ORDBMS的新特性及其对查询优化的影响  

New Characteristics of the ORDBMS and Their Effect on Query Optimization

作　　者：殷贤亮[1] 吴海[1] 

机构地区：[1]华中科技大学计算机科学与技术学院

出　　处：《华中科技大学学报（自然科学版）》2001年第12期92-94,共3页Journal of Huazhong University of Science and Technology(Natural Science Edition)

摘　　要：讨论了ORDBMS的一些新特性 ,ORDBMS应该支持用户自定义的数据类型和函数 ;存储机制能够支持复杂对象或大对象 ;其索引结构必须是类属的 ;它还必须支持数据和函数的继承 .讨论了这些特性对查询优化策略的影响 ,指出传统DBMS的优化策略将不能适应这些新特性 。New characteristics of the ORDBMS are introduced, the ORDBMS should support the types of data and functions defined by users; complex objects and big objects can be stored under their mechanism of storage; the structure of index of the ORDBMS must be classified by classes; the ORDBMS must support the inheritance of data and functions. This paper discusses the effect of these characteristics on the optimization of query policy, points out that the traditional query policy should not be fit for these new characteristics and puts forward the model of query optimization based on cost.

关 键 词：对象关系数据库系统 查询策略 查询优化 成本优化 ORDBMS 存储机制 索引结构 

分 类 号：TP311.132[自动化与计算机技术—计算机软件与理论]