【作者】 边继龙；

【导师】 王霓虹；

【作者基本信息】 东北林业大学 ， 计算机应用技术， 2008， 硕士

【摘要】 近年来,计算机和网络技术的发展呈加速态势,但各种应用的核心——数据,仍以不同形式存储在不同的系统中,分而不聚,聚而不合,呈分布异构状态。随着应用需求的不断增加,越来越多的用户希望能够透明地获取和处理来自这些海量信息源中的有用数据,实现多个软硬件系统以及不同信息源之间的互操作。然而,这些信息源物理上可能分布在异构环境的多个自治域中,有着不同的数据格式、存储方式、访问控制策略,逻辑上则可能在数据模型、操纵语言和数据语义等方面存在着很大差异。同时,这些信息源的可共享性、共享方式、共享内容等也可能随时发生变化。设计一个支持公共数据模型、统一查询语言和可更新的异构数据源集成中间件系统,是实现这种交互操作的一种较好办法。异构数据源集成中间件系统可以屏蔽现在已有的各种异构数据管理系统不同的访问方法和用户界面,给用户呈现一个访问多种异构数据源的公共接口,提供一个集成处理多种数据源、整合多个数据查询结果的信息交互处理平台。本文研究了异构数据集成的相关理论和技术,结合XML技术的优势,提出了一种基于中间件的异构信息集成系统,解决了对异构数据源的查询和更新。其主要思想是:(1)把XML视图查询映射成一组关系视图查询;(2)把在XML视图上的更新映射成在相应关系视图上的更新;(3)把对关系视图的查询和更新映射成对基本表的查询和更新,最后把对基本表的操作分发到各个数据源。基于上述理论和实验研究成果,研制和开发了一个基于中间件异构信息集成系统,它能够提供对Oracle、Sybase、DB2等关系数据库系统的透明访问。更多还原

【Abstract】 The development of computer and network technologies speeds up in recent years.But the data, which are the core of all applications, are still stored in different systems with different manners and live by themselves in distributed and heterogeneous environment. With the steady increase of application requirements, more and more people want to access and manipulate the useful information among multiple massive information sources and achieve the interoperability of multiple computer systems and different information sources. However, these data sources may not only geographically locate at multiple autonomous domains in heterogeneous environment with different data formats, storage modes and access control policies, but also logically differ from each other in data models, manipulation languages and data semantics. Moreover, the sharing ability, modes and contents of the sources may change at any time. So, designing a heterogeneous data source integration mediator system (HDSIMS) supporting the common data model , a uniform query language and update is a better way to implement this type of interoperation. HDSIMS can hide most of the differences of access methods and user interfaces of multiple heterogeneous data management systems. It also provides an information interoperating platform as a common interface to access multiple heterogeneous data sources and combine the intermediate query results from these sources..Combined with the advantage of XML,This paper disscusses some theories and technology of heterogeneous data source integration and presents a heterogeneous data source integration mediator system solving query and update against multi-heterogeneous data sources the basic idea is: we (i) map an XML view query to a set of relational view queries; (ii) map updates over the XML view to updates over the corresponding relational views; and (iii) map query and update over relational views to the underlying relational tables and dispatch them to data sources. The above theoretical principles and prctical techniques are adopt for developing a heterogeneous data source integration mediator system which provides the transparent access to heterogenous data sources such as Oracle, Sybase, DB2.更多还原