XML, the W3C-endorsed and widely used markup language to define semi-structured data, had been proposed in order to represent and exchange data, overcoming the limitations of the un-structured and purely syntactical management of Web data. The usage contexts of XML are highly dynamic and heterogeneous and thus fundamental aspects for an effective XML data management include both the ability to being able to retrieve relevant information even if we are not able to exactly characterize our information request and the full support for changes at the data and metadata level.
In this general context, we contributed to research in: (i) approximate XML querying (where both content and structure constraint specified in the query can be interpreted as soft constraint and results are returned according to a similarity ranking); (ii) XML document and schema co-evolution, i.e., the effects of updates involving document to the associated schema and the other documents in the same data collection, as well as the impact of schema modifications over the documents conforming to it; (iii) efficient processing of XML updates by analysis and simplification of XQuery Pending Update Lists and synthesis of edit-scripts, transforming a source XML document into an updated one, expressed using XQuery Pending Update Lists, key ingredient for any versioning system.