Online analytical processing. OLAP functionality is characterized by dynamic, multidimensional analysis of historical, current, and projected data, which supports activities such as the following:
Calculating across dimensions and through hierarchies
Analyzing trends
Drilling up and down through hierarchies
Rotating to change the dimensional orientation
Refining queries
Modeling, forecasting, and performing "what-if" analyses
OLAP tools can run against a multidimensional database or interact directly with a relational database.