Research On Web-based Data Integration And Multi-dimensional Analytical Model

With the rapid development of web and database technique, the demand for data integration is becoming urgently as more and more information sources appear in modern enterprises. In many situations a logical integration of data is preferable since some data is inherently not suited for being stored in a physically integrated data warehouse. The integration of web data must be supported by semi-structured data model and data model extraction technique. To search for a semi-structured data model to describe the web data distinctly is the key to solve the integration problem, and the extraction technique is applied to extract semi-structured data model from the existing data.In the paper, the study of the data integration is based on the project "the small and middle enterprise's information platform". Aiming at the complex representation of heterogeneous data, we employ the XML to integrate and analyze web data. A scheme, designed for integration of heterogeneous data sources based on virtual integration plan in an extensible way, is put forward in the paper. An XML-based data model, named XCDM (XML-based common data model), is proposed as the common data model for integration. The system can integrate various heterogeneous data sources, ranging from database systems, file systems, to hypertext files in World-Wide-Web. Any other data source, if wrapped according to the specified way, can be integrated into the system, whenever necessary. The architecture, XCDM, wrapper, query processing, user diagram design are introduced in detail in the paper.In order to query and update heterogeneous data sources, we present formal schemas of XML, relational data schema, object data schema and HTML document, and describe a kind of flexible formal mapping between these data schemas and XML. The paper develops an approach to model a multi-dimensional cube with XML, which emerges as a universal format for data exchange on the web and can make the analysis of web data flexible and reusable. We introduce the method which can save the multi-dimensional instance with XML documents and construction procedure of cubes. Multi-dimensional analytical model is transformed into objects, which is beneficial to OLAP and web data mining.