Relational universal index structure for evaluating XML twig queries

Numerous approaches to storing XML data in relational databases have been proposed that take advantage of the maturity of relational database management systems. Index structures to support these approaches have been developed to speed-up XML query processing. Typical drawbacks of these approaches include the lack of support for twig queries and the large storage requirements for the index structures. In this paper we propose a novel index structure that is compact and effectively supports processing of XML twig queries. Experimental results show that our approach achieves lower response time than similar approaches while using less space to store the XML data.