Difference between Data warehouse and data mart.

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Data Warehouse

  • A Data Warehouse is a vast repository of information collected from various organizations or departments within a corporation.
  • It may hold multiple subject areas.
  • It holds very detailed information.
  • Works to integrate all data sources
  • In data warehousing, a Fact constellation is used.
  • It is a Centralized System. 
  • Data Warehousing is data-oriented. 


 Data Mart

  • A data mart is an only subtype of a Data Warehouses. It is architecture to meet the requirement of a specific user group.
  •  It holds only one subject area. For example, Finance or Sales.
  •  It may hold more summarized data.
  •  It concentrates on integrating data from a given subject area or set of source systems.
  • In Data Mart, Star Schema and Snowflake Schema are used.
  • It is a Decentralized System.
  • Data Marts is project-oriented.

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