THE CORRECTNESS OF REAL-TIME TRANSACTIONS AND ITS IMPLEMENTATION

The transactions in real-time database systems can have timing constraints（typically the deadlines） and the transactions which exceeds their deadlines can cause catastrophic effects to the system. The execution of transactions must satisfy not only the integrity and consistency of database but also the timing correctness and structure correctness among transactions. The traditional transaction processing methods only consider the transaction behavior of data accessing and is helpless to the implementation of transaction timing correctness and structure correctness. The correctness of real-time transactions is discussed in detail and it is found that the transaction correctness includes the result correctness, time correctness, structural correctness and behavioral correctness. In literatures, different algorithms and strategies are often applied to implement the different correctness. Also given is a uniform graphic algorithm to achieve the real-time transaction correctness.