Pagini

Section 2
(Answer all questions in this section)

  1. The word "Volatile" means....

Changing constantly; unstable

Static; unlikely to change

Large quantity

Limited quantity


  2. In the following statements, find two examples of ENTITY: Instance. (Choose Two)

(Choose all correct answers)

DAIRY PRODUCT: milk

VEGETABLE: grows

BOOK: Biography of Mahatma Gandhi

TRAIN: runs


  3. Which of the following statements about attributes are true? (Choose Two)
(Choose all correct answers)

They describe, qualify, quantify, classify, or specify an entity.

They are often adjectives.

They have a data type such as a number or character string.

They must be single valued unless they belong to more than one entity.



  4. What is the purpose of a Unique Identifier?

To uniquely determine a table and columns within that table.

To identify a specific column within a table.

Create an entity that is unlike any other entity aside from itself.

To identify one unique instance of an entity, by using one or more attributes and/or relationships.


  5. A/an _________ is a piece of information that in some way describes an entity. It is a property of the entity and it quantifies, qualifies, classifies or specifies the entity.

ERD

Process

Table

Attribute


  6. Some of the following could be attributes of an ENTITY called PERSON. Select the incorrect attributes for PERSON. (Choose Two)

(Choose all correct answers)

Age

Freddy Wilson

Name

Priya Hansenna


  7. Unique Identifiers....

Distinguish one entity from another

Distinguish one instance of an entity from all other instances of that entity

Distinguish all entities in a database

Distinguishes nothing


  8. Which of the following entities most likely contains invalid attributes?

Entity: Home. Attributes: Number of Bedrooms, Owner, Address, Date Built

Entity: Pet. Attributes: Name, Birthdate, Owner

Entity: Car. Attributes: Owner Occupation, Owner Salary, Speed

Entity: Mother. Attributes: Name, Birthdate, Occupation, Salary


  9. In a physical data model, an attribute is represented as a/an

Column

Row

Instance

Foreign Key


  10. Entities are usually verbs. True or False?

True

False


  11. An entity may have which of the following?

Experiences

Instances

Tables

None of the above


  12. All of the following would be instances of the entity PERSON except which?

David Jones

Male

Angelina Rosalie

Grace Abinajam