Research of Query Optimization Based on Genetic Algorithm in Distributed Database
An Gong · Journal of Chinese Computer Systems · 2009
A new cost model of distributed database query based on the study of availability semi-joins is put forward in this paper,which can describe the cost of distributed database query precisely by including selection of relation copies,query order of multi-join,determination of performance sites,transaction of data and cost of local computation,and the cost model is analyzed,designed and realized by the constructive global data dictionary and dynamic state dictionary.The genetic algorithm that is used to resolve the query optimization problem based on the new cost model is given,the experiment results indicate that the algorithm is effective.