data

Question 1

What does ERD stand for?

o A) Entity Relationship Data
o B) Entity Relational Diagram
o C) Entity Relationship Diagram
o D) Entity Realization Diagram

Answer 1

Entity Relationship Diagram

Question 2

Which symbol is commonly used to represent an entity in an ERD?

o A) Rectangle
o B) Oval
o C) Diamond
o D) Triangle

Answer 2

Rectangle

Question 3

What does a relationship represent in an ERD?

o A) A unique identifier
o B) A connection between entities
o C) An attribute of an entity
o D) A database table

Answer 3

A connection between entities

Question 4

Which symbol represents a relationship in an ERD?

o A) Rectangle
o B) Oval
o C) Diamond
o D) Triangle

Answer 4

Diamond

Question 5

What is the purpose of attributes in an ERD?

o A) To define the relationships
o B) To describe the properties of an entity
o C) To create entities
o D) To link tables

Answer 5

To describe the properties of an entity

Question 6

What type of attribute can have multiple values?

o A) Simple attribute
o B) Composite attribute
o C) Multi-valued attribute
o D) Derived attribute

Answer 6

Multi-valued attribute

Question 7

Which of the following best describes a composite attribute?

o A) An attribute with a unique value
o B) An attribute that can be broken down into smaller parts
o C) An attribute that is calculated from other attributes
o D) An attribute that can have multiple values

Answer 7

An attribute that can be broken down into smaller parts

Question 8

What is the role of a foreign key in a database?

o A) To uniquely identify a record
o B) To link two tables together
o C) To provide data integrity
o D) To define an attribute

Answer 8

To link two tables together

Question 9

What is the cardinality of a relationship?

o A) The number of entities involved
o B) The type of relationship
o C) The number of attributes in an entity
o D) The number of relationships in a diagram

Answer 9

The number of entities involved

Question 10

What does an oval represent in an ERD?

o A) An entity
o B) An attribute
o C) A relationship
o D) A weak entity

Answer 10

An attribute

Question 11

In ER modeling, what does ‘normalization’ refer to?

o A) Simplifying the diagram
o B) Organizing data to reduce redundancy
o C) Creating more entities
o D) Adding more attributes

Answer 11

Organizing data to reduce redundancy

Question 12

What is a derived attribute?

o A) An attribute that is static
o B) An attribute calculated from other attributes
o C) An attribute that can have multiple values
o D) An attribute that is always unique

Answer 12

An attribute calculated from other attributes

Question 13

Which of the following is NOT a type of relationship in an ERD?

o A) One-to-one
o B) One-to-many
o C) Many-to-zero
o D) Many-to-many

Answer 13

Many-to-zero

Question 14

Which of the following best describes a ‘one-to-one’ relationship?

o A) One entity relates to many entities
o B) Each entity relates to exactly one other entity
o C) Many entities relate to many entities
o D) One entity relates to zero entities

Answer 14

Each entity relates to exactly one other entity

Question 15

Which of the following is a characteristic of a primary key?

o A) It can contain duplicate values
o B) It can be null
o C) It must be unique for each record
o D) It is always an auto-increment field

Answer 15

It must be unique for each record

Question 16

Which of the following is true about weak entities?

o A) They can exist independently.
o B) They depend on a strong entity.
o C) They have their own primary key.
o D) They cannot have relationships.

Answer 16

They depend on a strong entity

Question 17

What is the significance of an ‘attribute type’?

o A) It defines the relationships between entities.
o B) It determines how data is stored.
o C) It categorizes attributes based on their functionality.
o D) It specifies the cardinality of a relationship.

Answer 17

It determines how data is stored

Question 18

Which type of diagram is used to visually represent entities and their relationships?

o A) Flowchart
o B) ERD
o C) UML diagram
o D) Class diagram

Answer 18

ERD

Question 19

What is the purpose of an ERD in database design?

o A) To document data flow
o B) To illustrate data relationships
o C) To define user interfaces
o D) To create backup plans

Answer 19

To illustrate data relationships

Question 20

Which of the following is an example of a multi-valued attribute?

o A) Date of birth
o B) Phone numbers
o C) Email address
o D) Employee ID

Answer 20

Phone numbers

Question 21

What does it mean when an entity is represented with a rounded rectangle?

o A) It is a weak entity.
o B) It is an associative entity.
o C) It is an attribute.
o D) It is a strong entity.

Answer 21

It is a strong entity

not sure

not sure 8aleban c mesh d

Question 22

Which of the following correctly represents a ‘one-to-many’ relationship?

o A) 1:1
o B) 1:N
o C) M:N
o D) N:1

Answer 22

1:N

Question 23

What is a composite key?

o A) A key composed of multiple attributes
o B) A key that is derived from other attributes
o C) A single attribute key
o D) A key that is always unique

Answer 23

A key composed of multiple attributes

Question 24

What does a ‘relationship attribute’ represent?

o A) An identifier for the relationship
o B) A property of the relationship
o C) A composite attribute
o D) An entitys primary key

Answer 24

A property of the relationship

Question 25

Which of the following represents a transformed entity? ## Footnote o A) An entity with no relationships o B) An entity derived from other entities o C) A weak entity o D) A composite entity

Answer 25

An entity derived from other entities

Question 26

What is the main goal of creating an ERD? ## Footnote o A) To implement the database o B) To visualize and communicate the data structure o C) To analyze data relationships o D) To enforce data integrity

Answer 26

To visualize and communicate the data structure

Question 27

Which of the following best describes a 'self-referential' relationship? ## Footnote o A) An entity that relates to another entity o B) An entity that relates to itself o C) An entity that has no relationships o D) An entity that can be part of multiple relationships

Answer 27

An entity that relates to itself

Question 28

What does a 'strong entity' mean? ## Footnote o A) An entity with unique attributes o B) An entity that can exist independently o C) An entity that has multiple relationships o D) An entity that has no attributes

Answer 28

An entity that can exist independently

Question 29

In ER modeling, what does 'cardinality' indicate? ## Footnote o A) The number of attributes in an entity o B) The number of entities involved in a relationship o C) The type of relationship o D) The nature of attributes

Answer 29

The number of entities involved in a relationship

Question 30

What is the function of an entity set? ## Footnote o A) To group similar entities o B) To define relationships o C) To categorize attributes o D) To represent derived attributes

Answer 30

To group similar entities

Question 31

Which of the following is an example of a derived attribute? ## Footnote o A) Age (calculated from Date of Birth) o B) First Name o C) Employee ID o D) Phone Number

Answer 31

Age (calculated from Date of Birth)

Question 32

What does EERD stand for? ## Footnote o A) Enhanced Entity Relationship Diagram o B) Extended Entity Relationship Data o C) Entity Enhanced Relationship Diagram o D) Entity Extended Relational Diagram

Answer 32

Enhanced Entity Relationship Diagram

Question 33

Which of the following is a primary purpose of an EERD? ## Footnote o A) To represent complex data relationships o B) To create database tables o C) To visualize SQL queries o D) To manage data storage

Answer 33

To represent complex data relationships

Question 34

What is a superclass in an EERD? ## Footnote o A) An entity with no attributes o B) A generalized entity that can have subclasses o C) An entity that has multiple relationships o D) A weak entity

Answer 34

A generalized entity that can have subclasses

Question 35

Which symbol is used to represent a superclass in an EERD? ## Footnote o A) Rectangle o B) Oval o C) Diamond o D) Double rectangle

Answer 35

Double rectangle

Question 36

What does a specialization hierarchy represent? ## Footnote o A) A single entity with multiple attributes o B) A relationship between two entities o C) A generalization of entities into subclasses o D) A weak entity

Answer 36

A generalization of entities into subclasses

Question 37

What is the purpose of generalization in an EERD? ## Footnote o A) To create unique identifiers o B) To combine multiple entities into a single entity o C) To define relationships o D) To categorize attributes

Answer 37

To combine multiple entities into a single entity

Question 38

What does a diamond shape represent in an EERD? ## Footnote o A) An entity o B) A relationship o C) An attribute o D) A weak entity

Answer 38

A relationship

Question 39

What is an overlapping subclass? ## Footnote o A) Subclasses that can share instances o B) Subclasses that cannot share instances o C) Subclasses derived from multiple superclasses o D) Subclasses with no relationships

Answer 39

Subclasses that can share instances

Question 40

What does a total specialization constraint indicate? ## Footnote o A) Every entity in the superclass must belong to a subclass o B) No entity in the superclass can belong to a subclass o C) Some entities in the superclass may not belong to a subclass o D) All subclasses must have attributes

Answer 40

Every entity in the superclass must belong to a subclass

Question 41

What is the role of an attribute in an EERD? ## Footnote o A) To define relationships between entities o B) To describe properties of an entity o C) To represent the hierarchy of entities o D) To manage database integrity

Answer 41

To describe properties of an entity

Question 42

In EERD, what does a weak entity depend on? ## Footnote o A) A superclass o B) Its own attributes o C) A strong entity o D) A derived attribute

Answer 42

A strong entity

Question 43

What does a 'non-weak' entity mean in EERD terminology? ## Footnote o A) An entity that can exist independently o B) An entity that has no attributes o C) An entity that is derived from another o D) An entity that is always weak

Answer 43

An entity that can exist independently

Question 44

Which of the following relationships can EERDs represent? ## Footnote o A) One-to-one o B) One-to-many o C) Many-to-many o D) All of the above

Answer 44

All of the above

Question 45

In EERDs, what does a double oval typically represent? ## Footnote o A) A composite attribute o B) A multi-valued attribute o C) A derived attribute o D) A weak entity

Answer 45

A multi-valued attribute

Question 46

Which of the following best describes the term 'inheritance' in EERDs? ## Footnote o A) Subclasses inherit attributes from their superclass o B) Entities inherit relationships from other entities o C) Attributes are inherited from attributes o D) Relationships can be inherited

Answer 46

Subclasses inherit attributes from their superclass

Question 47

How are attributes represented in an EERD? ## Footnote o A) Rectangles o B) Ovals o C) Diamonds o D) Triangles

Answer 47

Ovals

Question 48

What does a total generalization indicate? ## Footnote o A) All subclasses must be represented o B) Not all subclasses need to be represented o C) Subclasses can share instances o D) Subclasses cannot share instances

Answer 48

All subclasses must be represented

Question 49

What symbol represents a weak entity set in an EERD? ## Footnote o A) A rectangle with a double border o B) A rectangle with a dashed line o C) A rectangle with a single border o D) A rectangle with a shadow

Answer 49

A rectangle with a double border

Question 50

What is the function of a relationship in an EERD? ## Footnote o A) To define how entities are connected o B) To categorize attributes o C) To specify data types o D) To create backup relationships

Answer 50

To define how entities are connected

Question 51

What is the significance of a generalization hierarchy? ## Footnote o A) It defines the relationships between different entities o B) It groups similar entities into a single superclass o C) It specifies the attributes of an entity o D) It manages database integrity

Answer 51

It groups similar entities into a single superclass

Question 52

Which of the following is an example of a total specialization? ## Footnote o A) A superclass that may not have subclasses o B) A superclass that must have subclasses o C) A superclass with optional attributes o D) A superclass with no relationships

Answer 52

A superclass that must have subclasses

Question 53

What does a 'relationship attribute' represent in an EERD? ## Footnote o A) An attribute of an entity o B) An identifier for the relationship o C) A property of the relationship o D) An attribute of a subclass

Answer 53

A property of the relationship

Question 54

What does a double diamond represent in an EERD? ## Footnote o A) A weak relationship o B) A relationship with attributes o C) A subclass o D) A superclass

Answer 54

A relationship with attributes

Question 55

Which of the following best describes a multi-valued attribute in EERD? ## Footnote o A) An attribute with a single value o B) An attribute that can hold more than one value o C) An attribute that is derived o D) An attribute with no values

Answer 55

An attribute that can hold more than one value

Question 56

What signifies a weak relationship in an EERD? ## Footnote o A) A solid line o B) A dashed line o C) A double line o D) A dotted line

Answer 56

A dashed line

Question 57

Which of the following is NOT a feature of an EERD? ## Footnote o A) Representation of generalization o B) Representation of relationships o C) Representation of SQL queries o D) Representation of attributes

Answer 57

Representation of SQL queries

Question 58

What does a solid line with a circle indicate in an EERD? ## Footnote o A) A mandatory relationship o B) An optional relationship o C) A disjoint subclass o D) A total specialization

Answer 58

An optional relationship

Question 59

Which of the following best describes an attribute's participation in a relationship? ## Footnote o A) The number of attributes in an entity o B) The number of relationships an attribute can have o C) Whether an attribute must exist in a relationship o D) The data type of the attribute

Answer 59

Whether an attribute must exist in a relationship

Question 60

What does an attribute in an EERD typically represent? ## Footnote o A) A unique identifier for an entity o B) A connection between entities o C) A property of an entity o D) An external entity

Answer 60

A property of an entity

Question 61

What does a 'recursive relationship' mean in EERDs? ## Footnote o A) An entity relates to itself o B) An entity relates to multiple entities o C) An attribute is derived from another o D) A subclass relates to a superclass

Answer 61

An entity relates to itself

Question 62

Which of the following is true about weak entities? ## Footnote o A) They have their own primary key. o B) They depend on strong entities for identification. o C) They can exist independently of strong entities. o D) They cannot have attributes.

Answer 62

They depend on strong entities for identification

Question 63

What does a 'composite attribute' indicate in an EERD? ## Footnote o A) An attribute that can be broken down into smaller parts o B) An attribute that is derived o C) An attribute that can have multiple values o D) An attribute with no values

Answer 63

An attribute that can be broken down into smaller parts

Question 64

Which of the following is an example of a superclass-subclass hierarchy? ## Footnote o A) Employee and Manager o B) Product and Category o C) Student and Course o D) All of the above

Answer 64

All of the above ## Footnote A 8aleban

Question 65

What does a 'partial specialization' mean in EERDs? ## Footnote o A) Some entities in the superclass must belong to subclasses o B) All entities in the superclass must belong to subclasses o C) No entities in the superclass can belong to subclasses o D) Subclasses can share attributes

Answer 65

Some entities in the superclass must belong to subclasses

Question 66

What does a dashed oval represent in an EERD? ## Footnote o A) A multi-valued attribute o B) A weak attribute o C) A derived attribute o D) A mandatory attribute

Answer 66

A derived attribute