UML-based open source data migration tool

Since most of us in IT spend at least part of our time combining and moving data to and from multiple databases, it might be worth taking a look at an open source toolkit called Hydrate that eases the process. From their description:

Hydrate is a Java tool that provides for fast efficient and error-free transformation of data between three different representations: relational databases, objects in an object-oriented programming language and extended markup language (XML).