Database-Management-System
August 29, 2024Database-Management-System
August 29, 2024Database-Management-System
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Question 690
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In relational databases, the natural join of two tables is
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cartesian product always
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combination of union and filtered cartesian product
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combination of selection and filtered cartesian product
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combination of projection and filtered cartesian product
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Question 690 Explanation:
→While performing a natural join, if there were no common attributes between the two relations, Natural join will behave as Cartesian Product.
→ Example: If the tables R and S contains common attributes and value of that attribute in each tuple in both tables are same, then the natural join will result n*m tuples as it will return all combinations of tuples.
→ Example: If the tables R and S contains common attributes and value of that attribute in each tuple in both tables are same, then the natural join will result n*m tuples as it will return all combinations of tuples.
Correct Answer: D
Question 690 Explanation:
→While performing a natural join, if there were no common attributes between the two relations, Natural join will behave as Cartesian Product.
→ Example: If the tables R and S contains common attributes and value of that attribute in each tuple in both tables are same, then the natural join will result n*m tuples as it will return all combinations of tuples.
→ Example: If the tables R and S contains common attributes and value of that attribute in each tuple in both tables are same, then the natural join will result n*m tuples as it will return all combinations of tuples.