Section 3 Oracle Quiz

Test: Quiz: Identifying Relationships

1. What are the three properties that every relationship should have?

• Transferability, degree, name
• Name, optionality, degree (*)
• A UID bar, a diamond, an arc
• Name, optionality, arcs

2. Relationships can be either mandatory or optional. True or False?

• True (*)
• False

3. In a business that sells computers, choose the best relationship name from CUSTOMER to ITEM (computer, in this case).

• Each CUSTOMER must be the buyer of one or more ITEMS. (*)
• Each CUSTOMER must be the seller of one or more ITEMS.
• Each CUSTOMER may be the maker of one or more ITEMS.
• Each CUSTOMER may be the producer of one or more ITEMS.

4. Relationships always exist between

• 3 or more entities
• 2 entities (or one entity twice)  (*)
• 2 attributes
• 3 or more attributes

Test: Quiz: ER Diagramming

1. Attributes are written inside the entity to which they belong. True or False?

• True (*)
• False

2. Entity boxes are drawn as

• Soft Boxes (*)
• Hard Boxes
• Bold Circles
• Normal Circles

3. Entity names are always plural. True or False?

• True
• False (*)

4. Which symbol is used to indicate that a particular attribute is optional?

• *
• o  (*)
• #
• &

5. On an ER diagram which symbol identifies an attribute as part of a unique identifier.

• #  (*)
• *
• o
• x

6. Consider the recommended drawing conventions for ERD’s. Indicate which of the following accurately describes diagramming conventions for entities and attributes:

• The * means that an attribute is optional and entity names should be plural verbs
• The ‘o’ means that the attribute is optional and entity names should be plural verbs
• The * means that an attribute is mandatory or required and the entity name should be singular  (*)
• The ‘o’ means that the attribute is mandatory or required and the entity name should be a singular noun

Test: Quiz: Speaking ERDish and Drawing Relationships

1. Two entities can have one or more relationships between them. True or False?

• True (*)
• False

2. After looking at the diagram, choose the sentence below that could be “read” from the existing relationship (even though you’re missing relationship labels!)

• Each Student must have one or more Activities.
• Each Activity may be performed by one or more Students.
• Each Student may participate in one or more Activities. (*)
• Each Activity must belong to one and only one Student.

3. When reading a relationship between 2 entities, the relationship is only read from left to right. True or False?

• True
• False (*)

Test: Quiz: Matrix Diagrams

1. A Matrix Diagram will help you with all of the following except:

• Defining Relationships Between Entities
• Identifying Entities
• Defining Instances of Entities (*)
• Naming Relationships

2. Matrix Diagrams helps verify you have identified all possible relationships between your existing entities. True or False?

• True (*)
• False

3. Creating a Matrix Diagram is mandatory when doing Data Modeling. True or False?

• True
• False (*)