An Efficient Detection of Conflicting Updates in Valid XML

As soon as many users and applications work concurrently on valid XML documents, transaction management for valid XML becomes an important issue. A fundamental problem is the detection of conflicts between operations. The detection of conflicts between operations is very interesting in query optimization for a query compiler and concurrency for a transaction manager. In this paper, we studies the problem of detecting conflicts among XML update operations in the case that input documents are typed by an XML schema (DTD or XML schema). We formalize READ-UPDATE and UPDATE-UPDATE conflicts in valid XML documents, and propose efficient algorithms to detect such conflicts when the update operations are specified using XPath expressions.