【摘要】 事务的分布性和事务触发的不可预测性使得分布式主动实时数据库系统中的事务调度变得较为复杂.该文给出了立即和推迟两种模式下执行的被触发事务的截止期确定方法和事务紧急度计算方法,并结合事务的应用语义提出了一种基于多优先级队列的优先级分派策略,有利于主动事务和被触发事务的顺利提交.更多还原

【Abstract】 The distribution of transactions and unpredictability of transaction triggering make the transaction schedule more difficult in distributed active real-time database system (DARTDBS). The methods to determine deadline combining with "data deadline" and to compute criticality by how well the triggered condition is satisfied for the schedule of triggered transaction are discussed under both immediate and deferred coupling modes. Considering the semantics of transactions in DARTDBS, a priority assignment strategy based on multiple priority queues for DARTDBS is also proposed , which is in favor of the commitment of the triggering transaction and triggered transaction.更多还原