UML Class Diagrams - Chapter 3 Quiz

Questions and Answers

Associations in UML Class Diagrams should include a description in which of the following situations?

The business purpose of the association is clear.

When the association is optional.

When the association is mandatory.

The business purpose of the association is not clear. (correct)

Which of the following is the best way to implement an association between a Cash Disbursements class and a Cash Accounts class?

Post the primary key of Cash Disbursements as a foreign key in Cash Accounts.

Create a separate table for the association.

Use an index in both classes.

Post the primary key of Cash Accounts as a foreign key in Cash Disbursements. (correct)

Which of the following is not a basic building block of entity-relationship diagrams (ERDs)?

Associations (correct)

Attributes

Entities

Relationships

Logical database structure models, including UML Class Diagrams, must be able to describe which of the following?

Entities in the domain of interest Signup and view all the answers

When implementing the database from a UML class diagram, associations should be mapped to which of the following?

Foreign Keys Signup and view all the answers

When implementing the database from a UML class diagram, attributes should be mapped to which of the following?

Fields Signup and view all the answers

What symbol represents aggregation in UML Class Diagrams?

Open diamond Signup and view all the answers

Which of the following best describes the purpose of a primary key?

Unambiguously identifies each instance of the class. Signup and view all the answers

Which of the following is the best description of an association?

The relationship between two classes. Signup and view all the answers

Which of the following is not a best practice in preparing UML Class diagrams?

Model each process separately. Signup and view all the answers

Which of the following is not a category of operational decision used in creating business rules?

Event Signup and view all the answers

Which of the following is not one of the building blocks used for creating UML Class Diagrams?

Events Signup and view all the answers

Which of the following is not something a model of database structures must be able to describe?

The sequence that entities are accessed. Signup and view all the answers

Which of the following is not a step in using a UML Class model to prepare a database?

Map Associations to Primary Keys. Signup and view all the answers

Study Notes

UML Class Diagrams and Associations

Associations should include descriptions when the business purpose is unclear.
An example involves a Cash Disbursements class (0..*) and a Cash Accounts class (1..1), implemented by using the primary key of Cash Accounts as a foreign key in Cash Disbursements.

Entity-Relationship Diagrams (ERDs)

ERDs share similarities with UML Class diagrams regarding content and purpose.
Associations are not considered a basic building block of ERDs.

Database Structure Models

Logical database structures, including UML Class Diagrams, must effectively describe entities in the relevant domain.
When translating UML into a database, associations should be mapped to foreign keys, while attributes correspond to fields.

Aggregation in UML

Aggregation is represented visually by an open diamond shape in UML diagrams.

Primary Keys and Associations

The primary key serves the purpose of uniquely identifying each instance of a class.
Associations define the relationships between two classes, which are crucial for understanding the data model.

Best Practices in UML Class Diagrams

Best practices advise against modeling each process separately, promoting integrated and cohesive diagrams.
Categories of operational decisions do not include events, which should not be confused with entities or attributes in UML.

Building Blocks and Structure Limitations

Building blocks for UML Class Diagrams exclude events.
Database models do not need to describe the sequence in which entities are accessed, focusing instead on structure over process order.

Steps in Database Preparation with UML

In preparing a database from UML Class models, key steps include mapping associations to foreign keys and attributes to table fields but do not involve mapping associations to primary keys.

Description

Test your knowledge on UML Class Diagrams with this Chapter 3 quiz featuring multiple-choice flashcards. Explore associations, multiplicities, and their definitions to strengthen your understanding of UML modeling concepts.