| 关系闭包的计算 |
| |
| 引用本文： | 刘化明.关系闭包的计算[J].厦门大学学报(自然科学版),1989,28(1):25-29. |
| |
| 作者姓名： | 刘化明 |
| |
| 作者单位： | 厦门大学计算机与系统科学系 |
| |
| 摘 要： | 本文涉及演绎数据库递归查询的优化问题,提出算若干计算关系闭包的算法。算法的主要思想是及时地从关系中删去不产生新结果的元组,避免元组间多次重复的连接,提高查询效率。
|
| 关 键 词： | 演绎数据库 递归查询 优化 闭包计算 |
The Efficient Implementation of the Transitive Closure cf Relational Operator |
| |
| Liu Huaming.The Efficient Implementation of the Transitive Closure cf Relational Operator[J].Journal of Xiamen University(Natural Science),1989,28(1):25-29. |
| |
| Authors: | Liu Huaming |
| |
| Institution: | Dept. of Compu. and Sys. Sci. |
| |
| Abstract: | The recent popular argument in deductive database is how tc implement recursive queries efficiently. A recursive qurey may be translated into au extended relational expression, including the closure operation. This paper presents several algorithms to improve the computation of the closure, The main idea is to reduce the cost of each join by deleting those tuples which produce no new result in each iteration from relavant relations. |
| |
| Keywords: | Deductive database Recursive queries Optimization Relational closure |
| 本文献已被 CNKI 维普 等数据库收录！ |
