Abstract
As the amount of XML documents on the Web is constantly increasing, and since their contents can change over time, updating these documents with concurrency control becomes an interesting issue. The main problem is to detect conflicts between transactions. In this paper, we present an approach to detect conflicts between transactions. Our approach is based on path expressions associated with operations. This make our approach scalable in the majority of cases since it is independent from the database size as well as from the number of modified fragments. We give here the global architecture of our concurrency control mechanism in which our algorithm, to detect conflicts, is improved. Finally, we describe an experimental evaluation of our approach.