Department of Computer Engineering, Sari Branch, Islamic Azad University, Sari, Iran
Department of Computer Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran
The large number of applications manages time varying data. Existing database technology seldom supports temporal database, TDB, according to time aspects. These intrinsic temporal database applications rely on such database which stores and retrieves time referenced data. Moreover, applications need to be managed on common data items access simultaneously and to be precluded from inconsistency as soon as possible which is the main task of concurrency controller or CC in short. The method used by CC in typical DB differs from its attitude with TDB. The variety algorithms were proposed regarding to TDB properties by reduction of granule size and decreasing the rate of conflicts to satisfy good performance, but none of them has achieved robust results. There are two categories of CC such as pessimistic and optimistic. In this paper new approach, with considering the TDB aspects, based on optimistic method has been suggested. It reclines the size of granule as data item appropriately and recognizes the conflicts swiftly. Consequently, we compare our proposed algorithm with pervasive 2PL-pessimistic approach. The outcome shows that new proposed algorithm has high degree of trade off with satisfying near conflict time detection and high rate of parallelism metrics.