An Effective Drill-down Paths Pruning Method in OLAP
OLAP分析中一种有效的下钻路径裁减技术

The OLAP provides a convenient way for data analysis.But the complexity of multi-dimensional data structure affects the efficiency of OLAP, because there are too many drill-down paths to be chosen from when analysis.How to prune the complex and tedious analysis paths is one of the major issues in this research field.While most methods in the literature are associated to some specific analysis tasks, so they cannot get reasonable effect.In this paper, we proposed a new method that is irrelevant to analysis task.In order to simplify the OLAP analysis process, we prune the invalid drill-down operations.The vetorial angle method is employed to evaluate the validness of every drill-down operation.We give the corresponding path pruning algorithm, and it is effective that it takes the fact table as the input in only one pass scanning.The experiments show that our method is feasible, effective, sparsity-proof and skewness-proof.