Data Warehouse vs Data Mart

A data mart is simply a mini-data warehouse. More specifically it is a data warehouse designed for a specific purpose or to be analyzed by a particular group within the institution. Take the hospital example from above, a data mart could be created collecting various financial data specifically for analytical use by the accounting department. The data collected can be extracted either directly from the data warehouse or from individual repositories (which is where a data warehouse extracts it's data). Basically, a data warehouse collects a wide range of data types, while a data mart specifically involves only data the user will want.