chapter 7

Question 1

what is ERD’s main components?

Answer 1

entity
attribute
relationships

Question 2

t or f: in chen and crow’s foot models, entity is represented by rectangle with attribute’s name?

Answer 2

false

Question 3

….. attributes represented by ovals
connected to an entity rectangle with a line?

Answer 3

Chen notation

Question 4

….. set of possible values for an attribute

Answer 4

domain

Question 5

…. one or more attributes that uniquely
identify each entity instance

Answer 5

identifiers

Question 6

t or f: simple attribute can be subdivided?

Answer 6

false

Question 7

t or f : attributes need to be physically stored within DB?

Answer 7

false

Question 8

t or f: relationships can be classified as 1:1?

Answer 8

false

Question 9

…. Expresses minimum and maximum number of entity occurrences associated with one occurrence of a related entity

Answer 9

cardinality

Question 10

…. Entity can exist apart from one or more related entities

Answer 10

Existence independence

Question 11

t or f: Entity can exist apart from one or more related entities

Answer 11

true

Question 12

….. Exists when PK of a related entity contains PK component of a parent entity

Answer 12

strong relationship