基于小生境遗传算法的SDD-1分布式查询优化算法

SDD-1 Distributed Query Optimization Algorithm Based on Niche Genetic Algorithm

SDD-1算法是一种分布式数据库的查询优化算法,遗传算法已经在许多领域得到了成功的应用。针对基于遗传算法的SDD-1算法中,遗传算法存在"早熟收敛"的问题,提出一种基于小生境遗传算法的SDD-1分布式查询优化算法,该算法能在尽可能短的时间内求解通信费用最小的查询计划。实验结果表明,该算法比单独使用SDD-1算法、基于遗传算法的SDD-1算法均有更优的性能。

SDD-1algorithm is a distributed query optimization algorithm,the genetic algorithm has been successfully applied in many fields.In the SDD-1algorithm based on genetic algorithm,genetic algorithm has a problem of＂premature convergence＂.To solve this problem,SDD-1distributed query optimization algorithm based on niche genetic algorithm is proposed in this research.This algorithm can solve the query plan of minimum communication cost in possible time.Experimental results show that this algorithm has a better performance than SDD-1algorithm and SDD-1algorithm based on genetic algorithm.