TU Wien:Datenbanksysteme VU (Hose)/Quiz 3 (2024-03-21)

How many attributes can a relationship type have?

- 0

- 1

+ as many or as few as you want

Not every teacher supervises a student. What is the participation constraint of entity type teacher?

+ Partial

- Total

Assume every Ph.D. student is supervised by at least one teacher. What is the participation constraint of entity type student?

- Partial

+ Total

A weak entity type is typically used in which relation type?

+ 1:N

- N:M

- 1:1

ER models are used for design at the ...

+ conceptual level

- view level

- physical level

An attribute can be associated with ...?

+ A weak entity type

+ A composite attribute

+ An entity type

+ A relationship type

- Another simple attribute

What is the cardinality ratio for the following relationship type? [0,1] - [0,1]

+ 1:1

- N:1

- N:M

- 1:N

What is the cardinality ratio for the following relationship type? [0,*] - [0,*]

- 1:1

- N:1

+ N:M

- 1:N

What is the cardinality ratio for the following relationship type? [0,*] - [0,1]

- 1:1

- N:1

- N:M

+ 1:N

A sales order is associated with many sales order lines. The cardinality ratio between "sales order" and "sales order lines" is?

- 1:1

+ 1:N

- N:M

Which type of keys are clearly identified in an ER diagram?

+ Primary keys

- Foreign keys

- Candidate keys

- Super keys

- Car keys

Assume you need to store information in a database about which students like which beers. How would you store this?

+ As an N:M relationship type between the beer and the student entity types

- As a 1:N relationship type between the beer and the student entity types

- As an attribute of the student entity type

- As a 1:1 relationship type between the beer and the student entity types

- As an N:1 relationship type between the beer and the student entity types

Consider the following 3 scenarios. Which of them fulfills the following function: Journal x Article -> Author

- Scenario 1

+ Scenario 2

+ Scenario 3

Consider the following 3 scenarios. Which of them fulfills the following function: Author x Article -> Journal

+ Scenario 1

+ Scenario 2

- Scenario 3