This survey gives an overview of formal results on the XML query language XPath. We
identify several important fragments of XPath, focusing on subsets of XPath 1.0. We then …

Two highly efficient algorithms are known for optimally ordering joins while avoiding cross
products: DPccp, which is based on dynamic programming, and Top-Down Partition Search …

Since the boom in new proposals on techniques for efficient querying of XML data is now
over and the research world has shifted its attention toward new types of data formats, we …

Dataspace management has been recently identified as a new agenda for information
management [17, 22] and information integration [23]. In sharp contrast to standard …

With the rapid emergence of XML as a data exchange standard over the Web, storing and
querying XML data have become critical issues. The two main approaches to storing XML …

As XQuery nears standardization, more sophisticated XQuery applications are emerging,
which often exploit the entire language and are applied to non-trivial XML sources. We …

To address the needs of data intensive XML applications, a number of efficient tree pattern
algorithms have been proposed. Still, most XQuery compilers do not support those …

Experience with relational systems has shown that distribution is an effective way of
improving the scalability of query evaluation. In this paper, we show how distributed query …

Queries formulated in a nested way are very common in XQuery. Unfortunately, their
evaluation is usually very inefficient when done in a straightforward fashion. We present a …

Query processing performance in XML databases can be greatly enhanced by the usage of
materialized views whose content has been stored in the database. This requires a method …