数据库系统中并发事务死锁的解除与避免

Undoing and Avoiding the Deadlock of the Concurrent Transaction in Database System

摘要: 本文利用Ｐｅｔｒｉ网作为工具，从提高事务进程并行性出发，建立数据库系统的并发事务进程竞争数据资源的模型，并由此推导出死锁和临界死锁的充分必要条件及提出相应的避免死锁的控制机制。该控制机制是通过如何对关键的空闲数据资源进行控制分配来实现避免死锁。

Abstract: By means of Petri net and from the point of improving the transaction process concurrency, this paper establishes a competitive data resource model for the concurrent transaction process of the database system.The corresponding deadlock-avoiding control mechanism can avoid the deadlock by controlled allocation of the keyspare data resources.