Database-Management-System
August 29, 2024Database-Management-System
August 29, 2024Database-Management-System
|
Question 351
|
Consider join of a relation R with a relation S. If R has m tuples and S has n tuples then maximum and minimum sizes of the join respectively are
|
m+n and O
|
|
|
mn and O
|
|
|
m+n and m-n
|
|
|
mn and m+n
|
Question 351 Explanation:
For maximum no. of tuples,
If every row of r matches with each row of s, i.e., it means, the join attribute has the same value in all the rows of both r and s, then maximum mn tuples possible.
For minimum no. of tuples, if condition of join is not satisfied for any tuple then, minimum 0 tuples will be there.
If every row of r matches with each row of s, i.e., it means, the join attribute has the same value in all the rows of both r and s, then maximum mn tuples possible.
For minimum no. of tuples, if condition of join is not satisfied for any tuple then, minimum 0 tuples will be there.
Correct Answer: B
Question 351 Explanation:
For maximum no. of tuples,
If every row of r matches with each row of s, i.e., it means, the join attribute has the same value in all the rows of both r and s, then maximum mn tuples possible.
For minimum no. of tuples, if condition of join is not satisfied for any tuple then, minimum 0 tuples will be there.
If every row of r matches with each row of s, i.e., it means, the join attribute has the same value in all the rows of both r and s, then maximum mn tuples possible.
For minimum no. of tuples, if condition of join is not satisfied for any tuple then, minimum 0 tuples will be there.