Research And Implementation On Transaction Scheduling For Embedded Active Real-time Database

With the development of computer technology, especially the application of databaseis increasing and wide everyday. Real-time database system as a branch of databasesystem, it applies to the environments where the data is updated constantly and theprocessing of transaction is time-constrained. Transaction scheduling as the core in thereal-time database system, but because of data and transactions have time constraints, sothe study on the scheduling and processing of real-time transaction is very important.This paper get a conclusion that is use the mechanism of the active in the real-timedatabase systems is necessary,and summarizes the transactions and the datacharacteristics in real-time database, the both based on the history of the development ofreal-time database. In real-time database systems, the data changed quickly with thechanges of the state of the external environment, its value is valid only in a certain periodof time, it don’t make sense out of this time frame, so the data must be expressed and storeproperly in the database, which make the transaction that related to it can positioning andaccess quickly. The transaction itself also has time limits, it must fully take into account tothe data’s time constraints, and the other is that in this semantic context of the real-timeapplication, the old models are no longer applicable, must give a more appropriate model.ARTs-EDB is a self-developed and proprietary embedded active real-time databasesystem, combined with the memory database and active database features, which make itfaster and more flexible features, for a variety of application environments.Real-time transaction scheduling in database systems is generally based on priority,based on giving some typical allocation strategy to the priority, then describe how toassign priority and process real-time transaction scheduling in ARTs-EDB system in detail.