基于查询优化器的分布式空间查询优化方法

为了实现分布式空间数据库之间的互操作，需要对分布式查询进行优化处理，这种查询处理指的是在任何一个数据处理语句中它访问的是各个节点的数据而不是仅仅对发起查询的节点。提出了一种查询优化器的体系结构，针对上述查询最优化做了详细的讨论，着重讨论包含空间选择和连接的复杂空间查询。建立了典型的空间数据库的案例程序，通过分析表明，带有过滤和修正的查询优化器在时间与空间上的效率优势比较明显，获得了具有参考价值的结果。

New distributed spatial query optimization approach by using query analyzer

In order to achieve interoperability between the distributed spatial databases,the user queries optimization of the distributed query processing is an important topic.This kind of distributed query refers to any data processing statement,which access each site of the database rather than the site initiated query requests.Confronted with several kinds of queries optimization problems,a new architecture of query analyzer is presented in this paper.The space selection and connection in complex spatial query is also discussed.In order to demonstrate the effectiveness of this approach,two example experiments are done.The results obtained from performance analysis show that the filters and modification is pivotal factors in queries optimization.This approach has a good effect on time and space cost compared with the traditional solutions.