Current Research on concurrency ControlRealtime Databases

1
Current Research on concurrency ControlReal-time
Databases

• Special Requirements
• Methods
• Lee. J. 1994
• Huang, J. et al. 1991
• Future Work
• Evaluation of the performance
• Shared data among transactions
• Distributed real-time system

2
Current Research on Concurrency
ControlDistributed Databases

• Special Requirements
• Methods
• THOMASIAN, A. et al. 1990
• CAREY, M. J. et al. 1991
• Future Work
• Wide-area (WAN) distributed database system
• Heterogeneous distributed database systems

3
Current Research on Concurrency
ControlMultidatabases

• Special Requirements
• Distributed heterogeneous DBMS
• Local transactions are run under the control of a
  local DBMS
• A multidatabase system is provided to run global
  transactions.
• A hierarchical architecture for multidatabase
  systems
• Mehrotra et al. 1997

4
Current Research on Recovery

• Research Trend
• Not much has been done
• Sophisticated algorithms
• Lack of formal form
• Formalization using Gurevich Abstract State
  Machine (ASM) Y. Gurevich et al. 1995
• Describe the ASM at conceptual level
• Refine on each state
• Further refinement

5
Concurrency Control and Recovery

• Concurrency control and recovery
• Treated separately
• Indeed interact in subtle way
• Unified theory
• Correctness criterions
• Expanded serializability
• Apply serializability arguments

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References

• A. Thomasian. Concurrency control Methods,
  performance, and analysis. ACM Computing Surveys
  30,1 (March 1998), pp. 70-119.
• Lee, J. 1994. Concurrency control algorithms for
  real-time database systems. PhD Thesis,
  Department of Computer Science, University of
  Virginia.
• HUANG, J., STANKOVIC, J. A., RAMAMITHRAM, K., AND
  TOWSLEY, D. 1991. Experimental evaluation of
  real-time optimistic concurrency control schemes.
  In Proceedings of the Seventeenth International
  Conference on Very Large Data Bases (Barcelona,
  Sept.), 3546.
• THOMASIAN, A. AND RAHM, E. 1990. A new
  distributed optimistic concurrency control method
  and a comparison of its performance with
  two-phase locking. In Proceedings of 1990
  International Conference on Distributed Computing
  Systems (Paris, May), 294301.
• CAREY, M. J. AND LIVNY, M. 1991. Conflict
  detection tradeoffs for replicated data. ACM
  Trans. Database Syst. 16, 4 (Dec.), 703746.
• MEHROTRA, S., KORTH, H. F., AND SILBERSCHATZ, A.
  1997. Concurrency control in hierarchical
  multidatabase systems. Int. J. Very Large Data
  Bases 6, 157172.
• Y. Gurevich, N. Soparkar, and C. Wallace.
  Formalizing database recovery. In COMAD, 1995.
• H.-J. Schek, G. Weikum, and H. Ye. Towards a
  Unified Theory of Concurrency Control and
  Recovery. In 12th ACM SIGACT--SIGMOD--SIGART
  Symposium on Principles of Database Systems
  (PODS), Washington, DC, May