Which is a way to perform drill-down?

Step down a concept hierarchy or add a dimension

Drilling down on Q1 sales of 5 lakh in a time hierarchy shows what?

Sales for all quarters combined

Year not given

Define drilling

Define drilling with example.

Drilling (drill-down) is an OLAP operation that moves from summarised data to more detailed data. It is done by stepping down a concept hierarchy (e.g. year → quarter → month → day) or by introducing an additional dimension. The reverse operation is roll-up (drill-up).

Example: a report shows sales by quarter: Q1 = 5 lakh. Drilling down on Q1 shows sales for January, February and March separately. Drill-down by adding a dimension would split the same figure by item type.

 Year 2025 -> Q1, Q2, Q3, Q4 -> Jan, Feb, Mar ...
        (drill-down ->)   (<- roll-up)

✓ Answer checked by Claude Opus 5.5 (high effort)

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