DTD-Directed Publishing with Attribute Translation Grammars

We present a framework for publishing relational data in XML with respect to a fixed DTD. In data exchange on the Web, XML views of relational data are typically required to conform to a predefined DTD. The presence of recursion in a DTD as well as non-determinism makes it challenging to generate DTD-directed, efficient transformations. Our framework provides a language for defining views that are guaranteed to be DTD-conformant, as well as middleware for evaluating these views. It is based on a novel notion of attribute translation grammars (ATGs). An ATG extends a DTD by associating semantic rules via SQL queries. Directed by the DTD, it extracts data from a relational database, and constructs an XML document. We provide algorithms for efficiently evaluating ATGs, along with methods for statically analyzing them. This yields a systematic and effective approach to publishing data with respect to a predefined DTD.