Towards Cost-Based Query Optimization in Native XML Database Management Systems
In the last few years, XML became a de-facto standard for the exchange of structured and semi-structured data. The database research community took this development into account by proposing native XML database management systems for efficient and transactional management of XML documents. One of the most important factors for success of such systems is a powerful query optimizer. Many researchers proposed sophisticated structural join and holistic twig Join algorithms as well as several index structures supporting the evaluation of twig query patterns.