\section{OLAP operators}

OLAP (Online Analytical Processing) is an approach to quickly providing 
answers to analytical queries that are multidimensional in nature. 
Usually, the basics of OLAP is a set of SQL queries which will typically 
result in a matrix (or pivot) format. The dimensions form the row and column
of the matrix. \rapidminer supports basic OLAP functionality like grouping and 
aggregations.
