Differentiate between Data marts and Meta data.

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The difference between data mart and metadata are as follows:- 

DATA MARTS

• Data marts can be considered as the database or collections of databases that are designed to help managers in making strategic decisions about business and the organization. Data marts are usually smaller than data warehouses as they focus on some subject or a department of an organization (a data warehouse combines databases across an entire enterprise).

• A Data Mart is focused on a single functional area of an organization and contains a subset of data stored in a Data Warehouse. A Data Mart is a condensed version of a Data Warehouse and is designed for use by a specific department, unit, or set of users in an organization. E.g., Marketing, Sales, HR, or finance. It is often controlled by a single department in an organization.

• Data Mart usually draws data from only a few sources compared to a Data warehouse. Data marts are small in size and are more flexible compared to a Datawarehouse.


Metadata

  • Metadata is defined as data about data that describes the data warehouse. The data that is used to represent other data is known as metadata. 
  • For example, the index of a book serves as metadata for the contents in the book. In other words, we can say that metadata is the summarized data that leads us to detailed data. There are two types of metadata in data warehousing:

  • Technical Metadata comprises information that can be used by developers and managers when executing warehouse development and administration tasks.
  • Business Metadata includes information that offers an easily understandable standpoint of the data stored in the warehouse.


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