An Efficient Middleware for Storing and Querying XML Data in Relational Database Management System

摘要

Problem statement: In this study, we propose a middleware that provides a transformation utility for storing and querying XML data in relational databases using model mapping method. Approach: To store XML documents in RDBMS, several mapping approaches can be used. We chose structure independent approach. In this middleware the model mapping method XParent and free of cost available technologies MYSQL, PhpMyAdmin and PHPclasses are used as examples. Results: This middleware stores XML tables and does not require a direct extension of SQL thus this middleware can be used with any relational databases management system with little changes in the middleware interface. The middleware offers two alternative methods -namely XParent and XReal- for storing XML in the database. Conclusion: The key to proposed middleware is to store XML document in a relational database through a user interface and with an XPath query processor. We present a comparative experimental study on the performance of insertion and retrieval of two types of XML documents with a set of XPath queries executed though the XPath. XML and Relational databases cannot be kept separately because XML is becoming the universal standard data format for the representation and exchanging the information whereas most existing data lies in RDBMS and their power of data capabilities cannot be degraded so the solution to this problem a middleware prototype is required. The proposed schema dependent solutions have a drawback that evens a small change in the logical structure of XML documents influence on the database schemas and several problems occur during the updating process. A new efficient data middleware is proposed in the study to face these issues.