  A new compression method called difference-Huffman coding (DHC) is introduced
in this paper. It is verified empirically that DHC results in a smaller
multidimensional physical representation than those for other previously
published techniques (single count header compression, logical position
compression, base-offset compression and difference sequence compression). The
article examines how caching influences the expected retrieval time of the
multidimensional and table representations of relations. A model is proposed
for this, which is then verified with empirical data. Conclusions are drawn,
based on the model and the experiment, about when one physical representation
outperforms another in terms of retrieval time. Over the tested range of
available memory, the performance for the multidimensional representation was
always much quicker than for the table representation.
