RE: what is the main FUNCTIONAL difference between RO...
Rolap is relational Database ,based on Star schema Molap is Multidimensional Schema based on the Olap model or the Cube wheras HOLAP is the hybrid of the both
RE: what is the main FUNCTIONAL difference between ROLAP,MOLAP,HOLAP?
Rolap : Relational Olap,these functionality are used in Business Objects. Molap : Multi Dimensional Olap Functionality are used in Cognos. Hloap : Hybrid Olap is a combination of Rolap and Molap.
RE: what is the main FUNCTIONAL difference between ROLAP,MOLAP,HOLAP?
The FUNCTIONAL difference between these is how they information is stored. In all cases, the users see the data as a cube of dimensions and facts.
ROLAP - detailed data is stored in a relational database in 3NF, star, or snowflake form. Queries must summarize data on the fly.
MOLAP - data is stored in multidimensional form - dimension and facts stored together. You can think of this a a persistent cube. Level of detail is determined by the intersection of the dimension hierarchies.
HOALP - data is stored using a combination of relational and multi-dimensional storage. Summary data might persist as a cube, while detail data is stored relationally, but transitioning between the two is invisible to the end-user.
