一种基于XML的Web数据集成方案

介绍了Web环境下异构数据集成技术产生的背景和研究目的以及相关的概念、技术和方法,针对XML作为合适的数据交换格式的特点介绍了基于XML的信息集成的关键因素,提出了一种基于XML的Web数据集成操作模型,并讨论了该模型在Web数据集成时数据交换和共享过程,给出了集成构架的结构及组成。     

Rewriting of visibly pushdown languages for XML data integration

In this work, we focus on XML data integration by studying rewritings of XML target schemas in terms of source schemas. Rewriting is very important in data integration systems where the system is asked to find and assemble XML documents from the data sources and produce documents that satisfy a target schema.As schema representation, we consider Visibly Pushdown Automata (VPAs), which accept Visibly Pushdown Languages (VPLs). The latter have been shown to coincide with the family of (word-encoded) regular tree languages, which are the basis of formalisms for specifying XML schemas. Furthermore, practical semi-formal XML schema specifications (defined by simple pattern conditions on XML) compile into VPAs that are exponentially more concise than other representations based on tree automata.Notably, VPLs enjoy a “well-behavedness” that facilitates us in addressing rewriting problems for XML data integration. Based on VPAs, we positively solve these problems, and present detailed complexity analyses.     

基于XML技术的数据集成解决方案的研究与应用

企业为了提高相互之间的合作程度以及自身的竞争力，常常需要将企业内部或者企业之间的应用系统进行集成，数据集成作为系统集成的基础，它的成功与否直接影响到系统集成的成败，文章首先提出了一种基于XML技术的数据集成解决方案，研究了XML技术在数据整合与交换方面的原理与实现，然后结合它在“银保”合作中的应用，说明了基于XML技术的数据集成解决方案在实际应用中的可行性和优势。     

Converting XML DTDs to UML diagrams for conceptual data integration

Extensible Markup Language (XML) is fast becoming the new standard for data representation and exchange on the World Wide Web, e.g., in B2B e-commerce. Modern enterprises need to combine data from many sources in order to answer important business questions, creating a need for integration of web-based XML data. Previous web-based data integration efforts have focused almost exclusively on the logical level of data models, creating a need for techniques that focus on the conceptual level in order to communicate the structure and properties of the available data to users at a higher level of abstraction. The most widely used conceptual model at the moment is the Unified Modeling Language (UML).

This paper presents algorithms for automatically constructing UML diagrams from XML DTDs, enabling fast and easy graphical browsing of XML data sources on the web. The algorithms capture important semantic properties of the XML data such as precise cardinalities and aggregation (containment) relationships between the data elements. As a motivating application, it is shown how the generated diagrams can be used for the conceptual design of data warehouses based on web data, and an integration architecture is presented. The choice of data warehouses and On-Line Analytical Processing as the motivating application is another distinguishing feature of the presented approach.     

基于XML的虚拟法异构数据集成方法研究*

随着信息技术的发展,Web上的数据日趋成为当今数据的主流,但是Web上的数据多是异构的,而越来越多的人需要访问各种异构数据,为了满足这种需求,必须有一种系统能够支持异构数据集成。异构数据集成的方法有很多,给出一个基于XML的虚拟法异构数据集成系统体系结构,引入虚拟法,提出用虚拟法进行异构数据集成;最后引入数据清洗技术,能够较好地解决异构数据的集成。     

数据集成中XML Schema到关系模式的转换方法

根据XML Schema中组件的定义及组件之间的嵌套关系,建立一系列从XML Schema转换成关系模式的结构映射规则和语义映射规则。基于这些规则实现一种转换算法,从Schema中提取出关系模式,并且证明映射得到的关系模式满足4NF。结果表明得到的关系模式不仅包含了XML Schema中所有的结构和内容信息,还能保留大部分语义约束信息,减少存储冗余。     

基于领域本体和关系模型的XML语义集成方法研究

由于缺乏足够的语义信息,不同模式的XML数据之间很难进行互操作。针对油气井工程中的XML数据集成需求,借助领域全局本体,提出一种模式无关的XML语义集成方法。该方法首先在XML Path路径与领域本体之间进行语义映射,屏蔽其模式差异;然后,按照模型映射方法将XML存储为关系数据;最后通过查询重写将SPARQL转换为SQL语句,实现语义查询。该方法对XML模式进行语义标注,利用关系数据库存储与查询XML数据,能有效处理领域XML数据的语义集成。     

Semantic and structural similarities between XML Schemas for integration of ubiquitous healthcare data

Currently, a lot of recent electronic health records are based on XML documents. In order to integrate these heterogeneous XML medical documents efficiently, studies on finding structure and semantic similarity between XML Schemas have been exploited. The main problem is how to harvest the most appropriate relatedness to combine two schemas as a global XML Schema for reusing and referring purposes. In this paper, we propose the novel resemblance measure that concurrently considers both structural and semantic information of two specific healthcare XML Schemas. Specifically, we introduce new metrics to compute the datatype and cardinality constraint similarities, which improve the quality of the semantic assessment. On the basis of the similarity between each element pair, we put forward an algorithm to calculate the similarity between XML Schema trees. Experimental results lead to the conclusion that our methodology provides better similarity values than the others with regard to the accuracy of semantic and structure similarities.     

Cross-platform integration with XML and SOAP

The current rage for middleware has provided tremendous opportunities for those who love to build complex distributed software applications. Interoperability is no longer a fringe movement; it's become mainstream. The big three-Microsoft, IBM, and Sun Microsystems-are now investing considerable resources into interoperability research. I tackle the abstract concept of software interoperability and how the Extensible Markup Language (XML) and Simple Object Access Protocol (SOAP) can assist in integrating business applications. Together with the concept of Web services, these standards could provide an alternative to what organizations do today: rely on the batch export of data to integrate software applications     

Business to business interoperability: A current review of XML data integration standards

Despite the dawn of the XML era, semantic interoperability issues still remain unsolved. As various initiatives trying to address how the underlying business information should be modelled, named and structured are being realised throughout the world, the importance of moving towards a holistic approach in eBusiness magnifies. In this paper, an attempt to clarify between the standards prevailing in the area is performed and the XML Data Standards providing generic XML Schemas are presented. Based on this “XML Data Standards Map”, a multi-faceted classification mechanism is proposed, leading to an extensible taxonomy of standards. A set of facets is analyzed for each standard, allowing for their classification based on their scope, completeness, compatibility with other standards, openness, ability to modify the schemas and maturity, to name a few. Through populating and querying this multi-faceted classification, a common understanding of Data Integration Standards can be ensured and the choice of a standard according to the requirements of each business can be systematically addressed.     

XML企业信息集成平台的实现及应用

随着XML技术的不断发展,XML技术在企业信息建设中发挥了越来越重的作用,本文提出了一种以XML技术为基础的信息集成方案,以XML文件作为存储格式,XQUERY语言作为查询语言,以完全XML的格式向应用层提供数据支持。这种方式可以集成更多类型的数据源,并且可以用与信息发布,格式转换,上层应用等多种用途。     

利用JMS和XML实现系统集成

说明系统集成是信息化的必然趋势，提出用JMS－XML构建系统集成体系，具体阐述了JMS和XML的体系和实现，最后，运用JMS－XML体系来构建一个实例。     

XML data mining

With the spreading of XML sources, mining XML data can be an important objective in the near future. This paper presents a project focussed on designing a general‐purpose query language in support of mining XML data. In our framework, raw data, mining models and domain knowledge are represented by way of XML documents and stored inside native XML databases. Data mining (DM) tasks are expressed in an extension of XQuery. Special attention is given to the frequent pattern discovery problem, and a way of exploiting domain‐dependent optimizations and efficient data structures as deeper as possible in the extraction process is presented. We report the results of a first bunch of experiments, showing that a good trade‐off between expressiveness and efficiency in XML DM is not a chimera. Copyright © 2009 John Wiley & Sons, Ltd.     

基于XML的温盐深数据Schema设计

XML是W3C组织于1998年2月发布的一种标记语言标准,其具有易于扩展、结构性强、交互性好、语义丰富、基于内容的数据标识、可格式化、易于处理、与平台无关的特点,使得数据层在XML技术的支持下得到统一。通过对海洋温盐深数据进行结构分析,本文设计了温盐深数据XML Schema,定义了温盐深数据的XML数据结构。     

Double-layered schema integration of heterogeneous XML sources

Schema integration aims to create a mediated schema as a unified representation of existing heterogeneous sources sharing a common application domain. These sources have been increasingly written in XML due to its versatility and expressive power. Unfortunately, these sources often use different elements and structures to express the same concepts and relations, thus causing substantial semantic and structural conflicts. Such a challenge impedes the creation of high-quality mediated schemas and has not been adequately addressed by existing integration methods. In this paper, we propose a novel method, named XINTOR, for automating the integration of heterogeneous schemas. Given a set of XML sources and a set of correspondences between the source schemas, our method aims to create a complete and minimal mediated schema: it completely captures all of the concepts and relations in the sources without duplication, provided that the concepts do not overlap. Our contributions are fourfold. First, we resolve structural conflicts inherent in the source schemas. Second, we introduce a new statistics-based measure, called path cohesion, for selecting concepts and relations to be a part of the mediated schema. The path cohesion is statistically computed based on multiple path quality dimensions such as average path length and path frequency. Third, we resolve semantic conflicts by augmenting the semantics of similar concepts with context-dependent information. Finally, we propose a novel double-layered mediated schema to retain a wider range of concepts and relations than existing mediated schemas, which are at best either complete or minimal, but not both. Performed on both real and synthetic datasets, our experimental results show that XINTOR outperforms existing methods with respect to (i) the mediated-schema quality using precision, recall, F-measure, and schema minimality; and (ii) the execution performance based on execution time and scale-up performance.     

XML的关系化存储及与关系数据库的数据转换

随着不断增长的基于XML应用的出现,如何在数据库中可靠、有效地存储XML文档以及XML和数据库间的数据转换技术变得越来越重要。讨论了基于模式驱动的XML与关系数据库的数据映射,给出了其基本原理和实例,并且分析了采用该技术实现的一个与数据库平台无关的、支持多模式和多种转换方式的应用系统,给出了该系统的设计和实现方案。其原型的测试结果表明,该系统的原理和设计是可行的和有效的。     

XML seen as integral to application integration

Many companies have a wealth of information in their databases and applications, and want to leverage these assets. They are beginning to see that XML could help them do this by providing a standard data format for cross-platform information exchange. XML thus offers a powerful new way to integrate new and existing applications within companies. Today much of that linking must be done using enterprise application integration software, which is often complex and quite costly. Developers may have to translate legacy APIs to new component APIs or change flow data and workflow processes are structured to permit data exchange between incompatible applications. Analysts and some early adopters say XML will help simplify this complex, labor-intensive process because it lets developers precisely identify pieces of data on the basis of content     

XML queries and algebra in the Enosys integration platform

We describe the Enosys XML integration platform, focusing on the query language, algebra, and architecture of its query processor. The platform enables the development of eBusiness applications in customer relationship management, e-commerce, supply chain management, and decision support. These applications often require that data be integrated dynamically from multiple information sources. The Enosys platform allows one to build (virtual and/or materialized) integrated XML views of multiple sources, using XML queries as view definitions. During run-time, the application issues XML queries against the views. Queries and views are translated into the XCQL algebra and are combined into a single algebra expression/plan. Query plan composition and query plan decomposition challenges are faced in this process. Finally, the query processor lazily evaluates the result, using an appropriate adaptation of relational database iterator models to XML. The paper describes the platform architecture and components, the supported XML query language and the query processor architecture. It focuses on the underlying XML query algebra, which differs from the algebras that have been considered by W3C in that it is particularly tuned to semistructured data and to optimization and efficient evaluation in a system that follows the conventional architecture of database systems.     

基于XML技术的异构关系数据库集成模型

为了有效解决网络环境中异构数据库数据集成问题,分析了异构数据库集成的现状,提出了一种基于XML技术的异构关系数据库数据集成模型.该模型由异构数据库层、集成中间件层,应用层3部分组成;阐述了该模型各个部分的功能,讨论了集成中间件层的实现;详细地介绍了数据库和XML之间相互映射规则,并给出了它们之间的具体转换过程.在集成中间件的基础上,设计了某信息管理服务系统软件,表明了该中间件的可行性.     

Numerical constraints on XML data

Boundaries occur naturally in everyday life. This paper introduces numerical constraints into the framework of XML to take advantage of the benefits that result from the explicit specification of such boundaries. Roughly speaking, numerical constraints restrict the number of elements in an XML data fragment based on the data values of selected subelements. Efficient reasoning about numerical constraints provides effective means for predicting the number of answers to XQuery and XPath queries, the number of updates when using the XQuery update facility, and the number of encryptions or decryptions when using XML encryption. Moreover, numerical constraints can help to optimise XQuery and XPath queries, to exclude certain choices of indices from the index selection problem, and to generate views for efficient processing of common queries and updates.We investigate decision problems associated with numerical constraints in order to capitalise on the range of applications in XML data processing. To begin with we demonstrate that the implication problem is strongly coNP-hard for several classes of numerical constraints. These sources of potential intractability direct our attention towards the class of numerical keys that permit the specification of positive upper bounds. Numerical keys are of interest as they are reminiscent of cardinality constraints that are widely used in conceptual data modelling. At the same time, they form a natural generalisation of XML keys that are popular in XML theory and practice. We show that numerical keys are finitely satisfiable and establish a finite axiomatisation for their implication problem. Finally, we propose an algorithm that decides numerical key implication in quadratic time using shortest path methods.