An XQuery-based version extension of an XML native database

The goal of this paper is to show our experience in the design of an extension to an XML native database in order to add in a native way version features. Due to the lineal nature of time, XML timestamped solutions for the management of XML versions have difficulty in supporting non-linear versioning, and their implementations are scarce and not very portable. From our technique described in [6, 7], which allows us to manage branch versioning, we have developed our versioning system focusing on its high portability and platform independence properties. To achieve this, our versioning system is based exclusively on XML technology. The system is composed by XQuery modules, so that this allows its use not only in an XQuery engine but also in an XQuery-support XML native database. To test it, the modules have been integrated in an eXist XML native database, an XML difference tool is used to observe the changes made between versions, and the eXist web interface has been extended to make the management of XML versions easier.