The Research Of Format Conversion Technology With Manufacturing Information Based On XML

In the past years,XML(eXtensible Markup Language) has been one of the standards for data exchange on the Web.It is widely applied in many fields.But during the process of enterprise informationization,relational database systems are widely used and are playing some significant roles in the data management of enterprises with their mature technology,powerful data management,the reliable and stable concurrent control.And a lot of manufacturing information is stored in relational database systems.Often relational database are used to store and manage data and XML data are used as information exchange medium.Transform data from existing relational database into data type of XML has become the pivotal problem for data format exchange with manufacture information.We research the following topics:relation-tree model with semantic keys, mapping relation schema to XML schema,translating relational data into XML data while preserving intrinsic semantic relationships among the relation data.As a result, we propose effective method and realizable technology..(1)This paper presents a relation-tree model which includes semantic keys.And an algorithm is designed to map relational schema to this relation-tree.This mapping algorithm not only map relational schema to relation-tree with semantic keys but also guarantee the completeness and validity of the set of semantic keys after transform. Then,the XML schema is mapped based on this relation-tree and a XML-Schema is designed which describe the XML schema and correspond to the relational schema.It is proved that this method is valid and efficient for keeping semantic restriction and strengthening data coupling.(2)When data is exchanged on the Web,the XML schemas of the two entities (their standards) must be considered.If the source data is relational data,it needs to be published into XML data conforming to the schema of the target entity.So,a transform method about how to map the XML schema to a nested data mapping structure is studied based on the XML schema restriction which has been studied before and described by XML-Schema.Through construct corresponding SQL query sentence in the nested data mapping structure,relational data could be acquired.Then put those acquired relational data to the fight places of XML document,the translation from relational data to XML data is finished.(3)A prototype system named as RDB2XML is designed by Java and B/S (Browser/Server) frame as a facility for practical applications as well to implement the above ideas and methods.The interrelated technique that transforming relational schema data to XML schema data is studied in which the relational database systems is taken as the bottom storing medium.The thesis establish two strategies of publishing relational data to XML data combining mapping relational schema to XML schema with dynamic database queries.