连续不确定XML数据索引技术研究

ON INDEXING TECHNOLOGY OF CONTINUOUS UNCERTAIN XML DATA

针对连续不确定XML数据的概率阈值查询,提出CPTI(Continuous Probabilistic Threshold Index)索引技术,包括CPTI结构索引和CPTI值索引。CPTI结构索引扩展了结构索引F-index支持连续不确定XML数据,通过CPTI结构索引查询twig小枝,并确定小枝的路径概率;CPTI值索引是一个二维表,记录cont类节点的概率信息,通过CPTI值索引过滤与查询无关的元素以减少查询中需要处理的元素数目。实验表明,此索引技术可极大地提高查询处理的性能。

In light of the probabilistic threshold query of continuous uncertain XML data, we propose indexing technology of continuous probabilistic threshold index （ CPTI）, including CPTI structure indexing and CPTI value indexing. CPTI structure indexing extends the structure index F-index to support continuous probabilistic XML data; through CPTI structure indexing it is able to query twig and to determine the path probability of twig; CPTI value indexing is a two-dimensional table recoding the probability information of the nodes of cont class, through CPTI value indexing to filter the elements which is nothing to do with the query, it is able to reduce the number of element to be processed in query. Experiment shows that this index technology can greatly improve the performance of query processing.