Publications

• 2010
  • Härder, T., Mathis, C., Bächle, S., Schmidt, K. and Weiner, A. M.
    Essential Performance Drivers in Native XML DBMSs (keynote paper)
    In: Proc. Current Trends in Theory and Practice of Computer Science (Sofsem 2010), LNCS 5901, Špindlerův Mlýn, Czech Republic, pp. 29-46, Springer, Jan. 2010
• 2009
  • Mathis, C.
    Storing, Indexing, and Querying XML Documents in Native Database Management Systems
    Dissertation, TU Kaiserslautern, Verlag Dr-Hut München, ISBN 978-3-86853-209-8, 365 Pages
  • Mathis, C., Härder, T., Schmidt, K.
    Storing and Indexing XML Documents Upside Down
    In Computer Science - R&D 24(1-2): 51-68 (2009)
  • Mathis, C.
    Query Plans Generated by XTC for the Experiments in the Dissertation of C. Mathis
    Kaiserslautern, April, 2009
  • Weiner, A. M., Mathis, C., Härder, T., Hoppen, C. R. F.
    Now it's Obvious to The Eye—Visually Explaining XQuery Evaluation in a Native XML Database Management System
    In Proc. Datenbanksysteme in Business, Technologie und Web (BTW 2009), 3.-6. März 2009, Münster, Germany.
• 2008
  • Mathis, C., Weiner, A. M., Härder, T., Hoppen, C. R. F.
    XTCcmp: XQuery Compilation on XTC
    In Proc. VLDB 2008 (Demo Track), Auckland, New Zealand.
     
  • Weiner, A. M., Mathis, C., Härder, T.
    Rules for Query Rewrite in Native XML Databases
    In Proc. EDBT Workshops (DataX 2008), Nantes, France
     
  • Härder, T., Bächle, S., Mathis, C.
    Transactional Support in Native XML Databases.
    In Proc. ICEIS (1) 2008: 368-373
     
  • Weiner, A. M., Mathis, C., Härder, T.
    Associativity Rules for Native XML Databases
    Internal Report
     
  • Weiner, A. M., Mathis, C., Härder, T.
    Towards Cost-based Query Optimization in Native XML Database Management Systems
    Accepted for the SYRCoODIS 2008 Sympsium, St. Petersburg, Russia.
     
• 2007
  • Härder T., Mathis, C., Schmidt, K.
    Comparison of Complete and Elementless Native Storage of XML Documents
    In Proc. IDEAS 2007, Banff, Canada
     
  • Mathis, C.
    Extending a Tuple-Based XPath Algebra to Enhance Evaluation Flexibility
    In Informatik - Forschung und Entwicklung 21:3, Springer, May 2007
     
  • Mathis, C.
    Integrating Structural Joins into a Tuple-Based XPath Algebra
    In Proc. BTW, Aachen (Germany), March 2007, pp. 242-261
     
  • Härder, T., Haustein, M. P., Mathis, C., Wagner, M.
    Node Labeling Schemes for Dynamic XML Documents Reconsidered
    Data and Knowledge Engineering 60:1, pp. 126-149, Elsevier, 2007.
     
• 2006
  • Mathis, C., Härder, T., Haustein, M.
    Locking-Aware Path Operators for XML Query Processing
    In Proc. Sigmod, Chicago, Illinois, pp. 467-478, June 2006.
     
  • Mathis, C., Härder, T.
    Twig Query Processing Under Concurrent Updates
    ICDE PhD Workshop, Atlanta (GA), USA, April 2006.
     
  • Mathis, C., Härder, T.
    Hash-Based Structural Join Algorithms
    In Proc. EDBT Workshops, pp. 136-149, Munich, March 2006.
     
• 2005
  • Haustein, M. P., Härder, T., Mathis, C., Wagner, M.
    DeweyIDs - The Key to Fine-Grained Management of XML Documents
    Proc. 20th Brasilian Symposium on Databases, Oct. 2005.
     
  • Mathis, C., Härder, T
    A Query Processing Approach for XML Database Systems
    Proc. 17. Workshop "Grundlagen von Datenbanken", Wörlitz, Sachsen-Anhalt, Mai 2005, pp. 89-93.
     
• 2002
  • Mahnke, W., Mathis, C., Steiert, H.-P.
    Extending an ORDBMS: The StateMachineModule
    Proc. 28th International Conference on Very Large Data Bases (VLDB 2002), Software Demonstration Session, Hong Kong, China, August 2002, pp. 1079-1082.
    

Supervised Documents

• 2008
  • Projektarbeit
    Anwendungsfälle für und Anforderungen an XML-Datenbanksysteme
    Matthias Burkhart
     
  • Diplomarbeit
    Entwicklung von Pfadoperatoren und deren Integration in eine physische XML-Algebra
    Stefan Hühner
     
• 2007
  • Projektarbeit
    Implementierung von indexbasierten Planoperatoren für die Anfrageverarbeitung in nativen XML-Datenbanksystemen
    Stefan Hühner
     
  • Diplomarbeit
    Effiziente und transaktionsgeschützte Speicherung von Dokument-Kollektionen in XML-Datenbanksystemen
    Thomas Sommer
     
  • Diplomarbeit
    Plangenerierung zur Anfrageauswertung in nativen XML-Datenbankverwaltunssystemen
    Andreas M Weiner
     
  • Seminar on Mobile and Context-aware Database Technologies and Applications
    Konsistenzsicherung für mobile Anwendungen
    Volker Hudlet, July 2007
     
• 2006
  • Projektarbeit
    Eine graphische Benutzeroberfläche zur transaktionsgeschützten DOM-Navigation
    Juliane Neumann
     
  • Seminar on Dependable Adaptive Information Systems (DAIS)
    Self-Tuning Databases
    Thomas Sommer, Febuary 2006
     
  • Seminar on Mastering the Information Explosion – Information Integration and Information Quality
    Grundlagen der Informationsintegration
    Paul Schilling, July 2006
     
  • Seminar on Information Retrieval
    Boolesches Retrieval und weitere IR-Modelle
    Markus Messner-Chaney, February 2006
     
  • Seminar on Information Retrieval
    Suchmaschinen im Internet
    Matthias Wolf, February 2006
     
• 2005
  • Seminar on Data Streams
    Operatoren auf Data Streams
    Yi Ou, July 2005
     
  • Seminar on Data Streams
    Verarbeitung von XML-Strömen
    Katharina Bellon, July 2005
     
  • Seminar on Data Streams
    Anfragesprachen
    Sebastian Glöckner, February 2005
     
  • Seminar on Information Retrieval
    Pattern Matching in Texten
    Pascal Hahn, February 2005
     

A Glimpse: The XML Query Graph Model (XQGM)

The XQGM is an extension of the classical Query Graph Model introduced by the relational Starburst system. The model can capture a large fragment of the XQuery language and serves as a basis for rule-based query optimization in XTC. In contrast to algebraic query representations, the graphical XQGM is easy to understand and, therefore, facilitates the development and debugging of XQuery expressions and of our query engine. Details on the XQGM semantics, on XQGM-based query rewriting (especially query unnesting and twig discovery), and on the comprehensive physical XML algebra for the implementation of XQGM-operators in XTC will be published soon.

Screenshots from the XTC Visual Explain Tool

XQGM representation of XMark Query 12 (initial)



 

XQGM representation of XMark Query 12 (after unnesting and twig discovery)



 

Generated Query Evaluation Plan (in XTC's physical XML algebra)