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A Database Querying Language for Formulating Relational Queries on Small Devices
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作者 Ahmad Rohiza Abdul-Kareem Sameem 《Computer Technology and Application》 2011年第3期172-181,共10页
For small devices like the PDAs and mobile phones, formulation of relational database queries is not as simple as using conventional devices such as the personal computers and laptops. Due to the restricted size and r... For small devices like the PDAs and mobile phones, formulation of relational database queries is not as simple as using conventional devices such as the personal computers and laptops. Due to the restricted size and resources of these smaller devices, current works mostly limit the queries that can be posed by users by having them predetermined by the developers. This limits the capability of these devices in supporting robust queries. Hence, this paper proposes a universal relation based database querying language which is targeted for small devices. The language allows formulation of relational database queries that uses minimal query terms. The formulation of the language and its structure will be described and usability test results will be presented to support the effectiveness of the language. 展开更多
关键词 DATABASE query language relational queries small devices.
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Exploring features for automatic identification of news queries through query logs
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作者 Xiaojuan ZHANG Jian LI 《Chinese Journal of Library and Information Science》 2014年第4期31-45,共15页
Purpose:Existing researches of predicting queries with news intents have tried to extract the classification features from external knowledge bases,this paper tries to present how to apply features extracted from quer... Purpose:Existing researches of predicting queries with news intents have tried to extract the classification features from external knowledge bases,this paper tries to present how to apply features extracted from query logs for automatic identification of news queries without using any external resources.Design/methodology/approach:First,we manually labeled 1,220 news queries from Sogou.com.Based on the analysis of these queries,we then identified three features of news queries in terms of query content,time of query occurrence and user click behavior.Afterwards,we used 12 effective features proposed in literature as baseline and conducted experiments based on the support vector machine(SVM)classifier.Finally,we compared the impacts of the features used in this paper on the identification of news queries.Findings:Compared with baseline features,the F-score has been improved from 0.6414 to0.8368 after the use of three newly-identified features,among which the burst point(bst)was the most effective while predicting news queries.In addition,query expression(qes)was more useful than query terms,and among the click behavior-based features,news URL was the most effective one.Research limitations:Analyses based on features extracted from query logs might lead to produce limited results.Instead of short queries,the segmentation tool used in this study has been more widely applied for long texts.Practical implications:The research will be helpful for general-purpose search engines to address search intents for news events.Originality/value:Our approach provides a new and different perspective in recognizing queries with news intent without such large news corpora as blogs or Twitter. 展开更多
关键词 query intent News query News intent query classification Automaticidentification
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PAV-A-kNN: A Novel Approachable kNN Query Method in Road Network Environments
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作者 Kailai Zhou Weikang Xia Jiatai Wang 《Computers, Materials & Continua》 2025年第8期3217-3240,共24页
Ride-hailing(e.g.,DiDi andUber)has become an important tool formodern urban mobility.To improve the utilization efficiency of ride-hailing vehicles,a novel query method,called Approachable k-nearest neighbor(A-kNN),ha... Ride-hailing(e.g.,DiDi andUber)has become an important tool formodern urban mobility.To improve the utilization efficiency of ride-hailing vehicles,a novel query method,called Approachable k-nearest neighbor(A-kNN),has recently been proposed in the industry.Unlike traditional kNN queries,A-kNN considers not only the road network distance but also the availability status of vehicles.In this context,even vehicles with passengers can still be considered potential candidates for dispatch if their destinations are near the requester’s location.The V-Treebased query method,due to its structural characteristics,is capable of efficiently finding k-nearest moving objects within a road network.It is a currently popular query solution in ride-hailing services.However,when vertices to be queried are close in the graph but distant in the index,the V-Tree-based method necessitates the traversal of numerous irrelevant subgraphs,which makes its processing of A-kNN queries less efficient.To address this issue,we optimize the V-Tree-based method and propose a novel index structure,the Path-Accelerated V-Tree(PAV-Tree),to improve query performance by introducing shortcuts.Leveraging this index,we introduce a novel query optimization algorithm,PAVA-kNN,specifically designed to processA-kNNqueries efficiently.Experimental results showthat PAV-A-kNNachieves query times up to 2.2–15 times faster than baseline methods,with microsecond-level latency. 展开更多
关键词 k-nearest neighbor query ride-hailing services V-Tree shortest path
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Power Query与数据透视在工程计量自动汇总统计中的应用
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作者 季国军 陈华 +1 位作者 张佳龙 薛雯雯 《安装》 2025年第10期95-98,共4页
工程量计量与汇总统计工作贯穿于工程投标阶段、施工阶段和竣工阶段,工程计量后的汇总统计工作枯燥而繁琐,费时费力且容易出错,特别是当源数据发生变动时,汇总统计工作需重头再来,重复性机械性的人工汇总统计工作效率低下。本文结合实... 工程量计量与汇总统计工作贯穿于工程投标阶段、施工阶段和竣工阶段,工程计量后的汇总统计工作枯燥而繁琐,费时费力且容易出错,特别是当源数据发生变动时,汇总统计工作需重头再来,重复性机械性的人工汇总统计工作效率低下。本文结合实际项目案例,介绍了一种快速、准确、高效的工程量汇总统计方法,实现工程量计量汇总自动化更新,提高了工作效率与汇总统计的准确性。 展开更多
关键词 CAD POWER query 数据透视 统计汇总 数据分析
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Cryptanalysis and improvement to the quantum private query protocol for enhancing database privacy
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作者 Zhengda Shen Wenzhu Shao +4 位作者 Zhigang Li Xiaoyu Peng Nankun Mu Mahabubur Rahman Miraj Bin Liu 《Communications in Theoretical Physics》 2025年第6期122-128,共7页
In order to protect the privacy of the query user and database,some QKD-based quantum private query(QPQ)protocols were proposed.One example is the protocol proposed by Zhou et al,in which the user makes initial quantu... In order to protect the privacy of the query user and database,some QKD-based quantum private query(QPQ)protocols were proposed.One example is the protocol proposed by Zhou et al,in which the user makes initial quantum states and derives the key bit by comparing the initial quantum state and the outcome state returned from the database by ctrl or shift mode,instead of announcing two non-orthogonal qubits as others which may leak part secret information.To some extent,the security of the database and the privacy of the user are strengthened.Unfortunately,we find that in this protocol,the dishonest user could be obtained,utilizing unambiguous state discrimination,much more database information than that is analyzed in Zhou et al's original research.To strengthen the database security,we improved the mentioned protocol by modifying the information returned by the database in various ways.The analysis indicates that the security of the improved protocols is greatly enhanced. 展开更多
关键词 quantum private query quantum key distribution quantum cryptography
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Excel Power Query在中小型企业批量生成记账凭证中的应用
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作者 钱伟彬 《当代会计》 2025年第9期178-180,共3页
聚焦于中小型企业,深入探讨借助Excel Power Query工具批量生成记账凭证的方法。通过分析中小型企业记账凭证处理的现状,对比手工录入的会计电算化记账方式(以下简称手工录账)与借助Excel Power Query批量生成记账凭证的模式,阐述Excel ... 聚焦于中小型企业,深入探讨借助Excel Power Query工具批量生成记账凭证的方法。通过分析中小型企业记账凭证处理的现状,对比手工录入的会计电算化记账方式(以下简称手工录账)与借助Excel Power Query批量生成记账凭证的模式,阐述Excel Power Query在数据处理各环节的应用优势,详细介绍应用该工具批量生成记账凭证的具体步骤,并结合实际案例展示其应用效果。 展开更多
关键词 Excel Power query 记账凭证 批量生成 中小型企业
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基于XQuery的GML查询语言研究 被引量:12
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作者 兰小机 闾国年 +1 位作者 刘德儿 张书亮 《测绘科学》 CAS CSCD 北大核心 2005年第6期99-102,共4页
随着GML规范的不断完善及GIS软件厂商的广泛支持,越来越多的空间数据以GML格式存储,GML空间数据的查询已成为GIS研究的热点问题。传统的关系数据库查询语言SQL是针对平面的二维关系数据而设计的,并不适合XML/GML半结构化数据的查询;商品... 随着GML规范的不断完善及GIS软件厂商的广泛支持,越来越多的空间数据以GML格式存储,GML空间数据的查询已成为GIS研究的热点问题。传统的关系数据库查询语言SQL是针对平面的二维关系数据而设计的,并不适合XML/GML半结构化数据的查询;商品化GIS软件的查询系统只能查询自身的空间数据而无法查询其它GIS系统的空间数据;XML查询的研究为GML查询奠定了一定的基础。首先针对GML查询存在的问题,提出了扩展XQuery是GML查询语言实现的最佳选择;结合XML查询语言和空间数据查询语言,提出了GML查询语言的特征和GML查询语言系统框架;并根据GML空间数据的特点,以XML标准查询语言XQuery为基础,提出了XQuery空间扩展的内容;开发了GML空间数据查询语言GMLXQL,实现了GML空间数据的本原查询。 展开更多
关键词 GML查询 Xquery 空间查询语言 GML
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用Java来设计组件重用的Query方法 被引量:3
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作者 葛瀛龙 徐翀 +1 位作者 郑宁 胡昔祥 《计算机工程与应用》 CSCD 北大核心 2002年第20期103-106,共4页
文章所探讨的组件重用的Query方法是利用Java反射技术和Java数据库连接技术来完成叶数据库的查询操作。它将查询数据库的公共操作封装于一个组件中,使编程工作者在具体编程工作中能方便地重复使用它们,以求简化编程工作。
关键词 JAVA语言 设计 组件重用 query方法 EJB组件
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Semantic-based query processing for relational data integration 被引量:1
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作者 苗壮 张亚非 +2 位作者 王进鹏 陆建江 周波 《Journal of Southeast University(English Edition)》 EI CAS 2011年第1期22-25,共4页
To solve the query processing correctness problem for semantic-based relational data integration,the semantics of SAPRQL(simple protocol and RDF query language) queries is defined.In the course of query rewriting,al... To solve the query processing correctness problem for semantic-based relational data integration,the semantics of SAPRQL(simple protocol and RDF query language) queries is defined.In the course of query rewriting,all relative tables are found and decomposed into minimal connectable units.Minimal connectable units are joined according to semantic queries to produce the semantically correct query plans.Algorithms for query rewriting and transforming are presented.Computational complexity of the algorithms is discussed.Under the worst case,the query decomposing algorithm can be finished in O(n2) time and the query rewriting algorithm requires O(nm) time.And the performance of the algorithms is verified by experiments,and experimental results show that when the length of query is less than 8,the query processing algorithms can provide satisfactory performance. 展开更多
关键词 data integration relational database simple protocol and RDF query language(SPARQL) minimal connectable unit query processing
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Optimization of RDF link traversal based query execution 被引量:2
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作者 朱艳琴 花岭 《Journal of Southeast University(English Edition)》 EI CAS 2013年第1期27-32,共6页
Aiming at the problem that only some types of SPARQL ( simple protocal and resource description framework query language) queries can be answered by using the current resource description framework link traversal ba... Aiming at the problem that only some types of SPARQL ( simple protocal and resource description framework query language) queries can be answered by using the current resource description framework link traversal based query execution (RDF-LTE) approach, this paper discusses how the execution order of the triple pattern affects the query results and cost based on concrete SPARQL queries, and analyzes two properties of the web of linked data, missing backward links and missing contingency solution. Then three heuristic principles for logic query plan optimization, namely, the filtered basic graph pattern (FBGP) principle, the triple pattern chain principle and the seed URIs principle, are proposed. The three principles contribute to decrease the intermediate solutions and increase the types of queries that can be answered. The effectiveness and feasibility of the proposed approach is evaluated. The experimental results show that more query results can be returned with less cost, thus enabling users to develop the full potential of the web of linked data. 展开更多
关键词 web of linked data resource description framework link traversal based query execution (RDF-LTE) SPARQL query query optimization
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Query Expansion for Chinese Information Retrieval by Using a Decaying Co-occurrence Model 被引量:3
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作者 贺宏朝 何丕廉 +1 位作者 高剑峰 黄昌宁 《Transactions of Tianjin University》 EI CAS 2002年第3期183-186,共4页
Query expansion with thesaurus is one of the useful techniques in modern information retrieval (IR). In this paper, a method of query expansion for Chinese IR by using a decaying co-occurrence model is proposed and re... Query expansion with thesaurus is one of the useful techniques in modern information retrieval (IR). In this paper, a method of query expansion for Chinese IR by using a decaying co-occurrence model is proposed and realized. The model is an extension of the traditional co-occurrence model by adding a decaying factor that decreases the mutual information when the distance between the terms increases. Experimental results on TREC-9 collections show this query expansion method results in significant improvements over the IR without query expansion. 展开更多
关键词 query expansion Chinese language information retrieval
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AnyQuery:网格环境下基于服务的分布式查询处理系统 被引量:6
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作者 石柯 林海华 徐彬 《小型微型计算机系统》 CSCD 北大核心 2006年第8期1432-1438,共7页
AnyQuery是一种适用于网格环境、基于服务的分布式查询处理系统,使用统一的数据格式(可扩展标记语言)来表示和传输数据,所有组成模块以网格服务的形式实现,网格服务之间通过标准的接口进行通信.这种接口和实现分离技术屏蔽了不同数据库... AnyQuery是一种适用于网格环境、基于服务的分布式查询处理系统,使用统一的数据格式(可扩展标记语言)来表示和传输数据,所有组成模块以网格服务的形式实现,网格服务之间通过标准的接口进行通信.这种接口和实现分离技术屏蔽了不同数据库及其运行节点的差异,为用户提供一致的虚拟关系数据视图和分布式数据查询支持.在分析和研究已有的并行数据库和分布式数据库查询技术的基础上,AnyQuery提出和实现了一种适用于动态网格环境的分布式查询计划生成和执行算法,该算法能够根据网格环境中各节点及其连接网络的实际情况确定查询计划,支持跨数据库的连接查询.基于Globus3.0开发了AnyQuery的原型系统,性能测试表明该系统具有较好的可扩展性,尤其适合计算密集型的复杂查询. 展开更多
关键词 分布式查询 服务 网格
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XQuery——一种全新的XML查询语言 被引量:6
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作者 金玉玲 陈培久 裘江南 《情报学报》 CSSCI 北大核心 2002年第4期445-449,共5页
随着XML被广泛接受和使用 ,如何从XML数据源中准确有效地查询所需信息 ,也就变得越来越重要。本文介绍了一种全新XML查询语言—XQuery ,阐述了XQuery的结论、应用范围。
关键词 XML Xquery XML查询语言 电子商务 结构 应用范围
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基于JQuery的自动完成功能的实现 被引量:3
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作者 王波 王瀚波 《三门峡职业技术学院学报》 2010年第3期102-106,共5页
当客户在利用Goolge或Baidu搜索引擎在网上搜索信息时,自动完成功能给大家带来了很大的便利。随着Ajax技术的迅速发展,自动完成功能在不同的框架中都得到了一定程度的实现。以某精密机械有限公司ERP系统的制定年业务计划模块为例,详细... 当客户在利用Goolge或Baidu搜索引擎在网上搜索信息时,自动完成功能给大家带来了很大的便利。随着Ajax技术的迅速发展,自动完成功能在不同的框架中都得到了一定程度的实现。以某精密机械有限公司ERP系统的制定年业务计划模块为例,详细介绍通过JQuery-aucomplete插件和基于文本的数据交换格式JSON实现基于JQuery的自动完成功能的方法。 展开更多
关键词 AJAX query JSON 自动完成
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企业信息集成中XQuery引擎的查询优化 被引量:2
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作者 毕蓉蓉 刘渊 翟学敏 《计算机工程与应用》 CSCD 北大核心 2008年第29期161-164,共4页
通过分析研究已有的XQuery引擎和XQ uery查询优化的方法,从减少编译时间和执行时间角度出发,提出了一种基于XQuery语句自身优化的新型综合性优化方法,经过XQuery中某常见查询进行仿真实验,可以说明该新型综合优化方法有较强的优势,可以... 通过分析研究已有的XQuery引擎和XQ uery查询优化的方法,从减少编译时间和执行时间角度出发,提出了一种基于XQuery语句自身优化的新型综合性优化方法,经过XQuery中某常见查询进行仿真实验,可以说明该新型综合优化方法有较强的优势,可以大大地提高XQuery引擎的查询效率。 展开更多
关键词 企业信息集成 引擎 查询优化 查询重写
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APPROXIMATE QUERY AND CALCULATION OF RNN_k BASED ON VORONOI CELL 被引量:1
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作者 郝忠孝 李博涵 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第2期154-161,共8页
Reverse k nearest neighbor (RNNk) is a generalization of the reverse nearest neighbor problem and receives increasing attention recently in the spatial data index and query. RNNk query is to retrieve all the data po... Reverse k nearest neighbor (RNNk) is a generalization of the reverse nearest neighbor problem and receives increasing attention recently in the spatial data index and query. RNNk query is to retrieve all the data points which use a query point as one of their k nearest neighbors. To answer the RNNk of queries efficiently, the properties of the Voronoi cell and the space-dividing regions are applied. The RNNk of the given point can be found without computing its nearest neighbors every time by using the rank Voronoi cell. With the elementary RNNk query result, the candidate data points of reverse nearest neighbors can he further limited by the approximation with sweepline and the partial extension of query region Q. The approximate minimum average distance (AMAD) can be calculated by the approximate RNNk without the restriction of k. Experimental results indicate the efficiency and the effectiveness of the algorithm and the approximate method in three varied data distribution spaces. The approximate query and the calculation method with the high precision and the accurate recall are obtained by filtrating data and pruning the search space. 展开更多
关键词 computational geometry approximation query filtrating reverse k nearest neighbor (RNNk) Voronoi cell
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XML查询语言XQuery的研究与实现 被引量:5
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作者 华珊珊 谢铉洋 《计算机技术与发展》 2009年第4期48-50,共3页
XQuery是一种对XML结构的文档和数据进行查询的语言。在对该查询语言规范体系分析、理解和研究的基础上,提出了支持W3C的XQuery语言的查询处理引擎的体系结构。针对各个输入输出和处理模块按数据流的方式逐一进行分析,对整个系统的运行... XQuery是一种对XML结构的文档和数据进行查询的语言。在对该查询语言规范体系分析、理解和研究的基础上,提出了支持W3C的XQuery语言的查询处理引擎的体系结构。针对各个输入输出和处理模块按数据流的方式逐一进行分析,对整个系统的运行状态做了一个总体的介绍。按照这个体系结构,一个XQuery查询处理引擎已经被实现。 展开更多
关键词 XML Xquery 查询 处理引擎
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XQuery语言的实现 被引量:4
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作者 谢荣传 谢铉洋 《安徽大学学报(自然科学版)》 CAS 北大核心 2005年第1期23-26,共4页
首先分析了万维网联合会(W3C)提出的XML查询语言XQuery语言的特点,提出了支持W3C的XQuery语言查询处理引擎的体系结构。简要介绍了基于该体系结构所实现的XQuery处理引擎的词法/语法解析、语法转换、类型检查和分析、赋值计算等四个处... 首先分析了万维网联合会(W3C)提出的XML查询语言XQuery语言的特点,提出了支持W3C的XQuery语言查询处理引擎的体系结构。简要介绍了基于该体系结构所实现的XQuery处理引擎的词法/语法解析、语法转换、类型检查和分析、赋值计算等四个处理阶段涉及的主要内容。 展开更多
关键词 Xquery语言 W3C XML查询 查询处理 体系结构 引擎 万维网 语法 赋值 支持
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基于XQuery查询优化的研究 被引量:2
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作者 施振佺 曹渠江 《计算机应用与软件》 CSCD 北大核心 2008年第11期86-88,共3页
XML已经成为网络上信息描述和信息交换的标准,随着XML应用得越来越广泛,人们提出了多种XML数据的查询方法。但是,很多查询方法都有各自的局限性。利用有意义的最小公共实体结构EntityInMLCAS(Entity In Meaning Lowest Common An- cesto... XML已经成为网络上信息描述和信息交换的标准,随着XML应用得越来越广泛,人们提出了多种XML数据的查询方法。但是,很多查询方法都有各自的局限性。利用有意义的最小公共实体结构EntityInMLCAS(Entity In Meaning Lowest Common An- cestor Structure)原理,提出一种优化查询方法。同时采用堆栈技术的方法对XML文档结点树进行自顶向下的遍历,该方法大大提高了优化查询的速度。 展开更多
关键词 XML Xquery EntityInMLCAS 结构化查询
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Processing and optimization of UMQL-based multimedia queries
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作者 吴宗大 曹忠升 +1 位作者 王元珍 李桂玲 《Journal of Southeast University(English Edition)》 EI CAS 2009年第3期320-325,共6页
Through the mapping from UMQL ( unified multimedia query language) conditional expressions to UMQA (unified multimedia query algebra) query operations, a translation algorithm from a UMQL query to a UMQA query pla... Through the mapping from UMQL ( unified multimedia query language) conditional expressions to UMQA (unified multimedia query algebra) query operations, a translation algorithm from a UMQL query to a UMQA query plan is put forward, which can generate an equivalent UMQA internal query plan for any UMQL query. Then, to improve the execution costs of UMQA query plans effectively, equivalent UMQA translation formulae and general optimization strategies are studied, and an optimization algorithm for UMQA internal query plans is presented. This algorithm uses equivalent UMQA translation formulae to optimize query plans, and makes the optimized query plans accord with the optimization strategies as much as possible. Finally, the logic implementation methods of UMQA plans, i.e., logic implementation methods of UMQA operators, are discussed to obtain useful target data from a muifirnedia database. All of these algorithms are implemented in a UMQL prototype system. Application results show that these query processing techniques are feasible and applicable. 展开更多
关键词 multimedia database multimedia query language query optimization unified multimedia query language
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