Quiz on Entity Relationship Modeling

What does the ER model form the basis of?

• Entity Relationship Diagram

• Relational Database

• Data Warehouse

• Data Mining

In the context of ER modeling, what does an entity refer to?

• A row in a table

• A single occurrence of data

• A set of related data

• A table in a database

Which notation represents attributes as ovals connected to an entity rectangle?

• Crow's Foot notation

• Chen notation

• Relational notation

• Object-oriented notation

What type of attribute must have a value?

• Multivalued attribute

• Required attribute

• Composite attribute

• Optional attribute

What is the term for the maximum number of entity occurrences associated with one occurrence of a related entity?

• Connectivity

• Cardinality

• Multiplicity

• Degree

Which relationship classification indicates that one entity can be associated with many occurrences of another entity?

• M:1

• 1:1

• 1:M

• M:N

What is a derived attribute?

• An attribute that must be stored

• An attribute that cannot be subdivided

• An attribute that has multiple values

• An attribute that can be calculated from others

What is the first step in developing an ER diagram?

• Revise and review the ERD

• Identify main entities and relationships

• Create a detailed narrative of operations

• Identify attributes and primary keys

What type of relationship involves three entities?

• Unary relationship

• Binary relationship

• Ternary relationship

• Quaternary relationship

Which of the following is NOT a characteristic of attributes?

• They can be required or optional

• They can be composite or simple

• They must always be stored in the database

• They can share a domain