Tuesday, 7 April 2015

Relational model and Normalization Quiz 5

Relational model and Normalization Quiz

1. One or more columns of a composite primary (a primary key that comprises of more than one attribute) key can be allowed to have NULL values. TRUE / FALSE?

2. A foreign key of any table must refer to the primary key of its base table. TRUE/FALSE

3. The value of a foreign key attribute A of table R that refers to table S cannot be NULL if which of the following holds?
    If attribute A is part of a primary key attribute in R
    If attribute A refers the primary key of S
    If attribute A is UNIQUE
    If either a or b or both holds

4. An attribute must contain only values consistent with the defined data format of that particular attribute is called
    Entity integrity
    Referential integrity
    User-defined integrity
    Column integrity

5. The __________ property ensures that any instance of the original relation can be identified from corresponding instances of the smaller relations.
    Both a and b
    None of the above

6. In a functional dependency AB --> C, which of the following is true?
    A is Determinant of C
    B is Determinant of C
    Both A and B together Determine C
    All of the above

7. Which of the following is also called as Subset dependencies?
    Entity integrity constraints
    Referential integrity constraints
    User-defined integrity constraints
    Column integrity constraints

8. The determinant of a functional dependency refers to the attribute, or group of attributes, on the left-hand side of the arrow.

9. Assume a set of functional dependencies F = {Regno Name --> Gender, Regno --> Department, Regno --> Gender, Name --> Branch}. Here, Regno Name --> Gender is,
    Gender is fully funcionally dependent on Regno and Name
    Gender is partially funcionally dependent on Regno and Name
    Name and branch together form the primary key
    None of the above

10. _____________ ensure that a value that appears in one relation for a given set of attributes also appears for a certain set of attributes in another relation.
    Referential integrity constraints
    Weak entity sets
    Entity integrity constraints
    None of the above

Score =

Correct answers:

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