Roll-up or Drill-up

The word ‘up’ in the names refers to going up in concept hierarchies.

For example, we would like to know the revenue of the whole year. However, the record of data is

Date Revenue
2018-01-01 1023
2018-01-02 934
2018-12-30 1244
2018-12-31 1302

Roll-up is performed by summing up everything of the column revenue. It gives us the revenue of the whole year. Monthly and quarterly roll-up are also straightforward.