Superclass/Subclass Relationship Types in Logical Data Model

18 Questions

What is the most appropriate option to represent a superclass/subclass relationship in a logical data model?

Creating one relation

In a superclass/subclass relationship, what factors determine the most appropriate representation?

Disjointness and participation constraints

For : binary relationship types, what should be posted into a new relation as foreign keys?

Primary key attributes of the entities involved

Which type of relationship involves creating a new relation to represent the relationship along with its attributes?

Complex relationship

What forms the primary key of a new relation in : binary relationship types?

Foreign keys and some relationship attributes

In logical data modeling, what is a common approach to represent a superclass entity?

As a parent entity

What is the first step in deriving relations for a logical data model?

Identify the parent entity

How are parent and child entities designated in a one-to-many (1:*) binary relationship?

Parent entity has the foreign key attribute

What is considered when deciding to create relations for a one-to-one (1:1) binary relationship?

Participation

In a 1:1 relationship with mandatory participation on both sides, what approach is taken in creating relations?

Create two separate relations

What does cardinality describe in entity relationship modeling?

Number of possible relationships for each participating entity

How does participation influence relationships in logical data modeling?

'Joins' entities together

In a 1:1 relationship with optional participation on both sides, how is the parent and child entity designated?

Parent and child entities are arbitrarily designated

What are the rules for participation in a 1:1 recursive relationship with mandatory participation on both sides?

Create a single relation with two copies of the primary key; one as primary key and the other as foreign key

Which entity is designated as the parent in a 1:1 Staff Uses Car relationship?

Staff entity

How are attributes in a relationship ordered if there are one or more attributes involved?

Attributes should follow the child's primary key

When designing a 1:1 relationship, what determines the designation of parent and child entities?

Optional participation on both sides

In a 1:1 recursive relationship with only one side having mandatory participation, what can be done?

Create a new relation to represent the relationship

This quiz covers the process of deriving relations for a logical data model, focusing on superclass/subclass relationship types. Topics include identifying superclass as the parent entity, representing the relationship as one or more relations, and factors affecting the representation choice.

Make Your Own Quizzes and Flashcards

Convert your notes into interactive study material.