CS 682 Chapter 8
124. Which normal form deals with repeating attributes? A) 1NF B) 2NF C) 3NF D) all of these E) none of these
1NF
128. Which normal form deals with transitive dependencies? A) 1NF B) 2NF C) 3NF D) all of these E) none of these
3NF
121. Which of the following is a criteria for making a good data model? A) A good data model is simple. B) A good data model is essentially nonredundant. C) A good data model should be flexible and adaptable to future needs. D) Each data attribute should describe at most one entity. E) All of these.
All of these.
108. A relationship where many instances of one entity can be associated with many instances of another entity is known as: A) ternary B) many-to-many C) nonspecific D) B and C E) none of these
B and C
145. ________________________________ defines the minimum and maximum number of occurrences of one entity for a single occurrence of the related entity.
Cardinality
170. ______________________________________ is a technique for organizing and documenting a system's data.
Data Modeling
114. Which of the following statements is false?: A) Data models help analysts to quickly identify business vocabulary more completely than process models. B) Data models are almost always built more quickly than process models. C) Data models for existing and proposed systems are far more similar than process models for existing and proposed systems. D) Data modelers frequently get hung up on unnecessary details associated with the data. E) None of these.
Data modelers frequently get hung up on unnecessary details associated with the data.
139. The ________________________________ is the value that will be recorded for an attribute if a user does not specify one.
Default value
146. The ___________________________ of a relationship is the number of entity classes that participate in the relationship.
Degree
172. A(n) _________________________ is something that the business needs to store data.
Entity
11. A compound attribute is an attribute that will be expanded into a separate entity.
False
15. The domain value for an attribute is the value that will be recorded if not specified by the user.
False
17. A key is an attribute or group of attributes that assumes a unique value for each entity instance. It is sometimes called the domain of the attribute.
False
2. Data modeling is a technique for organizing and documenting a system's logical and physical models.
False
20. A candidate key must be a single attribute.
False
27. A subsetting criteria is a domain of attributes whose values are limitless to allow for a variety of subsets to be constructed from a database.
False
29. A relationship may represent an event that links the entities or merely a physical affinity that exists between the entities.
False
30. All data model relationships are unidirectional.
False
32. Conceptually cardinality defines the minimum and maximum attributes that can be added to an entity.
False
34. The domain of a relationship is the number of entities that participate in the relationship.
False
42. A foreign key in the parent entity always matches the primary key in the child entity.
False
44. Nonidentifying relationships are those in which each of the participating entities has dependent primary keys.
False
48. A many-to-many relationship is one in which many entities are associated with other attributes of a different entity.
False
50. Generalization is a technique wherein the domains common to several types of attributes are grouped into their own entity, called an associate entity.
False
52. An entity supertype is an entity whose instances inherit some common attributes from an entity subtype and then add other attributes that are unique to an instance of the supertype.
False
54. An enterprise data model typically identifies and defines only the most complex entities used by the enterprise.
False
58. The requirements analysis results in a physical data model that is developed in stages as follows: (1) normalized data model; (2) key-based data model; (3) fully attributed data model; and (4) the context data model.
False
75. If use-case narratives have been written during the requirements analysis phase, analysts can scan them for verbs to discover data attributes and entities.
False
8. An entity existence is a single occurrence of an entity.
False
80. In a good data mode, each data attribute describes at most one entity.
False
82. A good data model is inflexible because it is an accurate representation of the business data requirements.
False
83. Data analysis is a process that prepares a logical model for implementation as a redundant, explicit, and finite database through a technique called generalization.
False
87. An entity is in third normal form (3NF) if it is already in 2NF and if the values of all nonprimary key attributes are dependent on the full primary key - not just part of it.
False
88. An entity is in first normal form (1NF) if the values of its nonprimary key attributes are not dependent on any other nonprimary key attributes.
False
89. One form of 3NF makes sure that transitive dependencies exist in each entity.
False
91. A data-to-location CRUD matrix is a table in which garbage values that fall outside the domain of an attribute are identified and used for data verification.
False
93. A generalization hierarchy can be at most two levels deep.
False
154. _______________________________ is an approach that seeks to discover and exploit the commonalties between entities.
Generalization
153. ________________________________ relationships are those in which each of the participating entities has its own independent primary key.
Nonidentifying
120. Which of the following is NOT a guideline for creating a business coding scheme? A) Codes should be expandable to accommodate growth. B) The full code must result in redundant values for entities. C) Codes should be large enough to describe distinguishing characteristics, but small enough to be interpreted by a person without a computer. D) Codes should be convenient. E) All of these
The full code must result in redundant values for entities.
1. Data modeling is a technique for defining business requirements for a database.
True
10. A compound attribute is one that actually consists of other attributes that are logically grouped together.
True
12. The data type of an attribute defines what type of data can be stored in that attribute.
True
13. Example data types include: numbers, text, memo, date, time, yes/no, Boolean, value set, or image.
True
14. The domain of an attribute defines what values an attribute can legitimately take on.
True
18. A concatenated key is a group of attributes that uniquely identifies an instance of an entity.
True
19. A concatenated key is also known as a composite key or a compound key.
True
21. A candidate key may be a single attribute or a concatenated key.
True
22. A primary key is that candidate key that will most commonly be used to uniquely identify a single entity instance.
True
23. An example of domain would be an attribute called grade where the values could only be A, B, C, D, E, or F.
True
24. An alternate key is also known as a secondary key.
True
25. A subsetting criteria is an attribute or concatenated attribute whose finite values divide all entity instances into useful subsets.
True
28. A relationship is a natural business association that exists between one or more entities.
True
3. Data modeling is sometimes called database modeling because a data model is eventually implemented as a database.
True
31. Because all relationships are bi-directional in an entity relationship diagram, cardinality must be defined in both directions for every relationship.
True
33. The degree of a relationship is the number of entities that participate in the relationship.
True
35. A recursive relationship is when only one entity participates in the relationship.
True
37. A recursive relationship identifies a relationship that may exist between different instances of the same entity.
True
38. A ternary relationship is a relationship among three entities.
True
39. The relationship between a student entity and a curriculum entity would be classified as recursive.
True
4. An entity is something about which the business needs to store data.
True
40. In a one-to-many relationship, the parent is the entity on the "one" side.
True
41. A foreign key in a child entity always matches the primary key in the parent entity.
True
43. Nonidentifying relationships are those in which each of the participating entities has its own independent primary key. That is, none of the primary key attributes is shared.
True
45. Identifying relationships are those in which the parent entity contributes its primary key to become part of the primary key of the child entity.
True
47. A non-specific relationship is one in which many instances of one entity are associated with many instances of another entity.
True
49. Generalization is a technique wherein the attributes that are common to several types of an entity are grouped into their own entity, called a supertype.
True
5. An entity is a class of persons, places, objects, events or concepts about which we need to capture and store data.
True
51. An entity subtype is an entity whose instances inherit some common attributes from an entity supertype and then add other attributes that are unique to an instance of the subtype.
True
53. An enterprise data model typically identifies only the most fundamental of entities of the enterprise.
True
55. The data model for a single information system is usually called an application data model.
True
57. The requirements analysis results in a logical data model that is developed in stages as follows: (1) context data model; (2) key-based data model; (3) fully attributed data model; and (4) the normalized data model.
True
59. During systems design, the logical data model will be transformed into a physical data model.
True
7. An entity instance is a single occurrence of an entity.
True
70. Serial codes assign sequentially generated numbers to entity instances.
True
71. Alphabetic codes use finite combinations of letters (and possibly numbers) to describe entity instances.
True
72. In significant position codes, each digit or group of digits describes a measurable or identifiable characteristic of the entity instance.
True
73. Significant position codes are frequently used to code inventory items.
True
74. Hierarchical codes provide a top-down interpretation for an entity instance by factoring an item into its group, subgroup and so forth.
True
77. Many organizations have naming standards and approved abbreviations for data attributes.
True
78. A good data model is simple.
True
79. A good data model is essentially nonredundant.
True
81. A good data model should be flexible and adaptable to future needs.
True
84. An entity is in first normal form (1NF) if there are no attributes that can have more than one value for a single instance of the entity.
True
85. An entity is in second normal form (2NF) if it is already in 1NF and if the values of all nonprimary key attributes are dependent on the full primary key - not just part of it.
True
9. An attribute is a descriptive property or characteristic of an entity.
True
90. A data-to-location CRUD matrix is a table in which the rows indicate entities (and possible attributes); the columns indicate locations; and the cells (the intersection of the rows and columns) document level of access where C=create; R=read; U=update; and D=delete or deactivate.
True
92. Many nonspecific relationships can be resolved into two one-to-many relationships using an associative entity.
True
130. A table in which rows indicate entities (and possible attributes) and the columns indicate locations, and the cells indicate the document level of access including create, read, update or delete is known as: A) an entity relationship table B) a transitive dependency table C) a data-to-location CRUD matrix D) a decision table E) none of these
a data-to-location CRUD matrix
119. A code that provides a top-down interpretation for an entity instance is known as: A) a serial code B) a structured code C) a significant position code D) a hierarchical code E) none of these
a hierarchical code
117. A code that assigns sequentially generated numbers to entity instances is known as: A) a serial code B) a sequential code C) an alphabetic code D) a significant position code E) none of these
a serial code
129. When a nonkey attribute is dependent on another nonkey attribute (other than by derivation) is known as: A) an associative dependency B) a concatenation dependency C) a transitive dependency D) a derived dependency E) none of these
a transitive dependency
131. An entity relationship diagram: A) is used in data modeling. B) depicts data in terms of entities and relationships. C) identifies the cardinality of a relationship. D) makes clear the degree of a relationship. E) all of these
all of these
132. An entity: A) is something about which the business needs to store data. B) is a class of persons, places, objects, events or concepts about which we need to capture and store data. C) can have many instances. D) can have many attributes. E) all of these
all of these
94. Which of the following is a category of entities? A) person B) place C) object D) concept E) all of these
all of these
135. Which of the following is NOT a source for entity discovery? A) JRP sessions B) interviews with users C) forms from the existing system D) use-case narratives E) all of these can be used as sources
all of these can be used as sources
101. If an employee entity had both an EmployeeID attribute and a Social Security Number attribute, the one that was not used as the primary key would be called a(n): A) entity key B) concatenated key C) alternate key D) candidate key E) all of these
alternate key
95. A descriptive property or characteristic of an entity is: A) a domain B) an attribute C) an entity instance D) an entity existence E) none of these
an attribute
140. Every entity must have __________________________.
an identifier or a key
151. A(n) ________________________________ entity is an entity that inherits its primary key from more than one other entity (parents). Each part of that concatenated key points to one and only one instance of each of the connecting entities.
associative
105. A ternary relationship is: A) recursive B) reflexive C) between three entities D) is not possible in data modeling E) none of these
between three entities
144. All relationships are implicitly _____________________________.
bi-directional
148. A(n) _____________________________ relationship is the most common type, where two entities participate.
binary
118. A code that uses blocks of numbers that are divided into groups that have some business meaning is known as a: A) serial code B) hierarchical code C) significant position code D) block code E) none of these
block code
123. The process that prepares a data model for implementation as a database is known as: A) contextualization B) normalization C) data analysis D) both normalization and data analysis E) none of these
both normalization and data analysis
103. What defines the minimum and maximum number of occurrences of one entity that may be related to a single occurrence of the other entity? A) domain B) concatenation C) associative entity D) cardinality E) none of these
cardinality
133. Every student resides in 0 or 1 dorm. This is an example of:A) domain A) default B) degree C) cardinality D) nonspecific relationship
cardinality
175. The entity on the "many" side of a one-to-many relationship is called the _____________.
child
141. A group of attributes that uniquely identifies an instance of an entity is called a(n) __________________________________.
concatenated key
113. During requirements analysis, what order of model development is used to arrive at the logical data model? A) context data model; fully attributed data model; key-based data model; normalized data model B) normalized data model; context data model; fully attributed data model; key-based data model C) normalized data model; key-based data model; fully attributed data model; context data model D) context data model; key-based data model; fully attributed data model; normalized data model E) none of these
context data model; key-based data model; fully attributed data model; normalized data model
122. The process that prepares a data model for implementation as a simple, nonredundant, flexible and adaptable database is known as: A) process analysis B) requirements analysis C) data analysis D) generalization E) none of these
data analysis
137. The three properties of an attribute are: ___________________________, _______________________, and _____________________________.
data type, domain and default
171. Data modeling is sometimes called __________________________________ because a data model is usually implemented as a database.
database modeling
98. The value that is recorded in an attribute if a user does not specify one is known as the: A) domain B) key C) default value D) data type E) none of these
default value
125. An attribute whose value can be calculated from other attributes is called a(n): A) compound attribute B) derived attribute C) domain attribute D) false attribute E) none of these
derived attribute
138. The ___________________________ defines what values an attribute can legitimately take.
domain
97. What defines what values an attribute can legitimately take on? A) realm B) entity C) relationship D) domain E) none of these
domain
173. Categories of _______________________ include: persons, places, objects, events or concepts.
entities
152. A(n) _______________________________ key is a primary key of one entity that is contributed to (duplicated in) another entity to identify instances of a relationship.
foreign
109. A technique wherein attributes that are common to several types of an entity are grouped into their own entity called a supertype is called: A) normalization B) generalization C) concatenation D) compound data type E) none of these
generalization
155. _______________________________ is a technique where the attributes are grouped to form entity supertypes and subtypes.
generalization
107. When a parent entity contributes its primary key to become part of the primary key of the child entity, the relationship is known as: A) primary B) associative C) nonidentifying D) identifying E) none of these
identifying
99. An attribute or group of attributes that assumes a unique value for each entity instance is a: A) domain B) key C) default value D) data type E) none of these
key
150. A(n) ________________________________ relationship is where many instances of one entity are associated with many instances of another entity.
many-to-many or non specific relationship.
115. A true entity: A) must have only one instance B) must have many possible instances C) must have a recursive relationship D) must have the same cardinality and degree E) all of these
must have many possible instances
174. Categories of entities include: ____________, _______________, _______________, _______________________, or ______________________.
persons, places, objects, events, or concepts
142. A candidate key is the candidate to become the ___________________________ of instances of an entity.
primary key or identifier
147. A(n) _______________________________ relationship is where a relationship exists between different instances of the same entity.
recursive or unary
143. A(n) _____________________________ is a natural business association that exists between one or more entities.
relationship
158. Another name for an alternate key is ______________________________ key.
secondary
102. An attribute or concatenated attribute whose values divide all entity instances into useful subsets is known as: A) primary criteria B) secondary criteria C) alternate criteria D) subsetting criteria E) none of these
subsetting criteria
159. A _______________________________________ is an attribute (or concatenated attribute) whose finite values divide all entity instances into useful subsets.
subsetting criteria or inversion entry
157. A ___________________________ is an entity whose instances inherit some common attributes from an entity supertype and then add other attributes that are unique to its instance.
subtype
110. An entity whose instances store attributes that are common to one or more entities is a(n): A) supertype B) subtypes C) compound type D) default type E) none of these
supertype
149. A(n) _____________________________ relationship is one between three different entities.
ternary
100. Any candidate key that is not selected to become the primary key is called: A) the entity key B) the concatenated key C) the subsetting key D) the domain key E) the alternate key
the alternate key
111. The data model for a single information system is usually called: A) the enterprise data model B) the logical data model C) the physical data model D) the application data model E) none of these
the application data model
134. In the relationship between cities and residents, the resident entity would be: A) the child B) the parent C) nonspecific D) subtype E) supertype
the child
112. The problem analysis phase model that includes only entities and relationships but no attributes is known as: A) the enterprise data model B) the application data model C) the context data model D) does not exist, all data models must have attributes E) none of these
the context data model
104. The number of entities that can participate in a relationship is known as: A) the domain of the relationship B) the cardinality of the relationship C) the degree of the relationship D) the association of the relationship E) none of these
the degree of the relationship
127. An entity is in third normal form if: A) all the values of primary keys are independent on the nonprimary keys. B) values of nonprimary key attributes are not dependent on any other nonprimary key attributes. C) values of its nonprimary key attributes are dependent on any other nonprimary key attributes. D) you add additional nonkey attributes that are dependent on other nonkey attributes. E) none of these.
values of nonprimary key attributes are not dependent on any other nonprimary key attributes.