Optimal Query Mapping in Mobile OLAP

Query mapping to aggregation lattices is used in order to exploit sub-cube dependencies in multidimensional databases. It is employed in mobile OLAP dissemination systems, in order to reduce the number of handled data items and thus optimize their scheduling and dissemination process. This paper analyzes the impact of choosing between mapping to the data cube lattice or alternatively to the respective hierarchical data cube lattice. We analyze the involved tradeoffs and identify the exploitation degree of sub-cube derivability as the deciding factor. We therefore introduce an analytical framework which computes derivability related probabilities and thus facilitates the quantification of this degree. The information provided by the framework is consistent with experimental results of state of the art mobile OLAP dissemination systems.