多数据库系统中基于XIDM的模式映射方法研究

Research on XIDM-Based Schema Mapping in Multidatabase Systems

建立多数据库系统中多种模式间的映射是多数据库解决模式异构性的关键 ,而选用一种适用于这些映射的集成数据模型又是模式映射的基础 为了集成数据库、文件系统、Web文档等多种异构系统中的数据 ,提出了一种基于XML的集成数据模型 (XIDM)作为多数据库系统的公共数据模型 基于XIDM模型 ,给出了全局模式与输出模式、输出模式与局部模式之间的模式映射方法 ,并对全局映射和局部映射在多数据库原型系统Panorama中的实现进行了示例

Establishing schema mappings among different schemas is a key to solve the problem of schema heterogeneity in multidatabase systems Since an integrated data model suitable for the transformation is the basis of schema mappings, an XML based integrated data model (XIDM) is presented as the common data model to integrate multiple heterogeneous data sources such as database tables, files and web documents in a multidatabase system An XIDM based approach of schema mapping among global schemas, export schemas, and local schemas is also given Then, the illustration and implementation of global and local mappings in multidatabase prototype—Panorama system are shown, and finally, the performance evaluation and analysis of XIDM based schema mapping are also discussed