Question:
In a data warehouse, a 3D cube initially has dimensions: Product type, Month, and Country. After visualization, the dimension Country is refined into State. Which OLAP operation is performed?
In a data warehouse, a 3D cube initially has dimensions: Product type, Month, and Country. After visualization, the dimension Country is refined into State. Which OLAP operation is performed?
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Roll up = summarize to higher level.
Drill down = go to more detailed level.
Slicing = fix one dimension.
Dicing = create a subcube using multiple filters.
Updated On: Feb 15, 2026
- Roll up
- Slicing
- Dicing
- Drill down
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The Correct Option is D
Solution and Explanation
Step 1: Understand the given transformation.
Initially, one of the dimensions is \textit{Country}.
After visualization, Country is refined into \textit{State}.
This means we are moving from a higher level of hierarchy (Country) to a more detailed level (State).
Step 2: Recall OLAP operations.
Roll up: Aggregates data to a higher level (e.g., State to Country).
Drill down: Breaks data into more detailed levels (e.g., Country to State).
Slicing: Fixes one dimension to a single value.
Dicing: Selects a subcube by choosing specific values of multiple dimensions.
Step 3: Identify the correct operation.
Since we move from Country (general level) to State (more detailed level),
this corresponds to the Drill down operation.
Hence, the correct answer is option (D).
Initially, one of the dimensions is \textit{Country}.
After visualization, Country is refined into \textit{State}.
This means we are moving from a higher level of hierarchy (Country) to a more detailed level (State).
Step 2: Recall OLAP operations.
Roll up: Aggregates data to a higher level (e.g., State to Country).
Drill down: Breaks data into more detailed levels (e.g., Country to State).
Slicing: Fixes one dimension to a single value.
Dicing: Selects a subcube by choosing specific values of multiple dimensions.
Step 3: Identify the correct operation.
Since we move from Country (general level) to State (more detailed level),
this corresponds to the Drill down operation.
Hence, the correct answer is option (D).
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