30 DOI: 10.1109/ICDE.2004.1320027

HweeHwa Pang, K. Tan

引用次数: 244