基于XML的分布式数据库递归查询优化

One of Distributed Recursive Queries Based on XML

在分布式数据库中,查询处理的主要矛盾在于由数据的分布与冗余所引起的站点间的数据传递及通信的开销。因此,分布式数据库的查询优化显得尤为重要。本文通过应用XML技术,对用户提交的递归查询任务进行分析,得出一个最小的查询视图,然后对各分布式数据库进行查询,并把查询所得到的结果反馈给用户,从而实现对分布式数据库查询效率的提高。

In the distributed database, owing to the distributed and redundancy of data, data transmission and communicating costs between sites in deal with inquiry become the main contradiction in the inquiry about distributed database. Therefore, the optimized inquiry method based on distributed database, becomes one of the cores of the database query theories. This paper uses XML to analyze the user＇s recursive query assignments to obtain the smallest query view, then query to each distributed database, and return the results of the query to the user to realize the effective query to the distributed database.