Question 1

The cardinality constraint is used to specify both the minimum and maximum participation of one entity in the relationship with the other entity.

Accepted Answer

False

Question 2

A legacy system is one that has existed in an organization for less than one year.

Accepted Answer

A legacy system is one that has been in an organization for a long period of time, often considered outdated or in need of replacement or modernization. It is not a system that has existed for less than one year.

Question 3

The notation of (1,1)is used to specify the relationship type of one-to-many.

Accepted Answer

The notation of (1,*) or (1,N) is used to specify the relationship type of one-to-many. The (1,1) notation specifies a relationship type of one-to-one.

Question 4

Relationships map and define the way in which data can be extracted from a database.

Accepted Answer

Relationships in a database determine how data is connected and can be extracted using queries that reference those relationships.

Question 5

The notation 1:N is used to specify the relationship type of one-to-many.

Accepted Answer

The notation 1:N specifies a one-to-many relationship type.

Question 6

Attributes are often called fields.

Accepted Answer

This is true, attributes and fields are typically used interchangeably to refer to data elements or properties of an object or entity.

Question 7

A collection of data representing multiple occurrences of a resource,event,or agent is known as a relation.

Accepted Answer

A relation is a table or collection of data representing multiple occurrences of a resource, event, or agent. Each row in the table represents a single occurrence, and each column represents a particular attribute or characteristic of the occurrence.

Question 8

A set of data that describes a single instance of the entity represented by a relation is known as a tuple.

Accepted Answer

A tuple represents a single row or record in a relation, containing data about a specific instance of the entity represented by the relation.

Question 9

The first step in identifying all the relationships that should be included in a model is to identify users' existing and desired information.

Accepted Answer

This statement is true. The first step in designing a data model is to gather information about the users' existing and desired information needs. This information will help in identifying all the relationships that should be included in the model.

Question 10

The customer street address is often used as the key attribute in an REA diagram.

Accepted Answer

The customer street address is not a key attribute in an REA diagram. The key attributes are typically the resources, events, and agents involved in the business process being modeled. Customer identity, such as a unique customer ID, would be a key attribute in an REA diagram.

Question 11

A primary attribute is the attribute whose value is unique for every entity that will appear in the database.

Accepted Answer

The answer of A primary attribute is the attribute whose...

Question 12

In an REA diagram,the rectangle is used to represent the composite attribute.

Accepted Answer

In an REA diagram, the oval or circle shape is used to represent the composite attribute. The rectangle shape is used to represent an entity.

Question 13

A recursive relationship occurs between two different instances of an entity.

Accepted Answer

A recursive relationship, also known as a self-referencing or self-joins relationship, occurs when an instance of an entity is related to another instance of the same entity. This can occur when, for example, an employee may be a manager of another employee, or a person may be a friend of another person.

Question 14

REA stands for resources,entities and agents.

Accepted Answer

REA stands for Resources, Events, and Agents, which is a model used in accounting information systems to describe how an organization interacts with external entities.

Question 15

The cardinality constraint is used less frequently than the participation constraint.

Accepted Answer

The participation constraint specifies the minimum and maximum number of occurrences of an entity in a relationship, while the cardinality constraint specifies the maximum number of occurrences of one entity in a relationship with another entity. Both are equally important in designing a data model.

Question 16

An entity in an accounting system can be classified as a resource,event or agent about which data are collected.

Accepted Answer

This statement is true. In an accounting system, data are collected about resources (such as assets or liabilities), events (such as transactions or changes in status), and agents (such as employees or customers) in order to facilitate record-keeping and financial reporting.

Question 17

A recursive relationship is created when there is an employee being supervised,and another employee is the supervisor.

Accepted Answer

A recursive relationship is created when an entity is related to itself in the same relationship type. In this case, an employee can supervise another employee, and at the same time, the supervisor is also an employee who can be supervised by another employee. This creates a recursive relationship.

Question 18

Representing supervisors and their employees as separate entities in the model can lead to data redundancy.

Accepted Answer

If each supervisor is linked to their employees in the model, it can lead to duplication of certain data such as employee names, contact information, and work history. This can create inefficiencies and make the model more difficult to manage. It is often better to represent these relationships through a hierarchical structure or by using a composite entity.

Question 19

The fundamental requirement for moving toward an event-driven model is the complete integration of data related to an organization's business events.

Accepted Answer

In order to implement an event-driven model, it is necessary to have all relevant data related to the organization's business events integrated into the system. This allows for real-time responses to events and a more efficient and agile business process.

Question 20

A model is a complex representation of a simple entity or phenomenon.

Accepted Answer

A model is a simplified representation of a complex entity or phenomenon.

Quiz 6: Relational Databases and SQL