
134 IBM Cognos Dynamic Cubes
6.1 Overview of virtual cubes
A virtual cube is a logical cube that is defined by merging two existing cubes. You can use
virtual cubes to join two cubes with the same structure to facilitate data management, or to
join two cubes that share only some dimensions to make calculations on the shared data. You
can merge two source cubes, two virtual cubes, or one virtual cube and one source cube. The
resulting virtual cubes can also be merged with other source cubes or virtual cubes.
For example, Figure 6-1 shows cubes that are combined to form virtual cubes. Cube A and
Cube B are merged to form the Virtual Cube AB. Then, ...