Chapter 7 Logical Database Design
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Last Update: November 17, 2011 — 9PM
Chapter 7: Logical Database Design
Multiple Choice
1. The goal of logical database design is ____.
a. to fine tune the database’s physical database design
b. to convert databases from a hierarchical or network structure to a relational
structure
c. to improve performance
d. to create well-structured tables that properly reflect the company’s business
environment
e. None of the above.
2. Which of the following are logical database design techniques?
a. Conversion of E-R diagrams to relational tables.
b. Data normalization.
c. System development.
d. a & b above
e. All of the above.
3. Logical database design ____.
a. is a part of physical database design
b. includes physical database design as one of its elements
c. results in a set of database tables that contain redundant data
d. results in a set of database tables that are optimized for performance
e. None of the above.
4. Placing the unique identifier of one database table in another existing or new table in
the database ____.
a. creates a foreign key
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b. may indicate the creation of a one-to-many binary relationship
c. may indicate the creation of a many-to-many binary relationship
d. All of the above.
e. None of the above.
5. Converting a one-to-one binary relationship into a relational database from an E-R
diagram ____.
a. can be done by placing the unique identifier of one of the tables into the other
b. can be done by creating a single table that combines the attributes of the two
entities
c. requires the creation of an additional table beyond the two that represent the two
entities in the relationship
d. a & b above
e. a & c above
6. Converting a one-to-many binary relationship into a relational database from an E–R
diagram ____.
a. can be done by placing the unique identifier of one of the tables into the other
b. can be done by creating a single table that combines the attributes of the two
entities
c. requires the creation of an additional table beyond the two that represent the two
entities in the relationship
d. a & b above
e. a & c above
7. Converting a many-to-many binary relationship into a relational database from an E-
R diagram ____.
a. can be done by placing the unique identifier of one of the tables into the other
b. can be done by creating a single table that combines the attributes of the two
entities
c. requires the creation of an additional table beyond the two that represent the two
entities in the relationship
d. a & b above
e. a & c above
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8. Converting a one-to-one unary relationship into a relational database from an E-R
diagram ____.
a. can be done by adding another copy of the unique identifier of the single entity’s
table into the same table with a different attribute name
b. can be done by splitting the attributes of the single entity into two tables, each
with its own copy of the unique identifier
c. requires the creation of an additional table beyond the one that represents the
single entity in the relationship
d. a & b above
e. a & c above
9. Converting a one-to-many unary relationship into a relational database from an E–R
diagram ____.
a. can be done by adding another copy of the unique identifier of the single entity’s
table into the same table with a different attribute name
b. can be done by splitting the attributes of the single entity into two tables, each
with its own copy of the unique identifier
c. requires the creation of an additional table beyond the one that represents the
single entity in the relationship
d. a & b above
e. a & c above
10. Converting a many-to-many unary relationship into a relational database from an E-R
diagram ____.
a. can be done by adding another copy of the unique identifier of the single entity’s
table into the same table with a different attribute name
b. can be done by splitting the attributes of the single entity into two tables, each
with its own copy of the unique identifier
c. requires the creation of an additional table beyond the one that represents the
single entity in the relationship
d. a & b above
e. a & c above
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11. Converting a ternary relationship into a relational database from an E-R diagram
____.
a. can be done by placing the unique identifier of one of the tables into the others
b. can be done by creating a single table that combines the attributes of the three
entities
c. requires the creation of an additional table beyond the three that represent the
three entities in the relationship
d. a & b above
e. a & c above
12. Data normalization ____.
a. precedes physical database design
b. follows physical database design
c. is a physical database design technique
d. includes the creation of indexes among its steps
e. uses as its main technique the conversion of E-R diagrams into relational tables
13. Data normalization ____.
a. is capable of creating relational tables that are free of data redundancy
b. is a logical database design technique
c. can be used to check the accuracy of the E-R diagrams to relational tables
conversion technique
d. All of the above.
e. None of the above.
14. The term that describes a non-key field of a relational table being dependent on only
part of the table’s key is ____.
a. full functional dependency
b. determinant
c. partial functional dependency
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d. transitive dependency
e. minimum dependency
15. The term that describes one non-key field of a table being dependent on another non-
key field of the table is ____.
a. full functional dependency
b. determinant
c. partial functional dependency
d. transitive dependency
e. minimum dependency
16. The term that describes an attribute whose value establishes the value of another
attribute is ____.
a. full functional dependency
b. determinant
c. partial functional dependency
d. transitive dependency
e. minimum dependency
17. Data in ____ has only a single attribute value in every attribute position.
a. first normal form
b. second normal form
c. third normal form
d. All of the above.
e. None of the above.
18. Data in ____ cannot have transitive dependencies.
a. first normal form
b. second normal form
c. third normal form
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d. All of the above.
e. None of the above.
19. Data in ____ cannot have partial functional dependencies but can have transitive
dependencies.
a. first normal form
b. second normal form
c. third normal form
d. All of the above.
e. None of the above.
20. A relational table in first normal form ____.
a. is also in second normal form
b. is also in third normal form
c. has no transitive dependencies
d. has no determinants
e. None of the above.
21. A relational table in second normal form ____.
a. is also in first normal form
b. is also in third normal form
c. has no transitive dependencies
d. has no determinants
e. has no functional dependencies
22. A relational table in third normal form ____.
a. is also in first normal form
b. is also in second normal form
c. has no transitive dependencies
d. All of the above.
Chapter 7 Logical Database Design
e. None of the above.
23. In third normal form, the exception to the rule that a non-key attribute cannot define
another non-key attribute is ____.
a. if the defining attribute is a candidate key
b. if the defined attribute is a candidate key
c. if the defining attribute is a foreign key
d. if the defined attribute is a foreign key
e. None of the above.
24. Which of the following regarding checking the results of one logical database design
technique with another is true?
a. Neither the E-R diagram conversion process result nor the data normalization
result can be checked with the other process.
b. The E-R diagram conversion process result and the data normalization result can
each be checked with the other process.
c. The result of data normalization is checked with the E-R diagram conversion
process.
d. The result of the E-R diagram conversion process is checked with data
normalization.
e. None of the above.
True/False
1. Logical database design is the process of modifying the physical database design to
improve performance.
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2. Physical database design is the process of modifying the logical database design to
improve performance.
3. The two major logical database design techniques are conversion of E-R diagrams to
relational tables and data normalization.
4. A simple entity box in an E-R diagram is converted into a relation table in a relational
database.
5. A one-to-one binary relationship in an E-R diagram can be converted into either one
or two tables in a relational database.
6. Converting a one-to-one binary relationship in an E-R diagram into a single table in a
relational database introduces data redundancy.
7. In converting a one-to-one binary relationship in an E-R diagram into two relational
tables, the rule is that the unique identifier of the entity on the “many side” of the one–
to-many relationship is placed as a foreign key in the table representing the entity on
the “one side.”
8. A many-to-many binary relationship in an E-R diagram requires the creation of a total
of three tables in a relational database.
Chapter 7 Logical Database Design
9. A one-to-one unary relationship in an E-R diagram requires the creation of a total of
three tables in a relational database.
10. A one-to-many unary relationship in an E-R diagram can be handled within a single
table in the conversion to a relational database design.
11. A many-to–many unary relationship in an E-R diagram requires the creation of a total
of three tables in a relational database.
12. A ternary relationship in an E-R diagram requires the creation of a total of three
tables in a relational database.
13. Data normalization is a methodology for organizing attributes into tables so that
redundancy among the non-key attributes is eliminated.
14. A functional dependency is a means of expressing that the value of one particular
attribute is associated with several values of another attribute.
15. The input to the data normalization process is a list of the attributes in the database
and a list of the functional dependencies among them.
16. In data normalization terminology, an attribute is functionally dependent on its
determinant.
17. The determinant of an attribute must always be a single attribute.
18. The data normalization process is known as a “composition process.”
19. In the data normalization process, the database’s attributes are subdivided into groups
that will eventually form the database’s tables.
20. A group of tables is said to be in a particular normal form if every table in the group
is in that normal form.
21. The data normalization process is progressive. If a group of tables is in second
normal form it is also in third normal form.
22. Multivalued attributes are not permitted in unnormalized data.
23. In first normal form tables every attribute value is atomic, that is no attribute is multi-
valued.
24. First normal form tables are free of data redundancy.
25. In first normal form a single, generally multi-attribute, key is chosen that defines or
determines all of the other attributes.
26. A partial functional dependency occurs when an attribute of a relational table is
dependent on only part of the table’s key.
27. Converting from first to second normal form involves subdividing tables to remove
partial functional dependencies.
28. A transitive dependency occurs when a nonkey attribute determines another nonkey
attribute.