【摘要】 <正> 包装器是自治异构数据源集成系统中的重要组成部分。随着与XML有关的标准不断制定和完善,越来越多的数据被用XML表示,同时必须注意的一个事实是,目前和在一个可以预见的未来,大部分应用系统,甚至是新的基于Web的应用系统,仍然将关系数据库系统作为数据存储和查询的首选。关系数据库系统的可靠性、技术的成熟性、丰富的工具、高性能等,都决定了这一点。本文探讨在自治异构数据源集成系统情境下,如何将XML查询翻译成SQL查询,如何将关系数据转换为XML数据表示。更多还原

【Abstract】 XML is emerging as a de facto standard for data representation and exchange on the Web. However,currently and in the forseeable future, most data will continue to be stored in and retrived from relational database systems. It is mainly decided by the reliabilty,maturity,efficience and lots of tools with RDBMS. Many challenges exist as converting flat,normalized relational data into hierachical,unnormalized XML data. Based on XML technologies,the paper addresses a novel and lightweight approach to translate XML queries into SQL requests and transforms the re-tured tuples into XML representation in the context of data integration system. A wrapper for relational soruces was developed based on the approach. The paper is an important part of the research on integrated query processing over hetergeneous data sources.更多还原