Big-Data
December 9, 2023Question 2445 – KVS 30-12-2018 Part B
December 9, 2023Relational-databases
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Question 2
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Consider the following three relations in a relational database.
Employee ( eId , Name ), Brand ( bId , bName ), Own ( eId , bId )
Which of the following relational algebra expressions return the set of elds who own all the brands?
Employee ( eId , Name ), Brand ( bId , bName ), Own ( eId , bId )
Which of the following relational algebra expressions return the set of elds who own all the brands?
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Question 2 Explanation:
Option (A) returns eid’s which owns every brand of the relation Brand.
In relational algebra, divide (/) is not a basic operator and it can be derived from the basic operators. In option (B), the divide operator is derived using basic operators and which is equivalent to option (A)
In relational algebra, divide (/) is not a basic operator and it can be derived from the basic operators. In option (B), the divide operator is derived using basic operators and which is equivalent to option (A)
Correct Answer: B
Question 2 Explanation:
Option (A) returns eid’s which owns every brand of the relation Brand.
In relational algebra, divide (/) is not a basic operator and it can be derived from the basic operators. In option (B), the divide operator is derived using basic operators and which is equivalent to option (A)
In relational algebra, divide (/) is not a basic operator and it can be derived from the basic operators. In option (B), the divide operator is derived using basic operators and which is equivalent to option (A)