OLAP Cube Definition

An OLAP Cube is a data structure that allows fast analysis of data according to the multiple Dimensions that define a business problem.  A multidimensional cube for reporting sales might be, for example, composed of 7 Dimensions: Salesperson, Sales Amount, Region, Product, Region, Month, Year.

OLAP Cube Advantages

The arrangement of data into Cubes overcomes a limitation of relational databases, which are not well suited for near instantaneous analysis and display of large amounts of data. Instead, they are better suited for creating records from a series of transactions known as OLTP or On-Line Transaction Processing. Although many report-writing tools exist for relational databases, these are slow when the whole database must be summarized, and present great difficulties when users wish to re-orient reports or analyses according to different, multidimensional perspectives, aka, Slices. The use of Cubes facilitate this kind of fast end-user interaction with data

An OLAP Cube can be thought of as an extension of the modeling structure provided by a spreadsheet, which accommodates data in rows and columns–i.e., a two-dimensional array of  data.  A Cube can accommodate any number of arrays, or Dimensions, though designers of OLAP Cubes will try to build models that balance user needs and logical model limitations.