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Let's break down the problem systematically and compute the number of tuples generated by each of the queries.
Given:
- The table has three attributes ( D1, D2, D3 ) with ( n1, n2, n3 ) distinct values respectively.
- The queries use different forms of aggregation: standard GROUP BY, GROUP BY ... WITH CUBE, and GROUP BY ... WITH ROLLUP.
Explanation of Queries
Q1: GROUP BY D1, D2, D3:
This query simply groups by all combinations of ( D1, D2, D3 ).
The total number of combinations = ( n1 \times n2 \times n3 ).
Q2: GROUP BY D1, D2, D3 WITH CUBE:
The CUBE operation generates aggregates for all possible combinations of the columns, including:
Individual values of ( D1, D2, D3 )
Combinations of two values (e.g., ( D1, D2 ); ( D1, D3 ); ( D2, D3 ))
The overall total (no specific grouping).
The total number of combinations for a CUBE with three columns is ( (n1 + 1) \times (n2 + 1) \times (n3 + 1) ).
Q3: GROUP BY D1, D2, D3 WITH ROLLUP:
The ROLLUP operation generates hierarchical aggregates:
Groups by ( D1, D2, D3 )
Groups by ( D1, D2 ) only
Groups by ( D1 ) only
Overall total (no grouping at all).
The total number of combinations for a ROLLUP on three columns is ( n1 \times n2 \times n3 + n1 \times n2 + n1 + 1 ).
Applying the Formulas to Identify the Correct Option
From the description, the results should match the formulas:
1. Q1: ( d = n1 \times n2 \times n3 )
2. Q2: ( e = (n1 + 1) \times (n2 + 1) \times (n3 + 1) )
3. Q3: ( f = n1 \times n2 \times n3 + n1 \times n2 + n1 + 1 )
Now, let's inspect the given options:
Option 1: (2, 2, 2, 6, 18, 8)
( d = 2 \times 2 \times 2 = 8 )
( e = (2 + 1) \times (2 + 1) \times (2 + 1) = 3 \times 3 \times 3 = 27 ) (This does not match 18)
( f = 2 \times 2 \times 2 + 2 \times 2 + 2 + 1 = 8 + 4 + 2 + 1 = 15 ) (This does not match 8)
Option 2: (2, 2, 2, 8, 64, 15)
( d = 2 \times 2 \times 2 = 8 )
( e = (2 + 1) \times (2 + 1) \times (2 + 1) = 3 \times 3 \times 3 = 27 ) (This does not match 64)
OLAP Operation Types
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Let's break down the problem systematically and compute the number of tuples generated by each of the queries.
Given: - The table has three attributes ( D1, D2, D3 ) with ( n1, n2, n3 ) distinct values respectively. - The queries use different forms of aggregation: standard
GROUP BY
,GROUP BY ... WITH CUBE
, andGROUP BY ... WITH ROLLUP
.Explanation of Queries
Q1:
GROUP BY D1, D2, D3
:Q2:
GROUP BY D1, D2, D3 WITH CUBE
:CUBE
operation generates aggregates for all possible combinations of the columns, including:Q3:
GROUP BY D1, D2, D3 WITH ROLLUP
:ROLLUP
operation generates hierarchical aggregates:Applying the Formulas to Identify the Correct Option
From the description, the results should match the formulas: 1. Q1: ( d = n1 \times n2 \times n3 ) 2. Q2: ( e = (n1 + 1) \times (n2 + 1) \times (n3 + 1) ) 3. Q3: ( f = n1 \times n2 \times n3 + n1 \times n2 + n1 + 1 )
Now, let's inspect the given options:
Option 1: (2, 2, 2, 6, 18, 8)
Option 2: (2, 2, 2, 8, 64, 15)
Option 3: (5, 10, 10, 500, 1000, 550)
Option 4: (4, 7, 3, 84, 160, 117)
Conclusion
The correct option is:
(4, 7, 3, 84, 160, 117)