A method is provided for defining a metadata schema to facilitate passing data between an XML document and a hierarchical database. The invention includes a database accessor, a document accessor, and an association module. The database accessor accesses a database schema indicative of database field names and a hierarchical structure for a hierarchical database. The document accessor accesses a document schema that defines the hierarchical structure, content data syntax, and semantics of valid, well-formed, XML documents that can be passed into and out of the hierarchical database. The document schema also includes at least one XML element name that maps to a corresponding database field name in the database schema. The association module associates the database schema and the document schema to provide a metadata schema that enables data to be passed between an XML document and the hierarchical database.