An Improved Dimension Hierarchy Aggregate Cube Storage Structure for Data Warehouses

In this paper it is proposed to create high performance DHAC (dimension hierarchy aggregate cube) with the dimension hierarchy aggregate technique on the cube. By using the dimension hierarchy of the dimension hierarchy aggregate tree, the DHAC can optimize the query efficiency and the update efficiency, and the cube semantic operation such as roll up and drill down can also be supported. The DHAC can incrementally update all the affected ancestor notes while updating the data cell by insertion and deletion in it. The DHAC can also incrementally update without being recreated while being added new dimension data in it. As a result, this algorithm can greatly reduce the update time. The algorithms of DHAC are compared with all the existing ones such as SDDC(space-efficient dynamic data cube) by more experiment. The analytical and experimental results show that the algorithms of DHAC proposed are more efficient than other existing ones.