A Data Mart system consists primarily of three components: Data Mart database, query/user interface software, and interfaces to extract data from operational databases and “add value” to that data to make it more usable for managers and analysts.
Data Marts extract data selectively from existing operational databases such as Accounting, Forecasting, Marketing, and Human Resources.
The user interface query tool allows executives and other users real-time access to the Data Mart for query generation, result displays, reports and data exports.
The database interfaces allow for warehouse database updating on a continual, daily, weekly or monthly basis. These interfaces are typically more than simple transfers of data from the operations database(s) to the data warehouse. They also consist of value-added processes that re-package the data and perform other operations such as pre-calculation of totals and ratios. In their most elegant form, the interfaces are “bridges” into the operational databases that allow the query tool to access the data in its source environment. When these bridges can be constructed, the data need not be transported which reduces potential transfer problems, reduces burdens on IT staff, and allows data to be available in real-time.