1
In an e-r diagram double lines indicate
Correct Answer
Total participation.
☑ MCQ PRACTICE
Database Management Systems Unit 1
Practice objective questions for quick revision and examination preparation. Try answering each question before revealing the answer.
Database Management Systems - Unit-1
2
Relationships among relationships can be represented in an-E-R model using
Correct Answer
Aggregation
3
In the relational model, cardinality is termed as:
Correct Answer
Number of tuples.
4
In the architecture of a database system external level is the
Correct Answer
view level.
5
An entity set that does not have sufficient attributes to form a primary key is a
Correct Answer
weak entity set.
6
In a Hierarchical model records are organized as
Correct Answer
Tree.
7
In an E-R diagram attributes are represented by
Correct Answer
ellipse.
8
In an E-R diagram an entity set is represent by a
Correct Answer
rectangle.
9
A relational database developer refers to a record as
Correct Answer
a tuple.
10
Which of the following are the properties of entities?
Correct Answer
Attributes
11
Which of the following operation is used if we are interested in only certain columns of a table?
Correct Answer
PROJECTION
12
Which database level is closest to the users?
Correct Answer
External
13
Which are the two ways in which entities can participate in a relationship?
Correct Answer
Total and partial
14
In E-R Diagram derived attribute are represented by
Correct Answer
Dashed ellipse
15
In E-R Diagram relationship type is represented by
Correct Answer
Diamond
16
Hierarchical model is also called
Correct Answer
Tree structure
17
In E-R diagram generalization is represented by
Correct Answer
Triangle
18
In the relational model, cardinality is termed as:
Correct Answer
Number of tuples.
19
The attribute name could be structured as an attribute consisting of first name, middle initial, and last name. This type of attribute is called
Correct Answer
Composite attribute
20
The attribute AGE is calculated from DATE_OF_BIRTH. The attribute AGE is
Correct Answer
Derived
21
Course(course_id,sec_id,semester) Here the course_id,sec_id and semester are __________ and course is a _________
Correct Answer
Attributes, Relation
22
Department (dept name, building, budget) and Employee (employee_id, name, dept name, salary) Here the dept_name attribute appears in both the relations. Here using common attributes in relation schema is one way of relating ___________ relations.
Correct Answer
Tuple of distinct
23
Database __________ which is the logical design of the database, and the database _______ which is a snapshot of the data in the database at a given instant in time.
Correct Answer
Schema, Instance
24
Student(ID, name, dept name, tot_credits) In this Schema which attributes form the primary key?
Correct Answer
ID