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Abstract Concurrency control in database management systems has been a major focus of research in the past years. Concurrency control is applied to permit concurrent transaction-processing while still assuring database consistency. The basic approaches to concurrency control are Two-Phase Locking (2PL). Timestamp Ordering (T/O). and Certification (or Commit-Time Validation (CTV». Numerous variations of these algorithms have been proposed and algorithm correctness work has achieved a degree of mathematical maturity. Due to the complexity of the issues affecting the performance of concurrency control algorithms. simulation is often resorted to as the means for performance evaluation. Several attempts. however. have been made to make use of analytical methods for this purpose. Most existing performance studies of concurrency control algorithms use different approaches and make assumptions. However. a successful attempt a unified approach has been carried out by Y.C. Tay’s analytic approach is based on a flow diagram a set of equations derived using only the steady |