利用领域知识改进数据仓库中知识发现查询的效率

Improving Query Efficiency of Knowledge Discovery in Data Warehouse by Using Domain Knowledge

随着数据库的规模和存储的数据量越来越大,许多知识发现方面的应用不得不面对大量的数据,这就迫切需要找出降低知识发现查询计算的复杂性的方法。以往的语义查询优化工作都是利用领域知识进行查询优化,主要是靠重写查询语句为一个等价的、高效的查询来降低费用。本文介绍了一种利用三类领域知识进行优化处理、缩小搜索范围、降低查询费用、提高被发现知识的质量的方法。

As the scale and amount of data in database grow,many applications in knowledge discovery have to deal with it. It is necessary to find the way to simplify the query computation for knowledge discovery. All the works of semantic query optimization before are to decrease the cost by rewriting the query sentence to an equivalent and more efficient one. In this paper,a new method is proposed to improve the quality of discovered knowledge and decrease the cost by using three sorts of domain knowledge.