Hassan, Ali, Ravat, Franck, Teste, Olivier, Tournier, Ronan and Zurfluh, Gilles (2015) Differentiated Multiple Aggregations in Multidimensional Databases. LNCS journal Transactions on Large-Scale Data- and Knowledge-Centered Systems, 21. pp. 20-47.

Preview

Text Download (3MB) | Preview

Abstract

Many models have been proposed for modeling multidimensional data warehouse and most consider a same function to determine how measure values are aggregated according to different data detail levels. We provide a conceptual model that supports (1) multiple aggregations, associating to the same measure a different aggregation function according to analysis axes or hierarchies, and (2) differentiated aggregation, allowing specific aggregations at each detail level. Our model is based on a graphical formalism that allows controlling the validity of aggregation functions (distributive, algebraic or holistic). We also show how conceptual modeling can be used, in an R-OLAP environment, for building lattices of pre-computed aggregates.