Multidimensional Analysis in On-Line Analytical Processing (OLAP), and Scientific and statistical databases (SSDB) use operations requiring summary information on multi-dimensional data sets. Most common are aggregate operations along one or more dimensions of numerical data values and/or on hierarchies defined on them. Simultaneous calculation of multi-dimensional aggregates are provided by the Data Cube operator, used to calculate and store summary information on a number of dimensions. This is computed only partially if the number of dimensions is large since a few dimensions are typical for analysis over summary information. Queries may either be answered from a materialized cube or calculated on the fly. The multi-dimensionality of the underlying problem can be represented both in relational and multi-dimensional databases, the latter being a better fit when query performance is the criteria for judgement. Relational databases are scalable in size for OLAP and multidimensional an...
Sanjay Goil, Alok N. Choudhary