We study the satisfiability problem associated with XPath in the presence of DTDs. This is
the problem of determining, given a query p in an XPath fragment and a DTD D, whether or …

These are introductory lectures to some aspects of the physics of strongly correlated electron
systems. I first explain the main reasons for strong correlations in several classes of …

The problem of exchanging data between different databases with different schemas is an
area of immense importance. Consequently data exchange has been one of the most active …

Data exchange is the problem of finding an instance of a target schema, given an instance of
a source schema and a specification of the relationship between the source and the target …

Consider an XML publish-subscribe scenario with hundreds of subscribers and tens of
thousands of XML documents to be delivered per day. Subscribers specify the documents in …

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 …

We investigate the problem of learning XML queries, path queries and twig queries, from
examples given by the user. A learning algorithm takes on the input a set of XML documents …

The performance of XML database queries can be greatly enhanced by rewriting them using
materialized views. We study the problem of rewriting a query using materialized views …

Relational schema map**s have been extensively studied in connection with data
integration and exchange problems, but map**s between XML schemas have not …

The efficient processing of XQuery still poses significant challenges. A particularly effective
technique to improve XQuery processing performance consists of using materialized views …