Temporal aspects of semistructured data

In many applications information about the history of data and their dynamic aspects are just as important as static information. The increasing amount of information accessible through the Web has presented new challenges to academic and industrial research on databases. In this context, data are either structured, when coming from relational or object-oriented databases, or partially or completely unstructured, when they consist of simple collections of text or image files. In the context of semistructured data, models and query languages must be extended in order to consider dynamic aspects. We present a model based on labeled graphs for representing changes in semistructured data and a SQL-like query language for querying it.