Chapter 6 Flashcards
A table that displays data redundancies yields _____.
a) fewer attributes
b) anomalies
c) consistencies
d) more entities
b) anomalies
BCNF can be violated only if the table contains more than one _____ key.
a) candidate
b) secondary
c) primary
d) foreign
a) candidate
An example of denormalization is using a _____ denormalized table to hold report data. This is required when creating a tabular report in which the columns represent data that are stored in the table as rows.
a) temporary
b) 3NF
c) component
d) transitive
a) temporary
The combination of normalization and ER modeling yields a useful ERD, whose entities can be translated into appropriate relationship structures.
A) true
B) false
B) false
The objective of normalization is to ensure that each table conforms to the concept of well-formed relations.
A) true
B) false
A) true
To generate a surrogate key, Microsoft Access uses a(n) _____ data type.
a) sequence
b) AutoNumber
c) identity
d) character
b) AutoNumber
Atomic attributes are attributes that can be further subdivided.
A) true
B) false
B) false
Attribute A _____ attribute B if all of the rows in the table that agree in value for attribute A also agree in value for attribute B.
a) owns
b) determines
c) derives from
d) controls
b) determines
A dependency of one nonprime attribute on another nonprime attribute is a partial dependency.
A) true
B) false
B) false
Normalization purity is often easy to sustain in the modern database environment.
A) true
B) false
B) false
An attribute that is part of a key is known as a(n) _____ attribute.
a) nonprime
b) prime
c) entity
d) important
b) prime
For most business transactional databases, we should normalize relations into _____.
a) 1NF
b) 2NF
c) 3NF
d) 6NF
c) 3NF
A table is in fourth normal form if it is in third normal form and has no independent multivalued dependencies.
A) true
B) false
A) true
Repeating groups must be eliminated by ensuring that each row defines a single entity.
A) true
B) false
A) true
Dependency diagrams are very helpful in getting a bird’s-eye view of all the relationships among a table’s attributes.
A) true
B) false
A) true
From a structural point of view, 2NF is better than _____.
a) BCNF
b) 3NF
c) 4NF
d) 1NF
d) 1NF
A table is in BCNF if every determinant in the table is a foreign key.
A) true
B) false
B) false
An atomic attribute _____.
a) displays multiplicity
b) cannot exist in a relational table
c) is always chosen to be a foreign key
d) cannot be further subdivided
d) cannot be further subdivided
Normalization is a very important database design ingredient, and the highest level is always the most desirable.
A) true
B) false
B) false
Normalization represents a micro view of the entities within the ERD.
A) true
B) false
A) true
