A scheme to specify and implement ad-hoc recovery in workflow systems

  • Jian Tang
  • San -Yih Hwang
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1377)


Pre-defining a business process can substantially simplify the process design and the implementation of run time support. However, requiring that all the instances of the business process follow a fixed pattern (even if conditions are allowed) does not offer users sufficient flexibility to make changes to the process structures. These changes may be necessary due to the occurrence of exceptions, or other ad-hoc events. Some exceptions/events may be predictable in advance, and therefore can be incorporated into the process definition. However, not all exception/events can be predicted at the process definition time. When this happens, no corresponding exception-specific provision can be incorporated. The design and implementation of the system support for unpredictable exception/event handling is therefore a more complicated issue. In this paper, we study a special case of changing the structure of a business process in the context of unpredictable exception/event, namely, redirecting the control flow at run time in an ad-hoc manner. This phenomenon is termed ad-hoc recovery. We concentrate on two aspects in supporting ad-hoc recovery, the kind of interface that should be used and the increased functionality that must be built into the workflow database. For the latter, we also suggest implementation strategies to maximize the performance.


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  1. 1.
    P.C. Attie, M.P. Singh, A. Sheth, M. Rusinkiewicz: Specifying and Enforcing Intertask Dependencies. Proc. of 19th VLDB Conference, VLDB Endowment. (1993) 134–144.Google Scholar
  2. 2.
    P. Barthelmess, J. Wainer: Workflow Systems: a few Definitions and a few Suggestions. Proc. of ACM Conference on Organizational Computing Systems. (1995) 138–147.Google Scholar
  3. 3.
    R. Blumenthal, G. Nutt: Supporting Unstructured Workflow Activities in the Bramble ICN System. Proc. of ACM Conference on Organizational Computing Systems. (1995) 130–137.Google Scholar
  4. 4.
    P.K. Chrysantis, K. Ramamritham: Synthesis of Extended Transaction Models Using ACTA. ACM Transactions on Database systems. 19 (1994) 450–491.CrossRefGoogle Scholar
  5. 5.
    U.Dayal, M. Hsu, R. Ladin: A Transactional Model for Long-Running Activities. Proc. of 17th VLDB Conference, VLDB Endowment. (1991) 113–122.Google Scholar
  6. 6.
    C. Ellis, G. Rozeberg: Dynamic Change Within Workflow Systems. Proc. of ACM Conference on Organizational Computing Systems. (1995) 10–21.Google Scholar
  7. 7.
    A. Elmagarmid: (ed.), Database Transaction Models for Advanced Applications. Morgan-Kaufman Publishers, USA. (1992).Google Scholar
  8. 8.
    A. Elmagarmid, Y. Leu, W. Litwin, M. Rusinkiewicz: A Multidatabase Transaction Model for Interbase. Proc. of the 16th VLDB Conf. (1990).Google Scholar
  9. 9.
    D. Georgakopoulos, M.F. Hornik: Framework for Enforceable Specification of Ex-tented Transaction Models and Transactional Workflows. Intl. Journal of Intelligent and Cooperative Information Systems. (1994).Google Scholar
  10. 10.
    D. Georgakopoulos, M. Hornik, A. Sheth: An Overview of Workflow Management: from Process Modeling to Workflow Automaton Infrastructure. Dist. and Parll. Databases: An International Journal. 3 (1994) 119–153.CrossRefGoogle Scholar
  11. 11.
    G. Kappel, P. Lang, S. Rausch-Schott, W. Retschitzegger: Workflow Management Based on Objects, Rules, and Roles. Bulletin of the Technical Committee on Data Engg. 18 (1995) 11–18.Google Scholar
  12. 12.
    N. Krishnakumar, A. Sheth: Managing Heterogeneous Multi-system Tasks to Support Enterprise-wide Operations. Dist. and Parll. Databases: An International Journal. 3 (1995) 1–33.Google Scholar
  13. 13.
    D. McCarthy, S. Sarin: Workflow and Transactions in InConcert. Bulletin of the Technical Committee on Data Engg. 16 (1993). 53–56.Google Scholar
  14. 14.
    M. Singh: Synthesizing Distributed Constrained Events from Transactional Workflow Specifications. Proc. of 12th Intl. Conf. on Data Engg. (1996) 616–623.Google Scholar
  15. 15.
    B. Salzberg, D. Tombroff: DSDT: Durable Scripts Containing Database Transactions. Proc. of 12th Intl. Conf. on Data Engg. (1996) 624–633.Google Scholar
  16. 16.
    Workflow Management Coalition: Workflow Reference Model. (1996).Google Scholar
  17. 17.
    J. Tang, S. Hwang: Coping with Uncertainties in Workflow Applications. Proc. of Intl. Conf. on Information and Knowledge Management. (1996).Google Scholar
  18. 18.
    J. Tang, J. Veijalainen: Enforcing Inter-Task Dependencies in Transactional workflows. Proc of 3rd Intl. Conf. on Cooperative Information Systems. (1995).Google Scholar
  19. 19.
    J. Wainer, M. Weske, G. Vossen, C. Medeiros: Scientific Workflow Systems. Proc. of the NSF Workshop on Workflow and Process Automation in Information Systems. (1996).Google Scholar
  20. 20.
    WorkGroup 1/B: Workflow Management Coalition Interface 1: Process Definition Interchange. The Workflow Management Coalition. (1996).Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Jian Tang
    • 1
  • San -Yih Hwang
    • 2
  1. 1.Department of Computer ScienceMemorial University of Newfoundland St.John'sNewfoundlandCanada
  2. 2.Department of Information ManagementNational Sun Yat-Sen UniversityKaohsiungTaiwan

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