Motivated by reasoning tasks for XML languages, the satisfiability problem of logics on data
trees is investigated. The nodes of a data tree have a label from a finite set and a data value …

The Internet and World Wide Web have revolutionized access to information. Users now
store information across multiple platforms from personal computers to smartphones and …

The evolution of the web has outpaced itself: A growing wealth of information and
increasingly sophisticated interfaces necessitate automated processing, yet existing …

The goal of this paper is to give an overview of the basics of the theory of RDF databases.
We provide a formal definition of RDF that includes the features that distinguish this model …

Diagrams are essential tools for problem-solving and communication as they externalize
conceptual structures using spatial relationships. But when picking a diagramming …

The Grammar of Graphics (GoG) has become a popular format for specifying visualizations
because it unifies different chart types into a consistent, modular, and customizable …

A data tree is a finite tree whose every node carries a label from a finite alphabet and a
datum from some infinite domain. We introduce a new model of automata over unranked …

Summary Extensible Markup Language (XML) documents consist of text data plus structured
data (markup). XPath allows to query both text and structure. Evaluating such hybrid queries …

We investigate efficient view maintenance for MSO-definable queries over trees or, more
precisely, efficient enumeration of answers to MSO-definable queries over words and trees …

This is the first book that provides a solid theoretical account of the foundation of the popular
data format XML. Part I establishes basic concepts, starting with schemas, tree automata and …