基于类网络的OODB事务处理模型

A Class Network-Based Transa(?)ion Model for OODBs

1、引言当前,OODB 已成为数据库领域的热门话题,并从实验上和理论上获得了高度重视。但是,关于这种系统的定义还存在着不少争议,有三点可以概括 OODB 初期研究阶段的状况:(1)缺少形式化的定义,(2)没有共同的数据模型,(3)大量的实验性活动。这些问题同样存在于OODB 事务处理的研究之中。事务处理机制是数据库系统中广泛采用的控制程序并发执行的手段,通常,事务被看作数据库并发和恢复的基本单位。

In the database field,transaction processing has long been recognized com- monly as not only an advanced,but also a difficult topic.The transaction models for existing object-oriented databases(OODBs)are almost all extensions to,or bo- rrowed from traditional transaction models.They captures only a few characteris- tics of OODBs.Our Contributions in this paper are three aspects.First,we take a new look at the relationship between database and its transaction processihg.A database is viewed as an object's structure,and its transaction processing system as the method of this object.Second,we present a transaction model for an OO- DB——GOODbase,which is being developed by us on SUN workstation.The idea of this model can be applied generally to other OODBs.Third,we distinguish two kinds of concurrency in our model,namely,entra-and intra-object paralle- lisms.Some implementation issues are also considerated here.