摘要
Cbase是南京大学计算机系与南大谷元石油软件研究所有限公司研制的新一代商用关系数据库管理系统。为了提高查询效率,作者开发了Cbase数据库的查询优化器。文章详细论述了Cbase查询优化器中重写模块的设计思想与实现技术,并讨论了基于执行引擎特点引入的一组基于等价谓词的简单语句的重写规则。测试结果表明,所设计的重写器能够显著提高系统的查询效率。
Cbase is a business RDBMS developed by computer department of Nanjing University and Goyeah Ltd.In order to improve query efficiency,the authors have developed Cbase query optimizer.In this paper,the authors first discuss the methods of realizing a query rewrite module on the basis of rewrite technology and then put forward a set of simple rewrite rules based on equivalence predicate.Testing results show that the query performance was obviously improved in contrast with the non-rewriting system.
出处
《计算机工程与应用》
CSCD
北大核心
2002年第22期192-194,238,共4页
Computer Engineering and Applications
基金
南京大学软件新技术国家重点实验室基金资助项目
