Online analytical processingOLAP is the manipulation of information to support decision making

MultidimensionalGiven a relation used for data analysis, we can identify some of its attributes as measure attributes, since they measure some value, and can be aggregated upon.Dimension attribute define the dimensions on which measure attributes, and summaries of measure attributes, are viewed.

RollupThe opposite operation”that of moving fromcoarser-granularity data to finer-granularity data”is called a drill down.

Two dimensional cubeEach cell in the cube is identified for the values for the three dimensional attributes.

Both a and bFor eg., The item name and colour is viewed for a fixed size.

Slicepivot (sum(quantity) for color in ('dark','pastel','white')) .

OLAP