A central repository for all or significant parts of the data that an organization’s various business systems collect. A data warehouse tends to be a strategic but somewhat unfinished concept. Data warehousing emphasizes the capture of data from diverse sources for useful analysis and access, but does not generally start from the point-of-view of the end user who may need access to specialized data marts. There are two approaches to data warehousing: The top down approach spins off data marts for specific groups of users after the complete data warehouse has been created. The bottom up approach builds the data marts first and then combines them into a single, all-encompassing data warehouse. SYNONYM. Data mart