Question 16776 – Data-Structures
December 19, 2023Question 14308 – Database-Management-System
December 19, 2023Question 14295 – Database-Management-System
Consider the following statements S1 and S2 about the relational data model:
S1: A relation scheme can have at most one foreign key.
S2: A foreign key in a relation schema R cannot be used to refer to tuples of R.
Which one of the following choices is correct?
Correct Answer: B
Question 3 Explanation:
- A database table may have more than one foreign key, and each foreign key can have a different parent table. Hence, the statement I is incorrect.
- A foreign key is a set of attributes in a table that refers to the primary key of another table or to the primary key of the same table (self-referential table). Hence, the statement II is also incorrect.
S1 is false and S2 is true.
Both S1 and S2 are false.
Both S1 and S2 are true.
S1 is true and S2 is false.
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