1. A view of database that appears to an application program is known as:
A) Subschema
B) Schema
C) Virtual table
D) None of the above
Correct Answer: Subschema
Explanation : A view of database that appears to an application program is known as Subschema.
2. How many types of keys in Database Design?
A) Foreign key
B) Primary key
C) Candidate key
D) All of the Above
Correct Answer: All of the Above
3. Row is synonymous with the term: a. b. c. d.
A) Record
B) Relation
C) tuple
D) A & C
Correct Answer: A & C
Explanation : In a database, row is also known as tuple or record whereas column is known as field.
4. In E-R model the details of the entities are hidden from the user. This process is called _____?
A) Generalization
B) Abstraction
C) Specialization
D) None of these
Correct Answer: Abstraction
Explanation : 0In E-R model the details of the entities are hidden from the user. This process is called Abstraction.
5. An entity in A is associated with at most one entity in B, and an entity in B is associated with at most one entity in A. This is called as _____?
A) One-to-many
B) One-to-one
C) Many-to-one
D) Many-to-many
Correct Answer: One-to-one
Explanation : An entity in A is associated with at most one entity in B, and an entity in B is associated with at most one entity in A. This is called as One-to-one.
6. The degree of a relationship refers to the:
A) Number of entities
B) Maximum cardinality
C) Minimum cardinality
D) Number of attributes in the identifiers
Correct Answer: Number of entities
Explanation : The degree of a relationship refers to the Number of entities.
7. In an E-R diagram an entity set is represent by a
A) rectangle
B) ellipse
C) diamond box
D) circle
Correct Answer: rectangle
Explanation : In an E-R diagram an entity set is represent by a rectangle shape.
8. A domain is atomic if elements of the domain are considered to be ____________ units.
A) Divisible
B) Different
C) Indivisbile
D) Constant
Correct Answer: Indivisbile
Explanation : A domain is atomic if elements of the domain are considered to be Indivisbile units.
9. An example of a multi-valued attribute might be ______?
A) Student_Address
B) College_Degree
C) Student_GPA
D) ID_Number
Correct Answer: College_Degree
Explanation : An example of a multi-valued attribute might be College_Degree.
10. Relationships among entities of a single class are called _____________.
A) IS-A relationships
B) Recursive relationships
C) HAS-A relationships
D) None
Correct Answer: Recursive relationships
Explanation : Relationships among entities of a single class are called Recursive relationships.
11. Which refers to connecting entities of different types when identifiers are different?
A) HAS-A relationships
B) IS-A relationships
C) Binary relationship
D) None
Correct Answer: HAS-A relationships
Explanation : HAS-A relationships refers to connecting entities of different types when identifiers are different.
12. In an E-R diagram a ellipse represents Attribute.
A) Weak entity
B) Relationship
C) Attribute
D) Entity class
Correct Answer: Attribute
Explanation : In an E-R diagram a ellipse represents Attribute.
13. Entity is a _________.
A) Object of relation
B) Thing in real world
C) Present working model
D) Model of relation
Correct Answer: Thing in real world
Explanation : Entity is a Thing in real world.
14. An entity type whose existence depends on another entity type is called _________ entity?
A) Strong
B) Weak
C) Dependent
D) Variant
Correct Answer: Weak
15. Which is not included in the definition of an entity?
A) Person
B) Object
C) Concept
D) Action
Correct Answer: Action