Accessing Subsets of Data: Data Marts

A data mart is a data repository where you store the results of a report as a relational table in a data warehouse. After creating a data mart, you can use it as a source table in your projects, and execute reports against it.

The primary objective of building a data mart is to provide an alternative location for storing frequently-used data that pertains to a particular business process or unit. This enables reports to pull data more effectively and efficiently for analysis and decision making. You can use data marts to achieve many business needs, including the following:

• Create aggregate fact tables. Aggregate fact tables improve the response time for reports that request summarized data from the warehouse.
• Create tables for very large results sets and then use other applications such as Microsoft Excel or Microsoft Access to access the data. This allows you to create a single table to feed a mass-mailing software tool or a similar closed-loop application.
• Create tables for offline analysis using direct SQL queries.
• If you have data in an MDX source, such as an SAP BW cube, you can transfer that data to a data mart and use features that cannot be used directly on MDX reports. These features include, but are not limited to custom groups, consolidations, and metrics with complex definitions.

  For information on using MDX data sources, see the MDX Cube Reporting Help.

This section contains information on how to create a data mart in MicroStrategy Developer, by creating and executing a data mart report which then creates a data mart table. It also shows you how to run standard MicroStrategy reports against your new data mart table, using the data mart table as a source table in the project in which the data mart was created.