So most research of distributed query optimization aim at reducing communication cost 所以大多数研究分布式查询优化以减少通讯开销为目标。
In distributed query optimization , this paper aims at how to reduce communication cost , adopting semi - join program 对于用传统的sdd - 1算法来寻找全归约程序进行改进。
Distributed query optimization research is under way in universities , research laboratories and similar establishments 分布式查询优化的研究领域是分布式数据库中的研究热点。
The distributed query optimization problem is the key point in distributed database systems , and it is an np hard one 既有理论上的问题,也有实际应用中的问题。这些问题在当前显得尤为重要。
By keeping the above facts , i delved deeply in distributed query optimization algorithms , made some notable achievement . the paper focuses primarily on distributed query optimization 我正是在前人研究的问题基础上,对分布式查询优化方面的算法进行了深入的研究,取得了显著效果。