Existing datacube precompuatation schemes materialize selected datacube tuples on disk, choosing the most beneficial cuboids (i.e., combinations of dimensions) to materialize given a space limit. However, in the context of a data-warehouse receiving frequent “append” updates to the database, the cost of keeping these disk-resident cuboids up-to-date can be high. In this paper, we propose a main memory based framework which provides rapid response to queries and requires considerably less maintenance cost than a disk based scheme in an append-only environment. For a given datacube query, we first look among a set of previously materialized tuples for a direct answer. If not found, we use a hash based scheme reminiscent of partial match retrieval to rapidly compute the answer to the query from the finest-level data stored in a special in-memory data structure. Our approach is limited to the important class of applications in which the finest granularity tuples of the datacube ...
Kenneth A. Ross, Kazi A. Zaman