True/False
Indicate whether the
statement is true or false.
|
|
|
1.
|
Data modeling is a technique for organizing and
documenting a system's logical and physical models.
|
|
|
2.
|
An entity is a class of persons, places, objects,
events or concepts about which we need to capture and store data.
|
|
|
3.
|
An identity is a class of persons, places, objects,
events, or concepts about which we need to capture and store data.
|
|
|
4.
|
An attribute is a descriptive property or
characteristic of an entity.
|
|
|
5.
|
A compound attribute is one that actually consists
of other attributes that are logically grouped together.
|
|
|
6.
|
The data type of an attribute defines what type of
data can be stored in that attribute.
|
|
|
7.
|
The domain of an attribute defines what values an
attribute can legitimately take on.
|
|
|
8.
|
A key is an attribute or group of attributes that
assumes a unique value for each entity instance. It is sometimes called the domain of the
attribute.
|
|
|
9.
|
A concatenated key is a group of attributes that
uniquely identifies an instance of an entity.
|
|
|
10.
|
A primary key is that candidate key that will most
commonly be used to uniquely identify a single entity instance.
|
|
|
11.
|
An alternate key is also known as a secondary
key.
|
|
|
12.
|
A relationship may represent an event that links
the entities or merely a physical affinity that exists between the entities.
|
|
|
13.
|
Because all relationships are bi-directional in an
entity relationship diagram, cardinality must be defined in both directions for every
relationship.
|
|
|
14.
|
The relationship between a student entity and a
curriculum entity would be classified as recursive.
|
|
|
15.
|
In a one-to-many relationship, the parent is the
entity on the "one" side.
|
|
|
16.
|
A foreign key in a child entity always matches the
primary key in the parent entity.
|
|
|
17.
|
Identifying relationships are those in which the
parent entity contributes its primary key to become part of the primary key of the child
entity.
|
|
|
18.
|
A many-to-many relationship is one in which many
entities are associated with other attributes of a different entity.
|
|
|
19.
|
An enterprise data model typically identifies and
defines only the most complex entities used by the enterprise.
|
|
|
20.
|
During systems design, the logical data model will
be transformed into a physical data model.
|
|
|
21.
|
Another name for the logical data model is the
database schema.
|
|
|
22.
|
The value of a key can change over the lifetime of
each entity instance.
|
|
|
23.
|
The value of a key can be null.
|
|
|
24.
|
Controls must be installed to ensure that the value
of a key is valid.
|
|
|
25.
|
Alphabetic codes use finite combinations of letters
(and possibly numbers) to describe entity instances.
|
|
|
26.
|
Hierarchical codes provide a top-down
interpretation for an entity instance by factoring an item into its group, subgroup and so
forth.
|
|
|
27.
|
Many organizations have naming standards and
approved abbreviations for data attributes.
|
|
|
28.
|
A good data model is essentially
nonredundant.
|
|
|
29.
|
Many nonspecific relationships can be resolved into
two one-to-many relationships using an associative entity.
|
Multiple Choice
Identify the
choice that best completes the statement or answers the question.
|
|
|
30.
|
Which of the following is a category of
entities?
a. | person | b. | place | c. | object | d. | concept | e. | all of
these |
|
|
|
31.
|
A descriptive property or characteristic of an
entity is:
a. | a domain | b. | an attribute | c. | an entity
instance | d. | an entity existence | e. | none of these |
|
|
|
32.
|
A data type:
a. | defines what type of data can be stored in an
attribute. | b. | could be text,
number, date, time, yes/no, value set or image. | c. | consists of
compound attributes. | d. | both (A) and
(B). | e. | none of these |
|
|
|
33.
|
An attribute or group of attributes that assumes a
unique value for each entity instance is a:
a. | domain | b. | key | c. | default
value | d. | data type | e. | none of these |
|
|
|
34.
|
If an employee entity had both an EmployeeID
attribute and a Social Security Number attribute, the one that was not used as the primary key would
be called a(n):
a. | entity key | b. | concatenated key | c. | alternate
key | d. | candidate key | e. | all of these |
|
|
|
35.
|
A ternary relationship is:
a. | recursive | b. | reflexive | c. | between three
entities | d. | is not possible in data
modeling | e. | none of these |
|
|
|
36.
|
When a parent entity contributes its primary key to
become part of the primary key of the child entity, the relationship is known as:
a. | primary | b. | associative | c. | nonidentifying | d. | identifying | e. | none of
these |
|
|
|
37.
|
A technique wherein attributes that are common to
several types of an entity are grouped into their own entity called a supertype is
called:
a. | normalization | b. | generalization | c. | concatenation | d. | compound data
type | e. | none of these |
|
|
|
38.
|
The data model for a single information system is
usually called:
a. | the enterprise data model | b. | the logical data model | c. | the physical data
model | d. | the application data model | e. | none of these |
|
|
|
39.
|
A key value whose structure communicates data about
an entity instance:
a. | is known as an intelligent
key. | b. | should be avoided (suggested by the authors of your
book). | c. | is randomly assigned. | d. | can only use alphabetic codes. | e. | all of these |
|
|
|
40.
|
A code that uses blocks of numbers that are divided
into groups that have some business meaning is known as a:
a. | serial code | b. | hierarchical code | c. | significant
position code | d. | block
code | e. | none of these |
|
|
|
41.
|
The process that prepares a data model for
implementation as a simple, nonredundant, flexible and adaptable database is known as:
a. | process analysis | b. | requirements analysis | c. | data
analysis | d. | generalization | e. | none of these |
|
|
|
42.
|
Which normal form deals with repeating
attributes?
a. | 1NF | b. | 2NF | c. | 3NF | d. | all of
these | e. | none of these |
|
|
|
43.
|
In the relationship between US cities and US
states, the state entity would be:
a. | the child | b. | the parent | c. | nonspecific | d. | subtype | e. | supertype |
|
|
|
44.
|
When a nonkey attribute is dependent on another
nonkey attribute (other than by derivation) is known as:
a. | an associative dependency | b. | a concatenation dependency | c. | a transitive dependency | d. | a derived
dependency | e. | none of
these |
|
|
|
45.
|
An entity relationship diagram:
a. | is used in data modeling. | b. | depicts data in terms of entities and
relationships. | c. | identifies the
cardinality of a relationship. | d. | makes clear the
degree of a relationship. | e. | all of
these |
|
|
|
46.
|
Every student resides in 0 or 1 dorm. This is an
example of:A) domain
a. | default | c. | cardinality | b. | degree | d. | nonspecific
relationship |
|
Completion
Complete each
statement.
|
|
|
47.
|
The three properties of an attribute are:
___________________________, _______________________, and
_____________________________.
|
|
|
48.
|
Every entity must have
__________________________.
|
|
|
49.
|
All relationships are implicitly
_____________________________.
|
|
|
50.
|
A(n) _______________________________ relationship
is where a relationship exists between different instances of the same entity.
|
|
|
51.
|
A(n) _____________________________ relationship is
one between three different entities.
|
|
|
52.
|
________________________________ relationships are
those in which each of the participating entities has its own independent primary key.
|
|
|
53.
|
A ___________________________ is an entity whose
instances inherit some common attributes from an entity supertype and then add other attributes that
are unique to its instance.
|
|
|
54.
|
Another name for an alternate key is
______________________________ key.
|
|
|
55.
|
_________________________ is data about the
business's data.
|
|
|
56.
|
In ________________________ codes , each digit or
group of digits describes a measurable or identifiable characteristic of the entity
instance.
|
|
|
57.
|
_________________________ is a data analysis
technique that organizes data attributes such that they are grouped to form nonredundant, stable,
flexible, and adaptive entities.
|
|
|
58.
|
Data modeling is sometimes called
__________________________________ because a data model is usually implemented as a
database.
|
|
|
59.
|
A(n) _________________________ is something that
the business needs to store data.
|
|
|
60.
|
The entity on the "many" side of a
one-to-many relationship is called the _____________.
|