Explain three types of data marts.

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There are three main types of data mart:-

• Dependent data mart: Dependent data marts are created by drawing data directly from operational, external, or both sources.

• Independent: Independent data mart is created without the use of a central data warehouse.

• Hybrid: This type of data mart can take data from data warehouses or operational systems.


 Dependent data mart

  • A dependent data mart allows sourcing an organization's data from a single Data Warehouse. It is one of the data marts examples which offers the benefit of centralization. U you need to develop one or more physical data marts, then you need to configure them as dependent data marts.
  • Dependent Data Mart in the data warehouse can be built in two different ways. Either where a user can access both the data mart and data warehouse, depending on need, or where access is limited only to the data mart. The second approach is not optimal as it produces sometimes referred to as a data junkyard. In the data junkyard, all data begins with a common source, but they are scrapped, and mostly junked.


Independent Data Mart

  • An independent data mart is created without the use of a central Data warehouse. This kind of Data Mart is an ideal option for smaller groups within an organization.
  • An independent data _mart has neither a relationship with the enterprise data warehouse nor with any other data mart. In an Independent data mart, the data is input separately, and its analyses are also performed autonomously. 
  • Implementation of independent data marts is antithetical to the motivation for building a data warehouse. First of all, you need a consistent, centralized store of enterprise data that can be analyzed by multiple users with different interests who want widely varying information.


Hybrid Data Mart
  • A hybrid data mart combines input from sources apart from the Data warehouse. This could be helpful when you want ad-hoc integration, like after a new group or product is added to the organization. 
  • It is the best data mart example suited for multiple database environments and a fast implementation turnaround for any organization. It also requires the least data cleansing effort. 
  • Hybrid Data Mart also supports large storage structures and it is better for flexible for smaller data-centric applications.


 Types of Data Mart:

There are three types of data marts:

1. Dependent Data Mart –



Dependent Data Mart is created by extracting the data from a central repository, Datawarehouse. A first data warehouse is created by extracting data (through ETL tool) from external sources and then a data mart is created from the data warehouse. A dependent data mart is created in a top-down approach of data warehouse architecture. This model of a data mart is used by big organizations.


2. Independent Data Mart


Independent Data Mart is created directly from external sources instead of the data warehouses. A first data mart is created by extracting data from external sources and then a data warehouse is created from the data present in the data mart. An Independent data mart is designed in a bottom-up approach of data warehouse architecture. This model of a data mart is used by small organizations and is cost-effective comparatively.


3. Hybrid Data Mart –

This type of Data Mart is created by extracting data from operational sources or from the data warehouse. 1Path reflects accessing data directly from external sources and 2Path reflects the dependent data model of the data mart.

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