Selectively Storing XML Data in Relations

This paper presents a new framework for users to select relevant data from an xml document and store it in an existing relational database, as opposed to previous approaches that shred the entire xml document into a newly created database of a newly designed schema. The framework is based on a notion of xml2db mappings. An xml2db mapping extends a (possibly recursive) dtd by associating element types with semantic attributes and rules. It extracts either part or all of the data from an xml document, and generates sql updates to increment an existing database using the xml data. We also provide an efficient technique to evaluate xml2db mappings in parallel with sax parsing. These yield a systematic method to store xml data selectively in an existing database.