APPARATUS AND METHOD FOR RANGE QUERYCOMPUTING THE SELECTIVITY OF A RAGNE QUERY FOR MULTIDIMENSIONAL DATA

摘要

PURPOSE: A device for calculating the selectivity of an area query related to multidimensional data and a method thereof are provided to increase the accuracy of area query selectivity estimation by generating a multidimensional histogram and space division trees. CONSTITUTION: A tree generating unit(101) divides a data space according to the skew sum total of areas of the data space and generates a space division tree related to the data space. A histogram generating unit(103) generates a histogram related to the data space based on the space division tree. The tree generating unit receives an integer value more than 3 as tree generation information related to the generation of the space division tree. The tree generating unit divides the data space based on minimum skew space division. [Reference numerals] (101) Tree generating unit; (102) Minimum cover obtaining unit; (103) Histogram generating unit; (104) Area query processing unit