Research on Spatial Index Structure of Hybrid Tree In 3D GIS

In spatial database application,to solve the problem that a single special indexing structure constrains retrieval performance with the increment of the amount of data,a hybrid tree special indexing structure is proposed,and so is OR*-tree,which is based on Octree and R*-tree in 3D GIS.It partitions the index space into eight subspaces in each level first,then creates a R*-tree structure for every index space.The experimental procedure of R*-tree and OR*-tree is accomplished,and the experiment has tested the special costs of different lever number OR*-tree and the accessed disk page number in the process of insertion,deletion and searching through uniformity distribution random data.The result of experiment indicates that the method reduces efficiently the operation costs of insertion,deletion and searching for R*-tree.The greater the amount of data is,the better the efficiency is.