SPINE：一个轻型永久对象管理器

在信息系统中，应用程序是基于对象模型的，但企业数据主要还是存储在关系型数据库中。永久对象管理层搭起了一个沟通对象模型和关系模型的桥梁，简化了应用程序的开发。SPINE是我们开发的一个轻型的永久对象管理构架，它允许系统中同时存在一个对象的多个拷贝，并通过版本机制来解决访问冲突；其次，它引入了三层对象设计模式，使系统更加紧凑；它还通过PROXY设计模式实现了关联对象的延迟装载，从而提高了系统性能。

SPINE :A Lightweight Persistent Object Manager

Applications used in e-busiiness of enterprise information systems are based on the object model,but the data is usually managed by relational databases. A persistent object access layer makes up the bridge between the ap- plications based on the object model and databases based on the relational model. SPINE,a lightweight persistent ob- ject manager,allows applications to create multiple copies of a object at a time and resolve the access conflicats with the version mechanism. It introduces the 3-layer pattern to make the design of the system more compact. Moreover, the use of the prox to delay the loading of the associated objects improves the system performance dramatically.