OLAP

Online Analytical Processing. OLAP was designed to change the way people use databases for reporting. Instead of running reports against a production system, first a data warehouse is created, usually using a star schema. This reporting warehouse has been optimized to improve the speed in executing queries, whereas most production, transactional systems are built for very fast inserts and updates.

Some OLAP reporting tools are Microstrategy, Brio, Cognos and even SAS.

See also DSS.

On-Line Analytical Processing (OLAP) Databases are based around the concept of amalgamating data together to make retrieving it more efficient. Replication of the same data is ok in an OLAP system. Also, the database tends to be write-restrictive. This means that data is written to it very infrequently, usually on daily, weekly, monthly, or yearly intervals. Normalization, the way On-Line Transaction Processing (OLTP) Tables are optimized, is thrown out the window. Data is grouped by dimension and fact tables. Dimension Tables usually hold the structures on how data relates. Fact Tables hold the core data. (I.E. sales per month) The tables might be detailed or contain summarized data.