Chapter 012 Databases
Multiple Choice Questions
1. Which view of data deals with how the data is actually formatted and located?
A. Physical view
B. Logical view
C. Information view
D. Technical view
2. A data field represents a(n)
A. character.
B. attribute.
C. record.
D. entity.
3. Collectively, a person's name, address, and age would be called a
A. character.
B. record.
C. field.
D. file.
4. A _____ in different tables can be used to integrate the data in a database.
A. table
B. key field
C. character
D. record
5. A credit card bill that is processed at one shot - say the end of the month - is an example of
A. batch processing.
B. group processing.
C. real-time processing.
D. consignment processing.
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Chapter 012 Databases
6. In _____, the user must wait for the computer to scan several records one at a time, until
the desired record is located.
A. sequential data access
B. direct access tape
C. coordinated storage
D. sequential access storage
7. Having several instances of the same data is called
A. data repetition.
B. data duplication.
C. data doubling.
D. data redundancy.
8. If Mr. Smith's bike has been sent to his new address, but the bill to his old one, it can most
likely be attributed to a
A. lack of data integrity.
B. lack of data maintenance.
C. lack of data redundancy.
D. lack of data administration.
9. Which of the following is not an advantage of using a database?
A. Security
B. Reliability
C. Sharing
D. Integrity
10. The data manipulation subsystem can use query-by-example as well as
A. SQL.
B. HTML.
C. XML.
D. VBA.
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Chapter 012 Databases
11. The feature of describing the entry field in a data dictionary form as 'text' is characteristic
of
A. data manipulation subsystem.
B. application generation subsystem.
C. data administration subsystem.
D. data definition subsystem.
12. The DBA can create user forms and menus using the
A. data administration subsystem.
B. DBMS engine.
C. data definition subsystem.
D. application generation subsystem.
13. A nationwide airline reservation system is an example of this type of database model.
A. Relational model
B. Hierarchical model
C. Multidimensional model
D. Object-oriented model
14. A network database can utilize ____, special connections between nodes that allow
multiple connections between records.
A. connectors
B. links
C. strings
D. pointers
15. This type of database is organized into many tables with common data items (key fields)
linking the tables to one another.
A. Hierarchical
B. Multidimensional
C. Relational
D. Network
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16. Which of the following is an advantage of using multidimensional databases?
A. Smaller hard disk usage
B. Network ability
C. Simpler relationships
D. Intuitive conceptualization
17. _____ databases store not only data but also instructions to manipulate the data.
A. Hierarchical
B. Network
C. Object-oriented
D. Multidimensional
18. In the object-oriented database model, this term is the equivalent to a field in a relational
model.
A. Entities
B. Classes
C. Methods
D. Attributes
19. The data and the DBMS are stored either on the user's hard-disk drive or on a LAN file
server in these databases.
A. Company databases
B. Individual databases
C. Commercial databases
D. Web databases
20. A common operational database is a type of
A. distributed database.
B. individual database.
C. shared database.
D. commercial database.
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Chapter 012 Databases
21. The combined information presented on a(n) _____ can be used to change the whole
merchandising strategy of a store.
A. commercial database
B. individual database
C. company database
D. distributed database
22. If all the data in a database is not physically located in one place, it would be a(n)
A. individual database.
B. Web database.
C. commercial database.
D. distributed database.
23. This commercial database offers news and information on legal, public records, and
business issues.
A. CSi
B. Dialog Information Services
C. Dow Jones Interactive Publishing
D. LexisNexis
24. Information collected by an organization from a variety of external and internal databases
is stored in special type of database called a
A. data warehouse.
B. commercial database.
C. company database.
D. company warehouse.
25. Access to these databases is offered to the public or selected outside individuals for a fee.
A. data warehouses
B. commercial databases
C. company databases
D. distributed databases
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Chapter 012 Databases
True / False Questions
26. Data typically consists of numbers, letters, and symbols.
True False
27. The logical view of data focuses on meanings and content of the data.
True False
28. A record is a collection of related tables.
True False
29. Database tables can be related or connected to other tables by common key fields.
True False
30. The ATM works on the principle of real-time processing.
True False
31. Data redundancy results due to lack of data integrity.
True False
32. In order to create, modify, and gain access to a database, special software called the
database management system is required.
True False
33. Querying the database and generating reports is assisted by the application generation
subsystem.
True False
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Chapter 012 Databases
34. Typically, database administrators are employed to interact with the database
administration subsystem.
True False
35. The logical arrangement of data in a database is called the database model.
True False
36. A hierarchical database uses many-to-many relationships.
True False
37. In a network database, a node can be traced down through different branches.
True False
38. The database in which data elements are stored in a manner that doesn't require an access
path down a hierarchy is called the object-oriented database.
True False
39. Relational database tables require a common data item or key field.
True False
40. In a network database, nodes have a many-to-many relationship.
True False
41. In an object-oriented database, attributes are specific instances of a class that can contain
both data and instructions to manipulate the data.
True False
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Chapter 012 Databases
42. A self-employed financial consultant would keep track of what work and how many hours
to charge each client by using a distributed database.
True False
43. The company database may be stored on a mainframe and managed by a database
administrator.
True False
44. A commercial database is generally an enormous database that an organization develops
to cover particular subjects.
True False
45. Individual databases are the foundation of management information systems.
True False
Fill in the Blank Questions
46. The most basic logical element of data is a _____.
________________________________________
47. A _____ represents a collection of attributes that describe an entity.
________________________________________
48. A record represents a collection of attributes that describe an _____.
________________________________________
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Chapter 012 Databases
49. A _____ is a collection of related records.
________________________________________
50. A bank credit card reflects _____ processing.
________________________________________
51. Traditionally, data is processed in one of two ways: batch processing and _____
processing.
________________________________________
52. In _____ access storage, the computer continues scanning for records until the desired
record is located.
________________________________________
53. The scenario wherein many files about the same person exist across different departments
within an organization is called _____.
________________________________________
54. The _____ or schema contains a description of the structure of data in the database.
________________________________________
55. The analysis tools associated with the data manipulation subsystem include _____ and
structure query languages (SQL).
________________________________________
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Chapter 012 Databases
56. The analysis tools associated with the _____ subsystem include query-by-example and
structure query languages (SQL).
________________________________________
57. The duties of a database administrator include the determining of which people have
access to what kinds of data in the database, referred to as _____ rights.
________________________________________
58. Each entry in a/an _____ database has one parent node, with the parent node having
several child nodes.
________________________________________
59. In a/an _____ database, the elements are thus related that any action on one element
immediately affects the elements related to the first.
________________________________________
60. In a network database, a node may be reached through more than one path with the help of
_____.
________________________________________
61. In a _____ database, a node may be reached through more than one path with the help of
pointers.
________________________________________
62. In the _____ database, data elements are stored in different tables, each of which consists
of rows and tables.
________________________________________
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Chapter 012 Databases
63. In the _____ database, complex relationships between data can be represented and
efficiently analyzed.
________________________________________
64. Object-oriented databases organize data using objects, classes, entities, attributes, and
_____.
________________________________________
65. Users of a/an _____ database have access through their microcomputers linked to local or
wide area networks.
________________________________________
66. _____ databases are the foundation for management information systems.
________________________________________
67. In a _____ database, not all the data in a database is physically located in one place.
________________________________________
68. Dialog Information Services is an example of a _____ database.
________________________________________
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Chapter 012 Databases
Essay Questions
69. Define the physical and logical views of data.
70. Explain the components of data organization.
71. What are the advantages of having databases?
72. List and describe the five basic DBMS subsystems.
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Chapter 012 Databases
73. Describe the structure and functionality of a hierarchical database.
74. How does a relational database differ from a hierarchical database?
75. Describe the workings of an object-oriented database.
76. What is the difference between the individual database and the company database?
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Chapter 012 Databases
77. Explain commercial databases with examples.
78. What are some measures that can be taken to ensure a database's security?
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Chapter 012 Databases Key
Multiple Choice Questions
1. (p. 340) Which view of data deals with how the data is actually formatted and located?
A. Physical view
B. Logical view
C. Information view
D. Technical view
The physical view focuses on the actual format and location of the data.
Difficulty: Easy
2. (p. 342) A data field represents a(n)
A. character.
B. attribute.
C. record.
D. entity.
A data field represents an attribute (description or characteristics) of some entity (person,
place, thing, or object).
Difficulty: Medium
3. (p. 342) Collectively, a person's name, address, and age would be called a
A. character.
B. record.
C. field.
D. file.
A record is a collection of related fields. A record represents a collection of attributes that
describe an entity.
Difficulty: Medium
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Chapter 012 Databases Key
4. (p. 342) A _____ in different tables can be used to integrate the data in a database.
A. table
B. key field
C. character
D. record
In a database, each record is uniquely identified by its key field. Key fields in different files
can be used to integrate the data in a database.
Difficulty: Medium
5. (p. 342) A credit card bill that is processed at one shot - say the end of the month - is an
example of
A. batch processing.
B. group processing.
C. real-time processing.
D. consignment processing.
In batch processing, data is collected over several hours, days, or even weeks. It is then
processed all at once as a "batch."
Difficulty: Medium
6. (p. 344) In _____, the user must wait for the computer to scan several records one at a time,
until the desired record is located.
A. sequential data access
B. direct access tape
C. coordinated storage
D. sequential access storage
In sequential access storage, by contrast, the user must wait for the computer to scan several
records one at a time. It continues scanning until the desired record is located.
Difficulty: Medium
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Chapter 012 Databases Key
7. (p. 344) Having several instances of the same data is called
A. data repetition.
B. data duplication.
C. data doubling.
D. data redundancy.
Data redundancy occurs when you have several instances of the same data stored in multiple
files.
Difficulty: Medium
8. (p. 344) If Mr. Smith's bike has been sent to his new address, but the bill to his old one, it can
most likely be attributed to a
A. lack of data integrity.
B. lack of data maintenance.
C. lack of data redundancy.
D. lack of data administration.
With data redundancy, if one or more files are overlooked, problems will likely result. This
situation results from a lack of data integrity.
Difficulty: Medium
9. (p. 344) Which of the following is not an advantage of using a database?
A. Security
B. Reliability
C. Sharing
D. Integrity
Advantages include sharing, security, less data redundancy, and data integrity.
Difficulty: Medium
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Chapter 012 Databases Key
10. (p. 346) The data manipulation subsystem can use query-by-example as well as
A. SQL.
B. HTML.
C. XML.
D. VBA.
Data manipulation subsystem provides tools like query-by-example and structured query
languages (SQL) for data maintenance and data analysis.
Difficulty: Easy
11. (p. 345) The feature of describing the entry field in a data dictionary form as 'text' is
characteristic of
A. data manipulation subsystem.
B. application generation subsystem.
C. data administration subsystem.
D. data definition subsystem.
The logical structure of the database is described by the data definition subsystem. It defines
the type of data for each field (text, numeric, time, graphic, audio, and video).
Difficulty: Hard
12. (p. 346) The DBA can create user forms and menus using the
A. data administration subsystem.
B. DBMS engine.
C. data definition subsystem.
D. application generation subsystem.
The application generation subsystem provides tools to enable this task.
Difficulty: Hard
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Chapter 012 Databases Key
13. (p. 347) A nationwide airline reservation system is an example of this type of database
model.
A. Relational model
B. Hierarchical model
C. Multidimensional model
D. Object-oriented model
A nationwide airline reservations system is an example of a hierarchical database model.
Difficulty: Medium
14. (p. 348) A network database can utilize ____, special connections between nodes that allow
multiple connections between records.
A. connectors
B. links
C. strings
D. pointers
Pointers are used to connect parent nodes and child nodes.
Difficulty: Hard
15. (p. 348) This type of database is organized into many tables with common data items (key
fields) linking the tables to one another.
A. Hierarchical
B. Multidimensional
C. Relational
D. Network
In the relational database model, there are no access paths down a hierarchy. Rather, the data
elements are stored in different tables, each of which consists of rows and columns.
Difficulty: Hard
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Chapter 012 Databases Key
16. (p. 349) Which of the following is an advantage of using multidimensional databases?
A. Smaller hard disk usage
B. Network ability
C. Simpler relationships
D. Intuitive conceptualization
Multidimensional databases and hyper cubes provide users with an intuitive model in which
complex data and relationships can be conceptualized.
Difficulty: Medium
17. (p. 349) _____ databases store not only data but also instructions to manipulate the data.
A. Hierarchical
B. Network
C. Object-oriented
D. Multidimensional
Object-oriented databases store the data and the instructions to manipulate the data.
Difficulty: Easy
18. (p. 350) In the object-oriented database model, this term is the equivalent to a field in a
relational model.
A. Entities
B. Classes
C. Methods
D. Attributes
Attributes are the description of entities. They are similar to fields.
Difficulty: Hard
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Chapter 012 Databases Key
19. (p. 351) The data and the DBMS are stored either on the user's hard-disk drive or on a LAN
file server in these databases.
A. Company databases
B. Individual databases
C. Commercial databases
D. Web databases
In an individual database, typically, the data and the DBMS are under the direct control of the
user. They are stored either on the user's hard-disk drive or on a LAN file server.
Difficulty: Hard
20. (p. 351) A common operational database is a type of
A. distributed database.
B. individual database.
C. shared database.
D. commercial database.
Company (shared) databases are of two types: common operational database and common
user database.
Difficulty: Easy
21. (p. 351) The combined information presented on a(n) _____ can be used to change the whole
merchandising strategy of a store.
A. commercial database
B. individual database
C. company database
D. distributed database
Company databases are the foundation for management information systems. This
information could be used to change the whole merchandising strategy of the store.
Difficulty: Hard
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Chapter 012 Databases Key
22. (p. 351) If all the data in a database is not physically located in one place, it would be a(n)
A. individual database.
B. Web database.
C. commercial database.
D. distributed database.
Many times the data in a company is stored not in just one location but in several locations.
The database, then, is a distributed database. That is, not all the data in a database is
physically located in one place.
Difficulty: Medium
23. (p. 352) This commercial database offers news and information on legal, public records, and
business issues.
A. CSi
B. Dialog Information Services
C. Dow Jones Interactive Publishing
D. LexisNexis
LexisNexis is an important commercial database that offers news and information on legal,
public records, and business issues.
Difficulty: Medium
24. (p. 353) Information collected by an organization from a variety of external and internal
databases is stored in special type of database called a
A. data warehouse.
B. commercial database.
C. company database.
D. company warehouse.
To support the needs of managers and other business professionals, many organizations
collect data from a variety of internal and external databases. This data is then stored in a
special type of database called a data warehouse.
Difficulty: Easy
12-22
Chapter 012 Databases Key
25. (p. 353) Access to these databases is offered to the public or selected outside individuals for
a fee.
A. data warehouses
B. commercial databases
C. company databases
D. distributed databases
A commercial database is generally an enormous database that an organization develops to
cover particular subjects. It offers access to this database for a fee.
Difficulty: Medium
True / False Questions
26. (p. 340) Data typically consists of numbers, letters, and symbols.
FALSE
Difficulty: Easy
27. (p. 340) The logical view of data focuses on meanings and content of the data.
TRUE
Difficulty: Easy
28. (p. 342) A record is a collection of related tables.
FALSE
Difficulty: Medium
29. (p. 342) Database tables can be related or connected to other tables by common key fields.
TRUE
Difficulty: Medium
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Chapter 012 Databases Key
30. (p. 342) The ATM works on the principle of real-time processing.
TRUE
Difficulty: Easy
31. (p. 344) Data redundancy results due to lack of data integrity.
FALSE
Difficulty: Hard
32. (p. 345) In order to create, modify, and gain access to a database, special software called the
database management system is required.
TRUE
Difficulty: Easy
33. (p. 346) Querying the database and generating reports is assisted by the application
generation subsystem.
FALSE
Difficulty: Medium
34. (p. 346) Typically, database administrators are employed to interact with the database
administration subsystem.
TRUE
Difficulty: Medium
35. (p. 347) The logical arrangement of data in a database is called the database model.
TRUE
Difficulty: Easy
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Chapter 012 Databases Key
36. (p. 347) A hierarchical database uses many-to-many relationships.
FALSE
Difficulty: Medium
37. (p. 348) In a network database, a node can be traced down through different branches.
TRUE
Difficulty: Medium
38. (p. 348) The database in which data elements are stored in a manner that doesn't require an
access path down a hierarchy is called the object-oriented database.
FALSE
Difficulty: Hard
39. (p. 348) Relational database tables require a common data item or key field.
TRUE
Difficulty: Medium
40. (p. 348) In a network database, nodes have a many-to-many relationship.
TRUE
Difficulty: Easy
41. (p. 350) In an object-oriented database, attributes are specific instances of a class that can
contain both data and instructions to manipulate the data.
FALSE
Difficulty: Hard
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Chapter 012 Databases Key
42. (p. 351) A self-employed financial consultant would keep track of what work and how many
hours to charge each client by using a distributed database.
FALSE
Difficulty: Hard
43. (p. 351) The company database may be stored on a mainframe and managed by a database
administrator.
TRUE
Difficulty: Medium
44. (p. 352) A commercial database is generally an enormous database that an organization
develops to cover particular subjects.
TRUE
Difficulty: Easy
45. (p. 351) Individual databases are the foundation of management information systems.
FALSE
Difficulty: Hard
Fill in the Blank Questions
46. (p. 342) The most basic logical element of data is a _____.
character
A character is the most basic logical data element. It is a single letter, number, or special
character, such as a punctuation mark, or a symbol, such as $.
Difficulty: Easy
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Chapter 012 Databases Key
47. (p. 342) A _____ represents a collection of attributes that describe an entity.
record
A record is a collection of related fields. A record represents a collection of attributes that
describe an entity.
Difficulty: Medium
48. (p. 342) A record represents a collection of attributes that describe an _____.
entity
A record is a collection of related fields. A record represents a collection of attributes that
describe an entity.
Difficulty: Medium
49. (p. 342) A _____ is a collection of related records.
table
A table is a collection of related records.
Difficulty: Easy
50. (p. 342) A bank credit card reflects _____ processing.
batch
In batch processing, data is collected over several hours, days, or even weeks. If you have a
bank credit card, your bill probably reflects batch processing.
Difficulty: Medium
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Chapter 012 Databases Key
51. (p. 342) Traditionally, data is processed in one of two ways: batch processing and _____
processing.
real-time
Batch and real-time processing have been used to handle common record-keeping activities
such as payroll and sales orders.
Difficulty: Medium
52. (p. 344) In _____ access storage, the computer continues scanning for records until the
desired record is located.
sequential
In sequential access storage, the user must wait for the computer to scan several records one at
a time. It continues scanning until the desired record is located.
Difficulty: Hard
53. (p. 344) The scenario wherein many files about the same person exist across different
departments within an organization is called _____.
data redundancy
Many organizations have multiple files on the same subject or person. This is called data
redundancy.
Difficulty: Medium
54. (p. 345) The _____ or schema contains a description of the structure of data in the database.
data dictionary
A data dictionary contains a description of the structure of data in the database.
Difficulty: Easy
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Chapter 012 Databases Key
55. (p. 346) The analysis tools associated with the data manipulation subsystem include _____
and structure query languages (SQL).
query-by-example
The data manipulation subsystem provides tools for maintaining and analyzing data. Specific
tools include query-by-example and specialized programming languages called structured
query languages (SQL).
Difficulty: Hard
56. (p. 345) The analysis tools associated with the _____ subsystem include query-by-example
and structure query languages (SQL).
data manipulation
The data manipulation subsystem provides tools for maintaining and analyzing data. Specific
tools include query-by-example and specialized programming languages called structured
query languages (SQL).
Difficulty: Hard
57. (p. 346) The duties of a database administrator include the determining of which people have
access to what kinds of data in the database, referred to as _____ rights.
processing
Database administrators interact with the data administration subsystem, and determine
processing rights or determining which people have access to what kinds of data in the
database.
Difficulty: Medium
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Chapter 012 Databases Key
58. (p. 347) Each entry in a/an _____ database has one parent node, with the parent node having
several child nodes.
hierarchical
In a hierarchical database, fields or records are structured in nodes. Nodes are points
connected like the branches of an upside-down tree. Each entry has one parent node, although
a parent may have several child nodes.
Difficulty: Easy
59. (p. 347) In a/an _____ database, the elements are thus related that any action on one element
immediately affects the elements related to the first.
hierarchical
The problem with a hierarchical database is that if one parent node is deleted, so are all the
subordinate child nodes.
Difficulty: Medium
60. (p. 348) In a network database, a node may be reached through more than one path with the
help of _____.
pointers
A network database is sometimes described as a many-to-many relationship. There are
additional connections–called pointers–between parent nodes and child nodes. Thus, a node
may be reached through more than one path.
Difficulty: Hard
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Chapter 012 Databases Key
61. (p. 348) In a _____ database, a node may be reached through more than one path with the
help of pointers.
network
A network database is sometimes described as a many-to-many relationship. There are
additional connections–called pointers–between parent nodes and child nodes. Thus, a node
may be reached through more than one path.
Difficulty: Hard
62. (p. 348) In the _____ database, data elements are stored in different tables, each of which
consists of rows and tables.
relational
In a relational database, there are no access paths down a hierarchy. Rather, the data elements
are stored in different tables, each of which consists of rows and columns.
Difficulty: Medium
63. (p. 349) In the _____ database, complex relationships between data can be represented and
efficiently analyzed.
multidimensional
Each side of the cube in a multidimensional database is considered a dimension of the data. In
this way, complex relationships between data can be represented and efficiently analyzed.
Difficulty: Medium
64. (p. 349) Object-oriented databases organize data using objects, classes, entities, attributes,
and _____.
methods
Object-oriented databases organize data using objects, classes, entities, attributes, and
methods.
Difficulty: Easy
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Chapter 012 Databases Key
65. (p. 351) Users of a/an _____ database have access through their microcomputers linked to
local or wide area networks.
company
Users throughout the company have access to the company database through their
microcomputers linked to local area networks or wide area networks.
Difficulty: Hard
66. (p. 351) _____ databases are the foundation for management information systems.
Company
Company databases are the foundation for management information systems.
Difficulty: Medium
67. (p. 351) In a _____ database, not all the data in a database is physically located in one place.
distributed
Many times the data in a company is stored not in just one location but in several locations. It
is made accessible through a variety of communications networks. The database, then, is a
distributed database.
Difficulty: Easy
68. (p. 352) Dialog Information Services is an example of a _____ database.
commercial
A commercial database is generally an enormous database that an organization develops to
cover particular subjects.
Difficulty: Medium
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Chapter 012 Databases Key
Essay Questions
69. (p. 340) Define the physical and logical views of data.
The physical view of data is concerned with the actual format and physical location of the
data, whereas the logical view concentrates on the meaning and content of the data. Typically,
only very specialized computer professionals are concerned with the physical view of data.
End users and most computer professionals are concerned with the logical view of data. They
are involved with actually using the data with application programs.
Difficulty: Medium
70. (p. 342) Explain the components of data organization.
In the logical view, data is organized into groups or categories. Each group is more complex
than the one before. A character is the most basic logical data element. It is a single letter,
number, or special character, such as a punctuation mark, or a symbol, such as $. The next
higher level is a field or group of related characters. A data field represents an attribute
(description or characteristic) of some entity (person, place, thing, or object). A record is a
collection of related fields. A record represents a collection of attributes that describe an
entity. A table is a collection of related records. A database is an integrated collection of
logically related tables.
Difficulty: Hard
71. (p. 344, 345) What are the advantages of having databases?
For both individuals and organizations, there are many advantages to having databases. These
include:
Sharing: In organizations, information from one department can be readily shared with others.
Security: Users are given passwords or access only to the kind of information they need.
Less data redundancy: Without a common database, individual departments have to create and
maintain their own data and data redundancy results. Redundant data causes inefficient use of
storage space and data maintenance problems.
Data integrity: When there are multiple sources of data, each source may have variations.
Difficulty: Medium
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Chapter 012 Databases Key
72. (p. 345, 346) List and describe the five basic DBMS subsystems.
The DBMS engine provides a bridge between the physical and logical views of the data.
When users request data (logical perspective), the DBMS engine handles the details of
actually locating the data (physical perspective). The data definition subsystem defines the
logical structure of the data by using the data dictionary or schema. The data manipulation
subsystem provides tools for maintenance and analysis of data. Data maintenance includes
adding new data, deleting old data, and editing existing data. Analysis tools support viewing
all or selected parts of the data, querying the database, and generating reports. Specific tools
include query-by-example and specialized programming languages called structured query
languages (SQL). The application generation subsystem provides tools for creating data entry
forms and specialized programming languages that interface with common programming
languages. The data administration subsystem helps to manage the overall database, including
maintaining security, providing disaster recovery support, and monitoring the overall
performance of database operations.
Difficulty: Hard
73. (p. 347) Describe the structure and functionality of a hierarchical database.
In a hierarchical database, fields or records are structured in nodes. Nodes are points
connected like the branches of an upside-down tree. Each entry has one parent node, although
a parent may have several child nodes. This is sometimes described as a one-to-many
relationship. To find a particular field, you have to start at the top with a parent and trace
down the tree to a child.
Difficulty: Medium
74. (p. 348) How does a relational database differ from a hierarchical database?
A relational database is more flexible than a hierarchical database. In a relational database,
there are no access paths down a hierarchy. Instead, data elements are stored in different
tables, each of which consists of rows and columns. All related tables have a common data
item (key field) enabling information stored in one table to be linked with information stored
in another.
Difficulty: Medium
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75. (p. 350) Describe the workings of an object-oriented database.
Object-oriented databases are more flexible and store data as well as instructions to
manipulate the data. Object-oriented databases organize data using classes, objects, attributes,
and methods. Classes are general definitions (for example, Employee). Objects are specific
instances of a class that can contain both data and instructions to manipulate the data (for
example, individual employees). Attributes are the data fields an object possesses (for
example, first name, last name, address, wage). Methods are instructions for retrieving or
manipulating attribute values (for example, a formula to define pay (wage x hours)).
Difficulty: Hard
76. (p. 351) What is the difference between the individual database and the company database?
The individual database, also called a microcomputer database, is a collection of integrated
files primarily used by just one person. Typically, the data and the DBMS are under the direct
control of the user. They are stored either on the user's hard-disk drive or on a LAN file
server. In contrast, the company database may be stored on a central database server and
managed by a database administrator. Users throughout the company have access to the
database through their microcomputers linked to local or wide area networks. Company
databases are the foundation for management information systems.
Difficulty: Medium
77. (p. 352) Explain commercial databases with examples.
A commercial database is generally an enormous database that an organization develops to
cover particular subjects. It offers access to this database to the public or selected outside
individuals for a fee. Sometimes commercial databases are also called information utilities or
data banks. Some important commercial databases include: CSi, Dialog Information Services,
Dow Jones Interactive Publishing, and LexisNexis.
Difficulty: Medium
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78. (p. 353) What are some measures that can be taken to ensure a database's security?
Most databases require some sort of login as the most basic security measure. Security may
require putting guards in company computer rooms and checking the identification of
everyone admitted. Some security systems electronically check fingerprints. Most major
corporations today use specialized hardware and software called firewalls to control access to
their internal networks.
Difficulty: Easy
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