Microsoft® SQL Server 2012 Unleashed

OLAP Versus OLTP

One of the primary goals of OLAP is to increase data retrieval speed for business-related queries that are critical to decisions. Very often, there is a need to broaden the scope of a business query or to drill down into more granular details of the query. OLAP was created to facilitate this type of capability. A multidimensional schema is not a typical normalized relational database; redundant data is stored to facilitate quick retrieval. The data in a multidimensional database should be relatively static; in fact, data is not useful for decision support if it changes constantly. The information in a data warehouse is built out of carefully chosen snapshots of business data from OLTP systems. If you capture data at the right ...