Friday, April 12, 2019

Datamarts

Datamart is the subset (a part) of the Data Warehouse. Datamart focuses on a particular subject or a small business unit where as Data warehouse is one unit which contains all the business units.
Examples of Datamarts are sales, finance, Hr and so on.



There are two approaches in creating for Designing Datamarts or Data Warehouse. 

Bottom-up Design : This approach is introduced by 'Ralph Kimball'. Here first Datamarts are created and after that data warehouse is created. Later on the Datamarts are integrated to built complete data Warehouse. 

Top-Down Design : This approach is introduced by 'Inmon'. Here first Data warehouse is create and after that Datamarts are created. Later on Datamart are created from the Data Warehouse.

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