Interactive Schema Translation with Instance-Level Mappings

We demonstrate a prototype that translates schemas from a source metamodel (e.g., OO, relational, XML) to a target metamodel. The prototype is integrated with Microsoft Visual Studio 2005 to generate relational schemas from an object-oriented design. It has four novel features. First, it produces instance mappings to round-trip the data between the source schema and the generated target schema. It compiles the instance mappings into SQL views to reassemble the objects stored in relational tables. Second, it offers interactive editing, i.e., incremental modifications of the source schema yield incremental modifications of the target schema. Third, it incorporates a novel mechanism for mapping inheritance hierarchies to relations, which supports all known strategies and their combinations. Fourth, it is integrated with a commercial product featuring a high-quality user interface. The schema translation process is driven by high-level rules that eliminate constructs that are absent from the target metamodel.