This paper summarizes the situation about using XLink for connecting XML instances. We discuss applications where XLink functionality can be useful, and derive requirements how the basic XLink technology should be supported in these scenarios. We compare several proposals dealing with interlinked XML data with our dbxlink approach which is a minimal extension to XLink and XPath, and we show how...

We provide a sound, complete and terminating tableau procedure to check satisfiability of downward XPath= formulas enriched with nominals and satisfaction operators. The calculus is inspired by ideas introduced to ensure termination of tableau calculi for certain Hybrid Logics. We prove that even though we increased the expressive power of XPath by introducing hybrid operators, the satisfiabili...

In this paper we investigate the feasibility and efficiency of mapping XML data and access control policies onto relational and native XML databases for storage and querying. We developed a re-annotation algorithm that computes the XPath query which designates the XML nodes to be re-annotated when an update operation occurs. The algorithm uses XPath static analysis and our experimental results ...

The XPath query language offers a standard for information extraction from HTML documents. Therefore, the DOM tree representation is typically used, which models the hierarchical structure of the document. One of the key aspects of HTML is the separation of data and the structure that is used to represent it. A consequence thereof is that data extraction algorithms usually fail to identify data...

Whenever queries have to be evaluated on XML data streams or when the memory that is available to evaluate the XML data is relatively small compared to the document DOM based approaches that have to load and store large parts of the document in main memory will fail. In comparison, we present an approach to evaluate XPath queries on SAX streams that supports all axes of core XPath, including th...

Whenever multiple users modify XML documents concurrently, access control and synchronization of read and update operations are required. We suggest to define access rights and locks at the level of node names that are defined in the DTD of the XML document. This allows us to normalize (a subset of) XPath expressions, used e.g. in queries, such that access control and synchronization can be per...

The problem of finding subclasses of XPath queries and document type definitions (DTDs) for which containment can be tested efficiently has been much studied. Along the way, a number of constraints inferred from DTDs have been used to characterise containment in terms of the chase procedure. However, previous attempts have resulted in procedures that are non-terminating for cyclic DTDs, even wh...