Impact size cubes when adding a level?

[FabriceH]

You have a DB with dimentions in a starschema with 3 levels and you integrate them in a cube A. There is no history in it.
What is the size impact when I add a 4th level (with surrogate key) in the DB and I create a new cube B with the 4 levels? (So I also can keep historical data)

Will it dubble the size of the cube? (B = 2 * A)?

cheers,
F ---------------------------------
Best Regards,
Fabrice

 

[jbecher]

Cube size is more dependent on number of categories than number of dimension or levels. If the level that you add has more categories than all the other dimensions/levels combined, then expect the cube size to double (or more).

Cubes size is sometimes tricky... you might think that if a cube has one year of sales data and then another year is added then the cube double in size. This is not usually the case. If you continue to sell the same products to the same customers both years, then the cube will grow very little when adding an entire new year of sales. This is because new categories are only being added to the time dimension and not in the customer and product dimensions.

It's all about category counts - to see counts per dimension and level: right click the dimension map --> Show Counts.

HTH,

Justin