CHAPTER 2: DATA MODELS
1. A data model is usually graphical.
a. True
b. False
2. An implementation-ready data model needn’t necessarily contain enforceable rules to guarantee the integrity of
the data.
a. True
b. False
3. An implementation-ready data model should contain a description of the data structure that will store the end–
user data.
a. True
b. False
4. Within the database environment, a data model represents data structures with the purpose of supporting a
specific problem domain.
a. True
b. False
5. Even when a good database blueprint is available, an applications programmer’s view of the data should match
that of the manager and the end user.
a. True
b. False
stored.
a. True
b. False
7. Database designers determine the data and information that yield the required understanding of the entire
business.
a. True
b. False
Chapter 2: Data Models
8. Business rules apply to businesses and government groups, but not to other types of organizations such as
religious groups or research laboratories.
a. True
b. False
9. Business rules must be rendered in writing.
a. True
b. False
10. In an SQL-based relational database, each table is dependent on every other table.
a. True
b. False
11. In an SQL-based relational database, rows in different tables are related based on common values in common
attributes.
a. True
b. False
12. A disadvantage of the relational database management system (RDBMS) is its inability to hide the
complexities of the relational model from the user.
a. True
b. False
13. Each row in the relational table is known as an entity instance or entity occurrence in the ER model.
a. True
b. False
14. In Chen notation, entities and relationships have to be oriented horizontally; not vertically.
a. True
b. False
15. M:N relationships are not appropriate in a relational model.
a. True
b. False
Chapter 2: Data Models
16. Today, most relational database products can be classified as object/relational.
a. True
b. False
17. The network model has structural level dependence.
a. True
b. False
18. The external model is the representation of the database as “seen” by the DBMS.
a. True
b. False
19. The hierarchical model is software-independent.
a. True
b. False
20. The relational model is hardware-dependent and software-independent.
a. True
b. False
21. A(n) ’s main function is to help one understand the complexities of the realworld environment.
a. node b. entity
c. model d. database
22. A(n) represents a particular type of object in the real world.
a. attribute b. entity
c. relationship d. node
23. A(n) is anything about which data are to be collected and stored.
a. attribute b. entity
c. relationship d. constraint
Chapter 2: Data Models
24. A(n) is the equivalent of a field in a file system.
a. attribute b. entity
c. relationship d. constraint
25. A(n) is bidirectional.
a. attribute b. entity
c. relationship d. constraint
26. A(n) is a restriction placed on the data.
a. attribute b. entity
c. relationship d. constraint
27. are important because they help to ensure data integrity.
a. Attributes b. Entities
c. Relationships d. Constraints
28. are normally expressed in the form of rules.
a. Attributes b. Entities
c. Relationships d. Constraints
29. Students and classes have a relationship.
a. one-to-one b. one-to-many
c. many-to-one d. many-to–many
30. From a database point of view, the collection of data becomes meaningful only when it reflects properly
defined_____.
a. business rules
b. business norms
c. business goals
d. business plans
Chapter 2: Data Models
31. Which of the following is true of business rules?
a. They allow the designer to set company policies with regard to data.
b. They allow the designer to develop business processes.
c. They can serve as a communication tool between the users and designers.
d. They provide a framework for the company’s self-actualization.
32. A noun in a business rule translates to a(n) in the data model.
a. entity b. attribute
c. relationship d. constraint
33. A verb associating two nouns in a business rule translates to a(n) in the data model.
a. entity b. attribute
c. relationship d. constraint
34. The hierarchical data model was developed in the .
a. 1960s b. 1970s
c. 1980s d. 1990s
35. The object-oriented data model was developed in the .
a. 1960s b. 1970s
c. 1980s d. 1990s
36. VMS/VSAM is an example of the .
a. hierarchical model b. file system data model
c. relational data model d. XML data model
37. Oracle 11g is an example of the .
a. hierarchical model b. file system data model
c. relational data model d. XML/Hybrid data model
38. MySQL is an example of the .
a. hierarchical model b. file system data model
c. relational data model d. XML data model
Chapter 2: Data Models
39. In the model, the basic logical structure is represented as an upside-down tree.
a. hierarchical b. network
c. relational d. entity relationship
40. In the model, each parent can have many children, but each child has only one parent.
a. hierarchical b. network
c. relational d. entity relationship
41. The relational data model was developed in the .
a. 1960s b. 1970s
c. 1980s d. 1990s
42. In the model, the user perceives the database as a collection of records in 1:M relationships, where each
record can have more than one parent.
a. hierarchical b. network
43. The model was developed to allow designers to use a graphical tool to examine structures rather than
describing them with text.
a. hierarchical b. network
c. object-oriented d. entity relationship
44. A(n) enables a database administrator to describe schema components.
a. extensible markup language (XML) b. data definition language (DDL)
c. unified modeling language (UML) d. query language
45. Which of the following types of HDFS nodes stores all the metadata about a file system?
a. Data node b. Client node
c. Name node d. Map node
46. Which of the following types of HDFS nodes acts as the interface between the user application and the HDFS?
a. Data node b. Client node
c. Name node d. Map node
Chapter 2: Data Models
47. Which of the following is a disadvantage of the hierarchical data model?
a. It does not promote data sharing. b. It is not efficient with 1:M relationships.
c. It does not promote data integrity. d. It does not have standards.
48. NoSQL databases:
a. are geared toward transaction consistency; not performance. b. support only small amounts of sparse
data.
c. are based on the relational model. d. provide fault tolerance.
49. The model uses the term connectivity to label the relationship types.
a. relational b. network
c. object-oriented d. entity relationship
50. Which of the following is true of NoSQL databases?
a. They do not support distributed database architectures. b. They are not based on the relational
model.
c. They are geared toward transaction consistency rather d. They do not support very large amounts of
than performance. sparse data.
51. The data model is said to be a semantic data model.
a. relational b. network
c. object-oriented d. entity relationship
52. The data model uses the concept of inheritance.
a. relational b. network
c. object-oriented d. entity relationship
53. One of the limitations of the model is that there is a lack of standards.
a. hierarchical b. network
c. relational d. entity relationship
54. The model is the end users’ view of the data environment.
a. abstract b. external
c. conceptual d. internal
Chapter 2: Data Models
55. An internal refers to a specific representation of an internal model, using the database constructs
supported by the chosen database.
a. tuple b. schema
c. object d. value
56. A(n) is a relatively simple representation of more complex real-world data structures.
57. A(n) is a brief, precise, and unambiguous description of a policy, procedure, or principle within a
specific organization.
58. A(n) in a hierarchical model is the equivalent of a record in a file system.
59. A(n) is the conceptual organization of an entire database as viewed by a database administrator.
60. The relational model’s foundation is a mathematical concept known as a .
61. Each row in a relation is called a(n) .
62. Each column in a relation represents a(n) .
63. A(n) defines the environment in which data can be managed and is used to work with the data in the
database.
64. Each row in the relational table is known as a(n) .
65. In , a threepronged symbol represents the “many” side of the relationship.
66. A(n) is a collection of similar objects with a shared structure and behavior.
67. In object-oriented terms, a(n) defines an object’s behavior.
Chapter 2: Data Models
68. is a language based on OO concepts that describes a set of diagrams and symbols used to graphically
model a system.
69. The term is used to refer to the task of creating a conceptual data model that could be implemented in
any DBMS.
70. The is the representation of a database as “seen” by the DBMS.
71. What components should an implementation-ready data model contain?
72. What do business rules require to be effective?
73. What are the sources of business rules, and what is the database designer’s role with regard to business rules?
Chapter 2: Data Models
74. Describe the three parts involved in any SQL-based relational database application.
75. Describe the conceptual model and its advantages. What is the most widely used conceptual model?