OLAP operations

ROLL UP
The roll up operation aggregates the data in an increasing order in the conceptual hierarchy from a lower level to higher level. In the example mentioned before the data is aggregated by week and then the data is aggregated according to its higher level in hierarchy month and so on.

DRILL DOWN
Drill down is the opposite of roll up. The data is aggregated in decreasing order in the conceptual hierarchy from a higher level to lower level. In the time dimension the data is grouped by ‘ week’ and then the next grouping is in the lower level ‘day’.

SLICE AND DICE
Slice operation is choosing one particular dimension in the n dimensional cube which results in a sub cube where as dice operation is done by choosing two or more dimensions in the cube to result in a sub cube.

PIVOT
This is also referred as rotate where the axis is rotated to provide a different presentation of the data in the n dimensional cube.