Deck 6: Relational Databases and SQL

Question 1

Relationships map and define the way in which data can be extracted from a database.

Answer 1

True

Question 2

A model is a complex representation of a simple entity or phenomenon.

Answer 2

False

Question 3

Representing supervisors and their employees as separate entities in the model can lead to data redundancy.

Answer 3

True

Question 4

A legacy system is one that has existed in an organization for less than one year.

Question 5

The cardinality constraint is used less frequently than the participation constraint.

Question 6

The fundamental requirement for moving toward an event-driven model is the complete integration of data related to an organization's business events.

Question 7

A collection of data representing multiple occurrences of a resource, event, or agent is known as a relation.

Question 8

REA stands for resources, entities and agents.

Question 9

A recursive relationship is created when there is an employee being supervised, and another employee is the supervisor.

Question 10

In an REA diagram, the rectangle is used to represent the composite attribute.

Question 11

The first step in identifying all the relationships that should be included in a model is to identify users' existing and desired information.

Question 12

Attributes are often called fields.

Question 13

A primary attribute is the attribute whose value is unique for every entity that will appear in the database.

Question 14

The cardinality constraint is used to specify both the minimum and maximum participation of one entity in the relationship with the other entity.

Question 15

A recursive relationship occurs between two different instances of an entity.

Question 16

An entity in an accounting system can be classified as a resource, event or agent about which data are collected.

Question 17

The notation of (1,1) is used to specify the relationship type of one-to-many.

Question 18

The notation 1:N is used to specify the relationship type of one-to-many.

Question 19

A set of data that describes a single instance of the entity represented by a relation is known as a tuple.

Question 20

The customer street address is often used as the key attribute in an REA diagram.

Question 21

Business intelligence (BI) has been ranked as one of the top nine "key areas" of current developments in business information technology.

Question 22

The DELETE command is the method used to delete a tuple from a relation.

Question 23

A(n) ____ is an item of data that characterizes an entity or relationship.

A) agent
B) composite attribute
C) attribute
D) instance

Question 24

SQL is a powerful database language that can be used to define database systems, query the database for information, generate reports from the database, and access databases from within programs using embedded commands.

Question 25

Which of the following is the entity or agent?

A) Client
B) client number
C) client name
D) client street address

Question 26

The secondary key is specified to uniquely identity each tuple in the relation.

Question 27

A(n) ____ of an entity is one specific thing of the type defined by the entity.

A) agent
B) composite attribute
C) attribute
D) instance

Question 28

Spreadsheets that are kept offline to an organization's enterprise systems can improve internal control.

Question 29

A relation in an ER model is the same as an entity in the REA model.

Question 30

Which of the following is the key attribute?

A) Client
B) client number
C) client name
D) client street address

Question 31

The DELETE command is used when we want to change one or more attribute values.

Question 32

An entity can be classified as all of the following except:

A) resource
B) event
C) tuple
D) agent

Question 33

Queries of a database are driven by SELECT commands.

Question 34

The INSERT command is used to add a single tuple to an existing relation.

Question 35

The UPDATE command demonstrates one of the weaknesses in most forms of SQL.

Question 36

A missing value is called a non-null.

Question 37

Most DBMS available today that include SQL also include mechanisms within the DBMS itself for establishing and enforcing referential integrity.

Question 38

Relational integrity specifies that for every attribute value in one relation that has been specified to allow reference to another relation, the tuple being referenced must remain intact.

Question 39

Knowledge management uses state-of-the art information technologies for storing and analyzing data to help managers make the best possible decisions for their companies.

Question 40

Composite attributes consist of multiple subattributes.

Question 41

The cardinality constraint:

A) specifies the degree of minimum participation of one entity in the relationship with the other entity.
B) provides more information than the participation constraint.
C) is the most common constraint specified in E-R diagrams.
D) all of the above.

Question 42

Which of the following is not a relationship type?

A) one-to-many
B) one-to-one
C) one-to-few
D) many-to-many

Question 43

Customers of Hanson Company, a home furnishings wholesaler, place orders by contacting a sales representative via a toll-free number. Which is the appropriate relationship type for this relationship?

A) 1:1
B) 1:N
C) N:M
D) N:1

Question 44

The mapping of the relationships between entities would be used in the development of a(n):

A) context diagram
B) logical DFD
C) physical DFD
D) REA Model

Question 45

Common aspects of business intelligence include:

A) access to massive amounts of data
B) use spreadsheets
C) does not require an extensive overhaul of the information system
D) all of the above

Question 46

A key attribute is the attribute whose value is:

A) undeterminable
B) unique
C) large
D) the same for all attributes

Question 47

____ specifies that for every attribute value in one relation that has been specified in order to allow reference to another relation, the tuple being referenced must remain intact.

A) Cardinality constraint
B) Participation constraint
C) Referential integrity
D) Economic constraint

Question 48

____ are defined as a set of data that describes an instance of the entity represented by a relation.

A) Attributes
B) Tuples
C) Primary keys
D) Candidate keys

Question 49

A set of data that describes a single instance of the entity represented by a relation is known as a(n) ____.

A) tuple
B) resource
C) agent
D) event

Question 50

For the following entity and attribute model, what would be the key attribute of the Students entity?

A) social security number
B) name
C) address
D) street

Question 51

Which relationship type does (1:N) mean?

A) one-to-many
B) one-to-one
C) one-to-few
D) many-to-many

Question 52

Students at Macom University use a Web-based course registration system. Identify the participation constraint of the following data model relationship. The university maintains student records until they graduate or do not enroll in a course for a 3-year period.

A) N:M
B) 1:N
C) (1,1):(0,N)
D) (1,1):(1,N)

Question 53

Legacy systems do not usually have which of the following characteristics?

A) developed on previous hardware (and/or software) platforms
B) are easily adaptable to enterprise systems
C) have been used by an organization for a long period of time
D) all of the above are typical characteristics of legacy systems

Question 54

Which of the following is a composite attribute?

A) Client
B) client number
C) client name
D) client street address

Question 55

In a relational database, a relation is defined as a collection of data representing multiple occurrences of the following except:

A) a resource
B) an event
C) an activity
D) an agent

Question 56

The sequence of steps in identifying relationships in a model is:

A) evaluate entities as pairs, identify user existing and desired information, evaluate each entity to determine if there is any need for two occurrences of the same entity type to be linked
B) identify user's existing and desired information, evaluate entities as pairs, evaluate each entity to determine if there is any need for two occurrences of the same entity type to be linked
C) evaluate entities as pairs, evaluate each entity to determine if there is any need for two occurrences of the same entity type to be linked, identify user existing and desired information
D) evaluate each entity to determine if there is any need for two occurrences of the same entity type to be linked, evaluate entities as pairs, identify user existing and desired information

Question 57

Which of the following is an attribute but least likely to be the key attribute?

A) Client
B) client number
C) client name
D) client street address

Question 58

Which of the following statements about the participation constraint is false?

A) It specifies the degree of minimum participation of one entity in the relationship with the other entity.
B) The constraint is either 1 or 0.
C) It is the most common constraint in E-R diagrams.
D) It provides more information than the cardinality constraint.

Question 59

SQL

A) has become the de facto standard database language
B) can be used to define database systems
C) both a. and b.
D) none of the above

Question 60

The constraint that is specifies the degree of minimum participation of one entity in the relationship with the other entity is called:

A) cardinality constraint
B) participation constraint
C) economic constraint
D) logical constraint

Question 61

Which is not an SQL command in which data can be changed in the database?

A) INSERT
B) DELETE
C) UPDATE
D) CREATE

Question 62

Exhibit 6-1
The following table is a view of BILLING_HOURS from the various data elements in High-Tech Corp.'s relational database. $\begin{array}{|c|c|c|c|c|c|}\hline\text { I BILLING HOURS }& \text { Employee No } & \text { Clieat No } & \text { Date } & \text { Hours } & \text { Ballizug Rate } \\\hline &\text { B122 } & \text { F26768 } & 20010823 & 8 & 150 \\\hline &\text { A632 } & \text { F11555 } & 20010823 & 7 & 100 \\\hline& \text { B122 } & \text { F26768 } & 20010824 & 8 & 150 \\\hline& \text { A632 } & \text { F11555 } & 20010824 & 6 & 100 \\\hline& \text { B122 } & \text { F26768 } & 20010825 & 9 & 150 \\\hline &\text { A632 } & \text { F11555 } & 20010825 & 10 & 100 \\\hline\end{array}$



-Refer to Exhibit 6-1. Which of the following SQL statements would extract the employee number and date for every instance that had a billing rate of $150?

A) SELECT Employee_No, Date
FROM BILLING_HOURS
WHERE Rate=150
B) QUERY Employee_No, Date
FROM BILLING_HOURS
WHERE Rate=150
C) SELECT Employee_No, Date
WHERE Rate=150
D) QUERY BILLING_HOURS
SELECT Employee_No, Date
WHERE Hours>8

Question 63

A situation in which a particular supplier provides more than one type of inventory item to a firm and a particular type of inventory item is acquired from more than a single supplier is called a(n):

A) one-to-one relationship
B) one-to-many relationship
C) many-to-many relationship
D) entity relationship

Question 64

The following E-R diagram shows a M:N relationship between two relations. To map this E-R diagram into a logical database model:

A) divide the content of the Course relation to establish two relations having 1:N relationships
B) add the primary key of the Student relation as an attribute in the Course relation
C) create a new relation whose primary key is a composite of the primary keys of two relations
D) add the primary key of the Course relation as an attribute in the Student relation

Question 65

______________________________ map and define the way in which data can be extracted from a database.

Question 66

Which of the following commands allow us to join data across multiple tables to link specific pieces of information that are of interest?

A) Select
B) Project
C) Join
D) Display

Question 67

A(n) ______________________________ attribute is the attribute whose value is unique for every entity that will ever appear in the database.

Question 68

Exhibit 6-1
The following table is a view of BILLING_HOURS from the various data elements in High-Tech Corp.'s relational database. $\begin{array}{|c|c|c|c|c|c|}\hline\text { I BILLING HOURS }& \text { Employee No } & \text { Clieat No } & \text { Date } & \text { Hours } & \text { Ballizug Rate } \\\hline &\text { B122 } & \text { F26768 } & 20010823 & 8 & 150 \\\hline &\text { A632 } & \text { F11555 } & 20010823 & 7 & 100 \\\hline& \text { B122 } & \text { F26768 } & 20010824 & 8 & 150 \\\hline& \text { A632 } & \text { F11555 } & 20010824 & 6 & 100 \\\hline& \text { B122 } & \text { F26768 } & 20010825 & 9 & 150 \\\hline &\text { A632 } & \text { F11555 } & 20010825 & 10 & 100 \\\hline\end{array}$



-Refer to Exhibit 6-1. Which of the following SQL statements would extract the client number and date for every instance that an employee worked less than 8 hours any particular day?

A) QUERY BILLING_HOURS
SELECT Client_No, Date
WHERE Hours<8
B) QUERY Client_No, Date
FROM BILLING_HOURS
WHERE Hours>8
C) SELECT Client_No, Date
WHERE Hours<8
D) SELECT Client_No, Date
FROM BILLING_HOURS
WHERE Hours<8

Question 69

Which of following is not a step in the process for specifying relations based on REA diagrams?

A) Determine the attributes for each of the entities.
B) Determine the number of tables.
C) Create a separate relational table for each entity.
D) Implement the relationships among the entities.

Question 70

Exhibit 6-1
The following table is a view of BILLING_HOURS from the various data elements in High-Tech Corp.'s relational database. $\begin{array}{|c|c|c|c|c|c|}\hline\text { I BILLING HOURS }& \text { Employee No } & \text { Clieat No } & \text { Date } & \text { Hours } & \text { Ballizug Rate } \\\hline &\text { B122 } & \text { F26768 } & 20010823 & 8 & 150 \\\hline &\text { A632 } & \text { F11555 } & 20010823 & 7 & 100 \\\hline& \text { B122 } & \text { F26768 } & 20010824 & 8 & 150 \\\hline& \text { A632 } & \text { F11555 } & 20010824 & 6 & 100 \\\hline& \text { B122 } & \text { F26768 } & 20010825 & 9 & 150 \\\hline &\text { A632 } & \text { F11555 } & 20010825 & 10 & 100 \\\hline\end{array}$



-Refer to Exhibit 6-1. Which of the following SQL statements would extract the employee number and date for every instance that an employee worked more than 8 hours any particular day?

A) SELECT Employee_No, Date
FROM BILLING_HOURS
WHERE Hours>8
B) QUERY Employee_No, Date
FROM BILLING_HOURS
WHERE Hours>8
C) SELECT Employee_No, Date
WHERE Hours>8
D) QUERY BILLING_HOURS
SELECT Employee_No, Date
WHERE Hours>8

Question 71

Which is not a step in creating a relation using SQL?

A) assign the relation a name
B) assign each attribute a name
C) specify the constraints on the attributes
D) specify the attributes of the constraints

Question 72

Which of the following is a valid SQL command?

A) MODIFY
B) INSERT
C) ADD
D) APPEND

Question 73

In a relational database, the entity is represented as a(n):

A) Table
B) Network
C) Field
D) Attribute

Question 74

Attributes that consist of multiple subattributes are referred to as ______________________________.

Question 75

Which of the following is not a proper SQL command for creating database relations?

A) Create table employee
B) Create table training_completed
C) Create client
D) Alter table release_time

Question 76

A simplified representation of a complex entity is a(n):

A) instance
B) attribute
C) model
D) relationship

Question 77

A(n) ______________________________ in an accounting system can be classified as a resource, event, or agent about which data is collected.

Question 78

A(n) ______________________________ is an item of data that characterizes an entity or relationship.

Question 79

The SELECT statement has all but one of the following parts:

A) a list of attributes that we wish to SELECT from the database
B) a WHEN clause
C) a list of tables where these attributes can be found
D) a WHERE clause

Question 80

Exhibit 6-1
The following table is a view of BILLING_HOURS from the various data elements in High-Tech Corp.'s relational database. $\begin{array}{|c|c|c|c|c|c|}\hline\text { I BILLING HOURS }& \text { Employee No } & \text { Clieat No } & \text { Date } & \text { Hours } & \text { Ballizug Rate } \\\hline &\text { B122 } & \text { F26768 } & 20010823 & 8 & 150 \\\hline &\text { A632 } & \text { F11555 } & 20010823 & 7 & 100 \\\hline& \text { B122 } & \text { F26768 } & 20010824 & 8 & 150 \\\hline& \text { A632 } & \text { F11555 } & 20010824 & 6 & 100 \\\hline& \text { B122 } & \text { F26768 } & 20010825 & 9 & 150 \\\hline &\text { A632 } & \text { F11555 } & 20010825 & 10 & 100 \\\hline\end{array}$



-Refer to Exhibit 6-1. Which of the following SQL statements would extract the client number and date for every instance that had a billing rate of $150?

A) QUERY BILLING_HOURS
SELECT Client_No, Date
WHERE Rate=150
B) QUERY Client_No, Date
FROM BILLING_HOURS
WHERE Rate=150
C) SELECT Client_No, Date
WHERE Rate=150
D) SELECT Client_No, Date
FROM BILLING_HOURS
WHERE Rate=150