Modern Database Management, 11e (Hoffer/Ramesh/Topi) Chapter 4 Logical Database
Design and the Relational Model
1) A form of database
specification that indicates all the parameters for data storage
that are then input to database implementation is:
A)
logical.
B)
physical.
C)
schematic.
D)
conceptual. Answer: B
Diff: 1 Page Ref:153
Topic: An Overview of Part Three AACSB: Use of Information Technology
2) Physical database
design decisions must be made carefully because
of impacts on:
A)
data accessibility.
B)
response times.
C)
security.
D)
all of the above.
Answer: D
Diff: 1 Page Ref:154
Topic:
An Overview of Part
Three
AACSB:
Analytic Skills, Use of Information Technology
3) The relational data model consists
of which components?
A)
Data structure
B)
Data manipulation
C)
Data integrity
D)
All of the above
Answer: D
Diff: 1 Page Ref:156
Topic: The Relational Data Model AACSB: Use of Information Technology
4) A two-dimensional table of data is called a:
A)
group.
B)
set.
C)
declaration.
D)
relation.
Answer: D
Diff: 1 Page Ref:157
Topic:
The Relational Data Model
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Relational Data Structure
5) is a component of the relational data model included to specify
business rules to maintain the integrity of data when
they are manipulated.
A)
Business rule constraint
B)
Data integrity
C)
Business integrity
D)
Data structure
Answer: B
Diff: 1 Page Ref:156
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Basic
Definitions
6) An attribute (or attributes) that uniquely identifies each row in a relation
is called a:
A)
column.
B)
foreign field.
C)
primary key.
D)
duplicate key.
Answer: C
Diff: 1 Page Ref:157
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Relational
Keys
7) An attribute
in a relation of a database that serves as the primary
key of another relation in the
same database is called a:
A)
link attribute.
B)
link key.
C)
foreign key.
D)
foreign attribute.
Answer: C
Diff: 1 Page Ref:158
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Relational
Keys
8) A primary
key that consists of more
than one attribute
is called a:
A)
foreign key.
B) composite key.
C)
multivalued key.
D)
cardinal key.
Answer: B
Diff: 2 Page Ref:157
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Relational
Keys
9) Which of the
following are properties of relations?
A)
Each attribute has a unique name.
B)
No two rows in
a relation are identical.
C)
There are no multivalued attributes in a relation.
D)
All of the above.
Answer: D
Diff: 1 Page Ref:158
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Properties
of Relations
10) In the figure below, the primary key for "Order Line"
is which type of key?
A) Composite
B)
Foreign
C)
Standard
D)
Grouped Answer: A
Diff: 2 Page Ref:157
Topic:
The Relational Data Model
AACSB:
Analytic Skills, Use of Information Technology
11) Which of the following
is NOT a reason to create an instance of a relational schema with sample
data?
A)
Sample data
can be used to improve user communications.
B)
Sample data can be used for prototype
generation.
C)
Sample data can reverse database
implementation errors.
D)
Sample data provide
a convenient way to check the accuracy
of your design. Answer: C
Diff: 2 Page Ref:160
Topic:
The Relational Data Model
AACSB:
Analytic Skills, Use of Information Technology
12) The entity integrity rule states that:
A)
no primary key attribute
can be null.
B)
referential integrity must be
maintained across all entities.
C)
each entity must have
a primary key.
D)
a primary key must have only one attribute.
Answer: A
Diff:
2 Page Ref:160 Topic: Integrity Constraints
AACSB: Use of Information Technology Subtopic: Domain
Constraints
13) A domain definition consists of the following components EXCEPT:
A)
domain name.
B)
data type.
C)
integrity constraints.
D)
size. Answer: C
Diff: 2 Page Ref:160
Topic: Integrity Constraints
AACSB: Use of Information Technology Subtopic: Domain
Constraints
14) The states that no primary
key attribute may be null.
A)
referential integrity constraint
B)
entity integrity rule
C)
partial specialization rule
D)
range domain rule Answer: B
Diff: 2 Page Ref:161
Topic:
The Relational Data Model
AACSB: Analytic
Skills, Reflective Thinking Subtopic: Entity Integrity
15) A rule that states that each foreign key value
must match a primary key value in
the other relation is called the:
A)
referential integrity constraint.
B)
key match rule.
C)
entity key group rule.
D)
foreign/primary match rule. Answer: A
Diff:
1 Page Ref:162 Topic: Integrity Constraints
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Referential Integrity
16) In the SQL language, the statement is used to make table
definitions.
A)
create session
B)
create table
C)
create index
D)
select Answer: B
Diff:
2 Page Ref:163 Topic: Integrity Constraints
AACSB: Use of Information Technology Subtopic: Creating
Relational Tables
17) Which of the following
are anomalies that can
be caused by redundancies in tables?
A)
Insertion
B)
Deletion
C)
Modification
D)
All of the above
Answer: D
Diff: 1 Page Ref:164,
165 Topic: Integrity
Constraints
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Well-Structured Relations
18) A relation that contains minimal
redundancy and allows easy use is considered
to be:
A)
clean.
B)
simple.
C)
complex.
D)
well-structured.
Answer: D
Diff: 1 Page Ref:164
Topic: Integrity Constraints
AACSB: Use of Information Technology Subtopic: Well-Structured
Relations
19) Understanding the steps involved
in transforming EER diagrams into relations is important
because:
A)
you must be able to check the output of a CASE tool.
B)
there are rarely
legitimate alternatives from which to
choose.
C)
CASE tools can model
any situation.
D)
none of the above.
Answer: A
Diff: 2 Page Ref:165
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
20) A nonkey
attribute is also called a(n):
A)
column.
B)
unimportant datum.
C)
descriptor.
D)
address. Answer: C
Diff: 2 Page Ref:167
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Multivalued Attributes
21) When a regular
entity type contains a multivalued attribute, one must:
A)
create a single
relation with multiple
lines for each instance of the multivalued attribute.
B)
create two new relations, one containing the multivalued attribute.
C)
create two new relations, both containing the multivalued attribute.
D)
none of the above.
Answer: B
Diff: 2 Page Ref:167
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Multivalued Attributes
22) In the figure below,
what type of relationship do the relations depict?
A)
Strong entity/weak entity
B)
Multivalued
C)
Composite foreign key
D)
One-to-many Answer: A
Diff: 2 Page Ref:167,168
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 2: Map Weak Entities
23) In the figure below,
what type of relationship do the relations depict?
A)
Strong entity/weak entity
B)
One-to-many
C)
Ternary
D)
Many-to-many Answer: B
Diff: 2 Page Ref:169,170
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 3: Map Binary
Relationships
24) In the figure below, what type of relationship is depicted?
A)
One-to-one
B)
Unary
C)
One-to-many
D)
Many-to-many Answer: D
Diff: 2 Page Ref:170
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Map Binary Many-to-Many
Relationships
25) In the figure below, what type of
key is depicted?
A)
Primary
B)
Recursive primary
C)
Composite
D)
Recursive foreign
Answer: D
Diff: 2 Page Ref:173
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Unary One-to-Many
Relationships
26) Referring to the
figure below, , which of the
following is NOT true?
A)
A component is part of an item.
B)
A component
is always used in only one item.
C)
A component
can be part of an item.
D)
A component may be used in many items.
Answer: B
Diff: 3 Page Ref:173,174
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 5: Map Unary
Relationships
27) The figure below, is an example of mapping which type of relationship?
A)
First
B)
Second
C)
Unary
D)
Ternary Answer: D
Diff: 3 Page Ref:175
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Mapping Ternary (and n-ary)
Relationships
28) All of the
following are the main goals of normalization EXCEPT:
A)
minimize data redundancy
B)
simplify the enforcement of referential integrity
C)
maximize storage space
D)
make it easier
to maintain data Answer: C
Diff: 3 Page Ref:179
Topic:
Introduction to Normalization
AACSB:
Analytic Skills, Use of Information Technology
29) When all multivalued attributes have been removed
from a relation, it is said to be in:
A)
first normal form.
B)
second normal form.
C)
Boyce-Codd normal form.
D)
third normal form. Answer: A
Diff: 2 Page Ref:179
Topic:
Introduction to Normalization
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Steps in Normalization
30) The normal
form which removes
any remaining functional dependencies because
there was more than one
primary key for the same nonkeys is called:
A)
Fifth normal form.
B)
Fourth normal form.
C)
Boyce-Codd normal form.
D)
Sixth normal form. Answer: C
Diff: 2 Page Ref:179
Topic:
Introduction to Normalization
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Steps in Normalization
31) The normal form which deals with multivalued dependencies is called:
A)
Fifth normal form.
B)
Fourth normal form.
C)
Boyce-Codd normal form.
D)
Sixth normal form. Answer: B
Diff: 2 Page Ref:179
Topic:
Introduction to Normalization
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Steps in Normalization
32) A relation
that contains no multivalued attributes, and has nonkey attributes
solely dependent on the primary key,
but contains transitive dependencies is in which normal form?
A)
First
B)
Second
C)
Third
D)
Fourth Answer: B
Diff: 2 Page Ref:179
Topic:
Introduction to Normalization
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Steps in Normalization
33) A constraint between two attributes is called a(n):
A)
functional relation.
B)
attribute dependency.
C)
functional
dependency.
D)
functional relation constraint. Answer: C
Diff: 1 Page Ref:179
Topic: Introduction to Normalization AACSB: Use of Information Technology Subtopic: Functional Dependencies and Keys
34) A candidate
key must satisfy all of
the following conditions EXCEPT:
A)
the key must uniquely identify
the row.
B)
the key must
indicate the row's position in the table.
C)
the key must be
nonredundant.
D)
each nonkey attribute
is functionally dependent
upon it. Answer: B
Diff: 2 Page Ref:181
Topic: Introduction to Normalization
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Candidate Keys
35) The attribute on the left-hand side of the arrow
in a functional dependency is the:
A)
candidate key.
B)
Determinant.
C)
foreign key.
D)
primary key.
Answer: B
Diff: 2 Page Ref:181
Topic: Introduction to Normalization AACSB: Use of Information Technology Subtopic: Determinants
36) A functional dependency in which one or more nonkey
attributes are functionally dependent on part, but not all, of the primary key is called a dependency.
A)
partial key-based
B)
partial functional
C)
cross key
D)
merged relation
Answer: B
Diff: 1 Page Ref:185
Topic: Normalization Example: Pine Valley
Furniture Company AACSB: Analytic Skills, Use of Information
Technology Subtopic: Step 2: Convert
to Second Normal Form
37) A functional dependency between two or more nonkey attributes is called a:
A)
partial functional dependency.
B)
partial nonkey dependency.
C)
transitive dependency.
D)
partial transitive dependency. Answer: C
Diff: 1 Page Ref:186
Topic: Normalization Example: Pine Valley
Furniture Company AACSB: Analytic Skills, Use of Information
Technology Subtopic: Step 3: Convert
to Third Normal Form
38) Which of the following anomalies result from a transitive dependency?
A)
Insertion
B)
Modification
C)
Deletion
D)
All of the above
Answer: D
Diff: 1 Page Ref:186
Topic: Normalization Example: Pine Valley
Furniture Company AACSB: Analytic Skills, Use of Information
Technology
39) An understanding of how to merge
relation is important because:
A)
there may be a need to merge relations on projects with subteams.
B)
different views may need to be integrated.
C)
new data
requirements may produce
new relations to be merged.
D)
all of the above.
Answer: D
Diff: 2 Page Ref:188
Topic: Merging Relations
AACSB: Analytic
Skills, Use of Information Technology
40) Two or more
attributes having different
names but the same
meaning are called:
A) homonyms.
B)
aliases.
C)
synonyms.
D)
alternate attributes.
Answer: C
Diff: 1 Page Ref:189
Topic: Merging Relations
AACSB: Use of Information Technology Subtopic: Synonyms
41) An attribute that may have more than one meaning is called a(n):
A)
homonym.
B)
alias.
C)
double defined attribute.
D)
synonym. Answer: A
Diff: 1 Page Ref:189
Topic: Merging Relations
AACSB: Use of Information Technology Subtopic: Homonyms
42) An alternative name for an attribute is called a(n):
A)
synonym.
B)
alias.
C)
alternate attribute.
D)
related characteristic.
Answer: B
Diff: 1 Page Ref:189
Topic: Merging Relations
AACSB: Use of
Information Technology
43) A primary
key whose value is unique
across all relations is called a(n):
A)
global primary key.
B)
inter-table primary key.
C)
enterprise key.
D)
foreign global key. Answer: C
Diff: 1 Page Ref:191
Topic: A Final Step for Defining
Relational Keys AACSB: Use of Information Technology
44) Data structures include data organized in the form of tables with rows and columns. Answer: TRUE
Diff: 1 Page Ref:156
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Basic
Definitions
45) Data integrity
consists of powerful
operations to manipulate data stored in relations.
Answer: FALSE
Diff: 1 Page Ref:156
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Basic
Definitions
46) A composite key consists of only one attribute. Answer: FALSE
Diff: 1 Page Ref:157
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Relational
Keys
47) A primary
key is an attribute that uniquely
identifies each row in a relation. Answer: TRUE
Diff: 1 Page Ref:157
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Relational
Keys
48) A foreign key is a primary key of
a relation that also is a primary key in
another relation. Answer: FALSE
Diff: 2 Page Ref:158
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Relational
Keys
49) One property
of a relation is that each attribute within a relation
has a unique name. Answer: TRUE
Diff: 1 Page Ref:158
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Properties
of Relations
50) There can be multivalued attributes in a relation.
Answer: FALSE
Diff: 1 Page Ref:158
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Properties
of Relations
51) The columns
of a relation can be interchanged without
changing the meaning
or use of the relation.
Answer: TRUE
Diff: 1 Page Ref:158
Topic:
The Relational Data Model
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Properties of Relations
52) Unlike columns,
the rows of a relation
may not be interchanged and must be stored in one
sequence.
Answer: FALSE
Diff: 1 Page Ref:158
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Properties
of Relations
53) Sample data are useful
for developing prototype
applications and for testing queries. Answer: TRUE
Diff: 1 Page Ref:160
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Example
Database
54) The allowable range of values for a given attribute
is part of the domain
constraint. Answer: TRUE
Diff: 3 Page Ref:160
Topic: Integrity Constraints
AACSB: Use of Information Technology Subtopic: Domain
Constraints
55) All values that appear in a column
of a relation must be taken from the same domain.
Answer: TRUE
Diff: 1 Page Ref:160
Topic: Integrity Constraints
AACSB: Use of Information Technology Subtopic: Domain
Constraints
56) The entity
integrity rule states
that a primary key attribute
can be null. Answer: FALSE
Diff: 2 Page Ref:161 Topic: Entity Integrity
AACSB: Use of Information Technology
57) In the relational data model, associations between tables are defined through
the use of primary keys.
Answer: FALSE
Diff: 2 Page Ref:162
Topic: Integrity Constraints
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Referential Integrity
58) A referential integrity constraint is a rule that maintains
consistency among the rows of two
relations.
Answer: TRUE
Diff: 1 Page Ref:162
Topic: Integrity Constraints
AACSB: Use of Information Technology Subtopic: Referential
Integrity
59) A cascading
delete removes all records in other tables associated with the record
to be deleted.
Answer:
TRUE
Diff:
2 Page Ref:162 Topic: Integrity Constraints
AACSB: Use of Information Technology Subtopic: Referential
Integrity
60) The truncate
table statement in SQL creates
a new table. Answer: FALSE
Diff: 2 Page Ref:163
Topic: Integrity Constraints
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Creating Relational Tables
61) A well-structured relation contains minimal
redundancy and allows
users to manipulate the relation without errors or inconsistencies.
Answer:
TRUE
Diff: 1 Page Ref:164
Topic: Integrity Constraints
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Well-Structured Relations
62) An anomaly
is a type of flaw in the database server. Answer: FALSE
Diff: 2 Page Ref:164
Topic: Integrity Constraints
AACSB: Use of Information Technology Subtopic: Well-Structured
Relations
63) CASE tools can model
more complex data relationships, such as ternary
relationships. Answer: FALSE
Diff: 1 Page Ref:165
Topic: Transforming EER Diagrams into Relations
AACSB: Use of Information Technology
64) When a regular entity type contains a multivalued attribute, two relations are created.
Answer: TRUE
Diff: 2 Page Ref:167
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 1: Map Regular
Entities
65) When transforming a weak entity,
one should create one relation with both the attributes of the strong entity and the attributes
of the weak entity.
Answer:
FALSE
Diff: 2 Page Ref:167,168
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 2: Map Weak Entities
66) The primary
key of the many side migrates to the one side when transforming a one-to-many
relationship.
Answer:
FALSE
Diff: 2 Page Ref:169
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 3: Map Binary
Relationships
67) When transforming a one-to-one relationship, a new relation
is always created. Answer: FALSE
Diff: 2 Page Ref:170
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 3: Map Binary
Relationships
68) If an identifier is not assigned, the default primary
key for an associative relation
consists of the two primary
key attributes from the other two relations.
Answer:
TRUE
Diff: 2 Page Ref:171,172
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 4: Map Associative
Entities
69) An identifier assigned to an associative entity is also called a cross-relation key. Answer: FALSE
Diff: 2 Page Ref:172
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 4: Map Associative
Entities
70) In the figure below, each employee
has exactly one manager.
Answer: TRUE
Diff: 2 Page Ref:173.174
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 5: Map Unary
Relationships
71) When transforming a unary many-to-many relationship to relations, a recursive foreign
key is used.
Answer:
FALSE
Diff: 2 Page Ref:174
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 5: Map Unary
Relationships
72) The relational data model does at this time directly
support subtype/supertype relationships. Answer: FALSE
Diff: 1 Page Ref:176
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 7: Map
Supertype/Subtype Relationships
73) When normalizing, the goal is to decompose
relations with anomalies
to produce smaller, well-structured relations.
Answer:
TRUE
Diff: 2 Page Ref:179
Topic:
Introduction to Normalization
AACSB:
Analytic Skills, Use of Information Technology
74) A relation
in fifth normal
form may not contain any anomalies.
Answer: TRUE
Diff: 2 Page Ref:179
Topic:
Introduction to Normalization
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Steps in Normalization
75) A co-dependency is a constraint between two attributes or two sets of attributes. Answer: FALSE
Diff: 2 Page Ref:179
Topic: Introduction to Normalization AACSB: Use of Information Technology Subtopic: Functional Dependencies and Keys
76) A candidate key is an attribute, or combination of attributes, that uniquely identifies a row in a relation.
Answer: TRUE
Diff: 1 Page Ref:181
Topic: Introduction to Normalization AACSB: Use of Information Technology Subtopic: Candidate
Keys
77) A relation
is in first normal form if it has no more than one multivalued attribute. Answer: FALSE
Diff: 1 Page Ref:183
Topic: Normalization Example: Pine Valley
Furniture Company AACSB: Analytic Skills, Use of Information
Technology Subtopic: Step 1: Convert
to First Normal Form
78) A partial
functional dependency is a
functional dependency in which one or
more non-key attributes are functionally dependent on part (but not all)
of the primary key.
Answer:
TRUE
Diff: 1 Page Ref:185
Topic: Normalization Example: Pine Valley
Furniture Company AACSB: Analytic Skills, Use of Information
Technology Subtopic: Step 2: Convert
to Second Normal Form
79) A transversal dependency is a functional dependency between two or more nonkey attributes. Answer: FALSE
Diff: 1 Page Ref:186
Topic: Normalization Example: Pine Valley
Furniture Company AACSB: Analytic Skills, Use of Information
Technology Subtopic: Step 3: Convert
to Third Normal Form
80) Anomalies do not generally arise out of transitive dependencies. Answer: FALSE
Diff: 3 Page Ref:186
Topic: Normalization Example: Pine Valley
Furniture Company AACSB: Analytic Skills, Use of Information
Technology Subtopic: Step 3: Convert
to Third Normal Form
81) View integration is the process
of merging relations together. Answer: TRUE
Diff:
2 Page Ref:188 Topic: Merging
Relations
AACSB:
Analytic Skills, Use of Information Technology
82) A synonym
is an attribute that may have more than one meaning.
Answer: FALSE
Diff: 1 Page Ref:189
Topic: Merging Relations
AACSB: Use of Information Technology Subtopic: View
Integration Problems
83) When two or more attributes describe
the same characteristic of an entity,
they are synonyms.
Answer:
TRUE
Diff: 1 Page Ref:189
Topic: Merging Relations
AACSB: Use of Information Technology Subtopic: View
Integration Problems
84) An enterprise key is a foreign key whose value is unique
across all relations. Answer: FALSE
Diff: 1 Page Ref:191
Topic: A Final Step for Defining
Relational Keys AACSB: Use of Information Technology
85) A named,
two-dimensional table of data is called a(n) . Answer: relation
Diff: 1 Page Ref:157
Topic: The Relational Data Model AACSB: Use of Information Technology
86) A(n) is an attribute that uniquely identifies each row in a relation. Answer: primary key
Diff: 1 Page Ref:157
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Relational
Keys
87) A primary key
that consists of two or more attributes is called a(n) key. Answer: composite
Diff: 1 Page Ref:157
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Relational
Keys
88) An attribute
in a relation that serves as the primary key of another
relation in the same
database is called a(n) .
Answer: foreign key Diff:
1 Page Ref:158
Topic: The Relational Data Model AACSB: Use of Information Technology Subtopic: Relational
Keys
89) A(n) is a set of values
that may be assigned to an attribute. Answer: domain
Diff: 2 Page Ref:160
Topic: Integrity Constraints
AACSB: Use of Information Technology Subtopic: Domain
Constraints
90) The states that no primary
key attribute can be null. Answer: referential integrity constraint
Diff: 1 Page Ref:162
Topic: Integrity Constraints
AACSB: Use of Information Technology Subtopic: Referential
Integrity
91) A(n) is a rule that states that either each foreign key value must match a primary
key value in another relation or the foreign key value must be null.
Answer: referential integrity constraint Diff: 1 Page
Ref:162
Topic:
Integrity Constraints
AACSB: Use of Information Technology Subtopic: Referential
Integrity
92) A referential
integrity constraint states that each value
must match a(n) value in another relation or be blank.
Answer: foreign key; primary key Diff: 3 Page Ref:162
Topic:
Integrity Constraints
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Referential Integrity
93) When creating
tables using the CREATE TABLE statement, NOT NULL constrains an attribute from being assigned a(n) value.
Answer: null
Diff: 1 Page Ref:163
Topic: Integrity Constraints
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Creating Relational Tables
94) An error or
inconsistency resulting from redundancy in tables is called a(n) . Answer: anomaly
Diff: 1 Page Ref:164
Topic: Integrity Constraints
AACSB: Use of Information Technology Subtopic: Well-Structured
Relations
95) The first step in
transforming EER diagrams into relations is to . Answer: map regular entities
Diff: 1 Page Ref:166
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
96) Associative
entities are also called . Answer:
gerunds
Diff: 2 Page Ref:166
Topic: Transforming EER Diagrams into Relations
AACSB: Use of Information Technology
97) A weak entity
must always have a(n) that distinguishes the various occurrences of the weak entity for each owner entity instance.
Answer: partial identifier Diff: 3 Page Ref:168
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 2: Map Weak Entities
98) Sometimes,
associative entities have identifiers assigned
to them. Answer: surrogate
Diff: 2 Page Ref:171,172
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 4: Map Associative
Entities
99) A(n) is one that references the primary key values of the same relation.
Answer: recursive foreign key
Diff: 1 Page Ref:173
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
Subtopic: Step 5: Map Unary
Relationships
100) The process
of decomposing relations
with anomalies to create smaller,
well-structured relations is called .
Answer: normalization
Diff: 1 Page Ref:179
Topic:
Introduction to Normalization
AACSB:
Analytic Skills, Use of Information Technology
101) A(n) is a constraint between
two attributes or two sets of attributes. Answer: functional dependency
Diff: 1 Page Ref:179
Topic:
Introduction to Normalization
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Functional Dependencies and Keys
102) An attribute
or combination of attributes that uniquely identifies a row in a relation
is called a(n) .
Answer: candidate key Diff: 1 Page Ref:181
Topic:
Introduction to Normalization
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Functional Dependencies and Keys
103) A relation that
contains no multivalued attributes is in normal form. Answer: first
Diff: 1 Page Ref:183
Topic: Normalization Example: Pine Valley
Furniture Company AACSB: Analytic Skills, Use of Information
Technology Subtopic: Step 1: Convert
to First Normal Form
104) A is a functional dependency where one or more nonkey
attributes are functionally
dependent on part (but not all) of the primary key.
Answer: partial functional dependency Diff: 1 Page
Ref:185
Topic: Normalization Example: Pine Valley
Furniture Company AACSB: Analytic Skills, Use of Information
Technology Subtopic: Step 2: Convert
to Second Normal Form
105) A dependency is a
functional dependency between the
primary key and one or more nonkey attributes
that are dependent upon the primary key
via another nonkey attribute.
Answer: transitive
Diff: 1 Page Ref:186
Topic: Normalization Example: Pine Valley
Furniture Company AACSB: Analytic Skills, Use of Information
Technology Subtopic: Step 3: Convert
to Third Normal Form
106) An alternative
name for an attribute is a(n) . Answer:
alias
Diff: 1 Page Ref:189
Topic: Merging Relations
AACSB: Use of Information Technology Subtopic: View
Integration Problems
107) An attribute that
may have more than one meaning is called a(n) . Answer: homonym
Diff: 1 Page Ref:189
Topic: Merging Relations
AACSB: Use of Information Technology Subtopic: View
Integration Problems
108) A(n) is a primary key that is unique across
all relations. Answer: enterprise key
Diff: 1 Page Ref:191
Topic: A Final Step for Defining
Relational Keys AACSB: Use of Information Technology
109) Discuss the various relational keys.
Answer: A primary
key uniquely identifies each row of a relation (or
table). It can be either a single column or a composite of two or more columns,
which is called a composite key. A foreign key allows us to represent the relationship between
two tables. A foreign key in one table is generally a reference to a
primary key in another table.
Diff: 2 Page Ref:157,158
Topic: The Relational Data Model
AACSB: Reflective Thinking, Use of Information Technology Subtopic: Relational Keys
110) Discuss the properties of relations.
Answer: Each relation (or table) has a unique
name. An entry at the intersection of each row and
column is atomic and each row is unique. Each
attribute (or column) within a table has a unique name. The sequence of rows
and columns is insignificant.
Diff: 2 Page Ref:158
Topic:
The Relational Data Model
AACSB: Reflective Thinking, Use of Information Technology Subtopic: Properties of Relations
111) Discuss why it is a good idea to create an instance of your relational schema with sample data.
Answer:
Using sample data allows
you to test any assumptions that you
may have regarding the design. In addition, it provides a convenient way to
check the accuracy of your design and
helps to improve communication with users. A final benefit is that you will be
able to develop prototype applications and sample queries with the data.
Diff: 2 Page Ref:160
Topic:
The Relational Data Model
AACSB: Reflective Thinking, Use of Information Technology Subtopic: Sample Databases
112) Discuss the types of integrity constraints.
Answer: The three major types of integrity
constrains are domain constraints, entity integrity and referential integrity. A domain is a set of attributes
assigned to an attribute and consists of the domain name, data type, size and
allowable values. The entity integrity
rule is designed to ensure that every relation
has a primary key and that the
data values for the primary key are valid (in
particular, not null). The referential integrity constraint is a rule that
maintains consistency among the rows of two relations. If there is a foreign
key in one relation, there must be a
matching primary key in the other relation or the foreign key must be null.
Diff:
2 Page Ref:160-162 Topic: The Relational Data Model
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Integrity Constraints
113) What is an
anomaly and what are the three types of
anomalies?
Answer: An anomaly is an error or
inconsistency that may result when a user attempts to update a table that contains redundant
data. There are three types of anomalies. An insert anomaly occurs when a user
attempts to enter new information for part of a table. For example, if we
stored customer address with an
order. A deletion anomaly occurs when
the user wants to delete part of a record but also has to delete
related data. A modification anomaly
occurs when we have
to change the same data in multiple places.
Diff:
2 Page Ref:164,165 Topic: The Relational Data Model
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Well-Structured Relations
114) Discuss how you
would map a regular
entity to a relation.
Answer:
Each regular entity is transformed into a relation. There are a couple of things that need
to be done with some special types of
attributes. Composite attributes are broken down into their individual
components. Multivalued attributes are broken down into separate relations. For
example, if there was a multivalued skill attribute, this would become a skill
relation. Also, we ignore derived attributes.
Diff: 2 Page Ref:166,167
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills
Subtopic: Step 1: Map Regular
Entities
115) How do you convert weak entities to relations?
Answer:
A weak entity becomes a relation. However, since a
weak entity instance does not exist by itself, we must create a
relation with the primary key from the strong relation as the primary key as
well as the identifying attribute.
Diff: 2 Page Ref:167, 168
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills, Reflective
Thinking Subtopic: Step 2: Map Weak
Entities
116) Discuss when it is best to create
a surrogate key for an associative entity.
Answer: A surrogate key should be created when any of the following conditions hold: there is a
composite primary key, the natural primary key is inefficient (such as a long
name) or if the natural primary key is recycled. When you have an associative
entity, it is often best to use a surrogate key when you have more than two
relations that the associative entity is related to, since the primary key would
be a composite of the primary keys
of all entities related to the associative entity.
Diff: 2 Page Ref:169,
172
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills,
Use of Information Technology
117) Discuss the two possible
scenarios when mapping
an associative entity.
Answer:
There are two possible cases for associative entities. In one case, you
can have an identifier assigned. You would then use this as the primary key. The other case is where the
identifier is not assigned. In this case, you would use the primary
keys from the other two (or
more) relations that are related to the associative entity.
Diff: 2 Page Ref:171,172
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills
Subtopic: Step 4: Map Associative Entities
118) List and explain all of the normal forms.
Answer: There are six different normal forms, all
of which build upon each other. When a relation is in first normal form, all
repeating groups have been removed. Second normal form means that any partial
functional dependencies have been removed. A partial functional dependency occurs when a primary key is
a composite key and a non-key
attribute is dependent upon part of the key. A relation is in third normal form
when all transitive dependencies have been resolved. A transitive dependency
occurs when one non-key attribute is dependent upon another non-key
attribute. Boyce-Codd normal
form removes any further
dependencies that may result from anomalies. A relation is
in fourth normal form when any dependencies from multi- valued attributes have
been removed. Fifth normal form removes any further anomalies.
Diff: 2 Page Ref:179
Topic: Introduction to Normalization
AACSB: Analytic Skills
Subtopic: Steps in Normalization
119) Explain what a candidate key is and how it might
be used.
Answer:
A candidate key is an attribute or a combination of attributes that uniquely identifies a row in a relation. A candidate key must be nonredundant and
must also uniquely identify each row. When we look at functional dependencies
and candidate keys, we can always say that
a determinant is always a candidate key.
Diff: 2 Page Ref:181,182
Topic:
Functional Dependencies and Keys
AACSB: Analytic
Skills, Use of Information Technology Subtopic: Candidate Keys
120) Explain how subtype/supertype relationships are converted to
relations.
Answer:
When we have a supertype/subtype relationship, we need to assign one
entity for the supertype and one for
each subtype. The supertype has all attributes common to all subtypes as well as a primary key. Each subtype
relation has the primary key of the supertype as well as any
attributes that are specific to that subtype. Finally, we assign one or more
attributes to the supertype to function as subtype discriminators.
Diff: 1 Page Ref:176
Topic: Transforming EER Diagrams into Relations
AACSB: Analytic Skills
Subtopic: Step 7: Map Supertype/Subtype Relationships
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