Week 4 - OLAP

Question 1

List all 5 OLAP operations

Answer 1

Roll-Up
Drill-Down
Slice and Dice
Pivot (Rotate)

Question 2

What does Roll-Up mean?

Answer 2

Roll-Up refers to the process of summarizing data by reducing the aggregation level of fact values and doing.a further aggregation.

Question 3

What is the difference between a hierarchical roll-up and dimensional roll-up?

Answer 3

HRU: Performed on fact table and some dimension tables by climbing up the hierarchy.
DRU: Are done solely on the fact table and some dimension tables by climbing up the attribute hierarchies.

Question 4

What does drill down mean?

Answer 4

Access successively deeper levels of a hierarchically organised database, set of files, etc.