Multiple Choice
Identify the
letter of the choice that best completes the statement or answers the question.
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1.
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Database designers must obtain a precise description of the nature of the ________ and
the many uses of such data within an organization.
a. | sources | b. | data | c. | software | d. | objects | | |
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2.
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The
entity relationship (E-R) model is used to ___________ the different views of the data at the
conceptual level.
a. | display | b. | divide | c. | simplify | d. | consolidate | | |
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3.
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The
Chen model is especially useful to illustrate some of the ___________ elements of database
design.
a. | developmental | b. | conceptual | c. | actual | d. | specific | | |
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4.
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The
Crow's Foot model is more ___________-oriented than the Chen model.
a. | object | b. | user | c. | implementation | d. | processor | | |
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5.
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Database designers employ data models as communications tools to facilitate the
interaction among
a. | the designers. | b. | the applications
programmers. | c. | the users. | d. | all of the
above. | | |
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6.
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The
American National Standards Institute/Standards Planning and Requirements Committee defines _____
different data models.
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7.
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ANSI/SPARC defines different data models according to their degree of abstraction
as
a. | conceptual. | b. | external. | c. | internal. | d. | none of the above | e. | all of the
above | | |
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8.
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Successful database design is first and foremost based on _____________
requirements.
a. | designer | b. | programmers | c. | end-user | d. | business | | |
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9.
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The
conceptual model represents a _____________ view of the data.
a. | single | b. | simple | c. | partial | d. | global | | |
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10.
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In a
conceptual model, the DBMS only needs a(n) _____________ for the relationship.
a. | name | b. | object | c. | table | d. | all of the above | e. | none of the
above | | |
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11.
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The
external model yields some advantages such as ______________
a. | use of the
database subsets to make application program development much simpler. | b. | use of the
database subsets to make application program development much harder. | c. | use of the
database subsets to make application program development impossible to
create. | d. | use of the database subsets to make application program
development much cumbersome. | | |
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12.
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The
external model yields some advantages such as ______________
a. | facilitating the
designer's task by making it harder to identify specific data required to support each business
unit's operations. | b. | facilitating the designer's task by making it cumbersome to
identify specific data required to support each business unit's operations. | c. | facilitating the
designer's task by making it more complex to identify specific data required to support each business
unit's operations. | d. | facilitating the designer's task by making it easier to
identify specific data required to support each business unit's operations. | | |
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13.
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The
external model yields some advantages such as ______________
a. | making the
designer's job more complex by not providing feedback about the conceptual model's
adequacy. | b. | making the designer's job cumbersome by providing feedback
about the physical model's adequacy. | c. | making the designer's job easier by providing feedback about
the conceptual model's adequacy. | d. | making the designer's job easier by providing feedback about
the internal model's adequacy. | | |
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14.
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The
external model yields some advantages such as ______________
a. | helping to
ensure security constraints in the database design. | b. | helping to
ensure security constraints in the table design. | c. | helping to
ensure security constraints in the object design. | d. | helping to
ensure security constraints in the relationship design. | | |
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15.
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The
external model is
a. | DBMS independent and hardware
independent. | b. | DBMS dependent and hardware
dependent. | c. | DBMS dependent and hardware
independent. | d. | DBMS independent and hardware
dependent. | | |
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16.
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Attributes are classified as
a. | simple. | b. | composite. | c. | multivalued. | d. | b and
c | e. | a and
b | | |
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17.
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The
conceptual model
a. | can handle M:N relationships. | b. | can handle
multivalued attributes. | c. | should not be implemented in the relational
DBMS. | d. | all of the above | e. | none of the
above | | |
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18.
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A
derived attribute
a. | must be stored physically within the
database. | b. | need not be physically stored within the
database. | c. | is derived by using an algorithm. | d. | a and
c | e. | b and
c | | |
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19.
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A
relationship is an association between
a. | objects. | b. | entities. | c. | databases. | d. | fields. | | |
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20.
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Cardinality expresses __________ number of entity occurrences associated with one
occurrences of the related entity.
a. | an undetermined | b. | the
specific | c. | a pre-determined | d. | a programmed
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21.
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Knowing the ______________ number of entity occurrences is very helpful at the
application software level.
a. | maximum | b. | minimum | c. | exact | d. | maximum and
minimum | | |
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