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Question:  What is the difference between choosing a multidimensional database and a relational database?



January 01, 2009 03:04:21 #3
 malay_dutta   Member Since: January 2009    Total Comments: 1 

RE: What is the difference between choosing a multidimensional database and a relational database?
 
An MDDB is generally used where large number of aggregations and summarizations are required along with a very fast retrieval of data.Here the data is stored in the form of multidiemnsional cube(however physically it is also implemented in the form of multidimensional pointers) rather than 2 dimensional regular tables.Here the data retrieval is very fast due to the concept of Sparse and Dense dimensions which helps in searching of data only in concerned blocks.However it is not capable of handling large volumes of data so practically MDDB is mainly placed over some very distinctive modules like Finance(where users cannot afford to wait while retrieving the records).Order Mnagement and Procurement still use the same RDBMS approach.

The answer is right but I would just add a precaution that an MDDB should not be used if  it contains a large number of sparse values else it is just a waste of space.
 
     

 

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