This paper proposes a number of type-system and language extensions to natively support relational and hierarchical data within a statically typed object-oriented setting. In our approach SQL tables and XML documents become first class citizens that benefit from the full range of features available in a modern programming language like C# or Java. This allows objects, tables and documents to be constructed, loaded, passed, transformed, updated, and queried in a unified and type-safe manner.

This article describes how Perl can be used to transfer data between XML and relational databases, and how XML can bridge two disparate databases. MySQL is used as an example database.