diff. b/w ROLAP and MOLAP

Wed, 19 Oct 2011 06:38:52 GMT

hi,

i want to know the difference between ROLAP and MOLAP. and what is use in qlikview.

all type of answers are welcome.

diff. b/w ROLAP and MOLAP

suniljain — Wed, 19 Oct 2011 07:57:51 GMT

ROLAP means Relational OnLine Analytical Processing

The underlying data in this model is stored in relational databases.
Since the data is stored in relational databases this model gives the appearance of traditional OLAP’s slicing and dicing functionality.

MOLAP means Multidimensional OnLine Analytical Processing

This is the traditional mode in OLAP analysis. In MOLAP data is stored in form of multidimensional cubes and not in relational databases.

ROLAP

Advatages -
The advantages of this model is it can handle a large amount of data and can leverage all the functionalities of the relational database.

Disadvantages -
The disadvantages are that the performance is slow and each ROLAP report is an SQL query with all the limitations of the genre. It is also limited by SQL functionalities

ROLAP vendors have tried to mitigate this problem by building into the tool out-of-the-box complex functions as well as providing the users with an ability to define their own functions.

MOLAP

Advantages -
The advantages of this mode is that it provides excellent query performance and the cubes are built for fast data retrieval. All calculations are pre-generated when the cube is created and can be easily applied while querying data.

Disadvantages -
The disadvantages of this model are that it can handle only a limited amount of data. Since all calculations have been pre-built when the cube was created, the cube cannot be derived from a large volume of data. This deficiency can be bypassed by including only summary level calculations while constructing the cube. This model also requires huge additional investment as cube technology is proprietary and the knowledge base may not exist in the organization.

diff. b/w ROLAP and MOLAP

Wed, 19 Oct 2011 08:39:19 GMT

hi sunil,

ok that is fine, i also want to know what is use in qlikview(ROLAP or MOLAP) and why??

topic diff. b/w ROLAP and MOLAP in QlikView

diff. b/w ROLAP and MOLAP

diff. b/w ROLAP and MOLAP

diff. b/w ROLAP and MOLAP