LinXIS: Linked XML Information Sources (2001-2007)

The project investigated the database aspects of linked XML instances.

• Data Modeling
• Querying and Evaluation
• Applications

Publications

• Draft: Considerations on Linked XML Document Networks in the Web, Wolfgang May; 2002.
• Evaluation aspects have been presented in Querying Linked XML Document Networks in the Web, Wolfgang May; 11th International World Wide Web Conference (WWW 2002), May, 7-11, 2002, Honolulu, Hawaii.
• A potential application area has been sketched in Linking the Semantic Web with Existing Sources, Wolfgang May, Workshop on Web Semantics (WebS'02), Sept. 3, 2002, Aix-en-Provence, France. In Proc. DEXA 02 Workshops, IEEE Computer Society.
• A Logical, Transparent Model for Querying Linked XML Documents, Wolfgang May, Dimitrio Malheiro; GI-Fachtagung Datenbanksysteme für Business, Technologie und Web , 2003.
• Handling Interlinked XML Instances on the Web, Erik Behrends, Oliver Fritzen, Wolfgang May, 10th. Intl. Conference on Extending Database Technology (EDBT'06) , 2006.
• Querying along XLinks in XPath/XQuery: Situation, Applications, Perspectives, Erik Behrends, Oliver Fritzen, Wolfgang May, 11th International Workshop on Foundations of Models and Languages for Data and Objects (FMLDO): QLQP-2006 "Query Languages and Query Processing" , 2006.
• Integrating and Querying Distributed XML Data via XLink. Erik Behrends, Oliver Fritzen, Wolfgang May; Information Systems 33(6), pp. 508-566, 2008.

PhD Theses from this project

• Erik Behrends: Evaluation of Queries on Linked Distributed XML Data, Dec. 2006.
• Oliver Fritzen: Modeling and Querying of Distributed XML Data in Presence of 3rd Party Links, Jan. 2008.

The approach has been implemented as an extension of the native XML database system eXist. A demo with some example queries has been available, but went out of service in late 2008.
The project used a distributed XML version of the Mondial database which is still available (data frozen in 2006).

The project has been supported in 2003-2006 by the Deutsche Forschungsgemeinschaft (DFG).

Earlier prototypes

As a first step, an XSLT script that materializes the logical data model has been written for validating and illustrating the approach. As a second step, a prototype based on the LoPiX system for evaluating queries against distributed, linked sources has been implemented (2003).