A subset of a data warehouse focused on a specific business area, such as sales, finance, or operations.
A data mart contains a curated slice of the data warehouse tailored to the needs of a particular team or department. Rather than giving every analyst access to the entire warehouse, a data mart provides a focused, pre-organized view that is faster to query and easier to understand.
Example: A provincial government's central data warehouse holds data from all departments. The finance team uses a data mart that contains only budget, expenditure, and revenue data — pre-aggregated and structured for financial reporting. The GIS team has a separate spatial data mart.
Data marts reduce complexity for end users and can improve query performance by limiting the scope of data that needs to be searched.