XML-REG: Transforming XML Into Relational Using Hybrid-Based Mapping Approach

eXtensible Markup Language (XML) is one of the most used standards for information sharing between applications and devices, both on the internet and local network. However, relational database (RDB) has been used by many enterprises as their data management system and will require an amount of cost to change the system completely, if they are to change to XML technology solely. Thus, a mapping scheme is required to provide seamless integration on bridging XML technologies and RDBs. In this paper, an efficient model-based mapping scheme named XML-REG is proposed. The XML document will first be read and parsed into the parser, namely Streaming API for XML (StAX) parser. Then, each node will then be assigned with unique identification label to show the exact position of nodes in the document. Subsequently, by employing the proposed algorithm, data will then be transformed into tables in the RDB storage. As the result, two tables, namely (i) value table to store information carried by text node of the document, and (ii) path table to store the hierarchy structure of the document will be created. Experimental evaluations demonstrated that XML-REG outperformed some existing approaches, such as Mini-XML, XAncestor, XMap and XRecursive in terms of data storage size, mapping time and query retrieval time. In addition, the scalability test has also been conducted to show the capability of these approaches in supporting huge datasets, by scaling the DBLP dataset by times 5, times 10 and times 15. The results showed that XML-REG has the closest to linear graph compared to other existing approaches. On average, XML-REG showed the best performance in terms of query retrieval time and database storage size.