A record consists of a ____
character
collection of related records
set of one or more field
group of files
A DBMS performs several important functions that guarantee the integrity and consistency of the data in the database. Which of the following is NOT one of those functions?
Data integrity management
Data storage management
Data reports
Security management
Which item is unstructured data
A record representing one student
A video
A table that holds student data
A relational database that hold course registration data
Data is/are
information
raw facts
processed information
DBMS
Which classification is correct for the box marked “Registration” in the given E-R Diagram?
Intersection data
Modality data
Cardinality data
Student data
Which type of relationship exists between Student and Course
One-to-many binary
Many-to-many binary
One-to-many unary
Many-to-many unary
What is the E-R Diagram about an online pet food vendor showing?
An Invoice Line can include many Items
An item can only be included in one Invoice Line
One Invoice Line must include a minimum of one and a maximum of one Item.
The relationship between Item and Invoice Line is many-to-many.
A pet owner can have many pets; a specific pet is linked to one pet owner.
One-to-one
One-to-many
Many-to-many
Associative
Database models were developed to ____
model real-world events or conditions
deposit data within a single file
keep data within multiple data repositories
allow DBMSs to maintain loose control over the database activities
What is the correct way to read the modality on the right side of the association?
A maximum of one activity
A maximum of zero activities
A minimum of zero activities
A maximum of many activities
What is the modality of Volunteer?
Two or more
Two
Dependent on registration date
At least one
What type of relationship is expressed with the phrase “A Painter paints one or more Paintings”?
1:M
1:1
M:1
M:N
The entity integrity rule requires that ____
all primary key entries are unique
a part of the key may be null
foreign key values do not reference primary key values
duplicate object values are allowed
What does the ‘refer’ in referential integrity mean ?
The relationships between entities and attributes, also called referrals
Reference points that databases place in each record during backups
A foreign key in a table must refer to a valid primary key in another table.
You delete a row in one table whose primary key does not have a matching foreign key value in another table
A table is perceived as a ____
flat structure
two-dimensional structure
linked structure
graph
Another word for the term “relation” is _____
datafile
data index
table
data query
DISTINT filters the results to remove duplicates. ORDER BY _____
does the same thing.
alters the order of the rows in a table.
modifies the presentation by changing the order of the result set.
removes duplicates in the table.
A primary key ____.
is a minimal superkey
is always the first field in each table
must be numeric
must be unique
A table can be logically connected to another table by defining a ____
hyperlink
common attribute
primary key
logic key
A relational operator that allows for the combination of information from two or more tables is known as the ____ operator
SELECT
PROJECT
JOIN
DIFFERENCE
Which of the following statements concerning the primary key is true?
All primary key entries are unique.
The primary key may be null.
The primary key is not required for all tables.
The primary key data do not have to be unique.
We can describe a link by observing that ____
a primary key of one table appears again as a primary key in a related table
a foreign key of one table appears again as a foreign key in a related table
a primary key of one table appears again as a foreign key in a related table
a foreign key of one table appears again as a primary key in a related table
When designing a new database, it is a good idea to ____
minimize data redundancy
include redundant fields
include a common field in all tables
use composite keys
An attribute (or combination of attributes) that uniquely identifies each entity in a table is called a ____
superkey
foreign key
master key
secondary key
A foreign key must ____.
be numeric
be unique
be defined in all tables within the database
match the value of a primary key in a related table
The ERD is used to graphically represent the ____ database model.
condensed
physical
logical
conceptual
A derived attribute ____.
must be stored physically within the database
need not be physically stored within the database
has many values
must be based on the value of three or more attributes
A relationship is an association between ____
objects
entities
databases
fields
A ____ key is a key that consists of more than one attribute.
primary
foreign
composite
domain
A ____ attribute is one that cannot be subdivided.
atomic
single-valued
multivalued
If an entity can exist apart from one or more related entities, it is said to be ____-independent
existence
relationship
business
weak
A ____ relationship exists when three entities are associated
unary
binary
ternary
The set of possible values for an attribute is a ____
range
set
key
Which attribute(s) make up the primary key in the table definition:
CLASS (CRS_CODE, CLASS_SECTION, CLASS_TIME, CLASS_ROOM, PROF_NUM)
CRS_CODE
CLASS_SECTION
CRS_CODE and CLASS_SECTION
There is no primary key
A table that has all key attributes defined, has no repeating groups, and all its attributes are dependent on the primary key, is said to be in ____
1NF
2NF
3NF
4NF
A table that is in 2NF and contains no transitive dependencies is said to be in ____
Data redundancy produces ____
slower lookups
robust design
efficient storage use
data integrity problems
Normalization works through a series of normal ____
schemas
forms
Dependencies based on only a part of a composite primary key are called ____ dependencies
partial
incomplete
Given the table EMP_PROJ (PROJ_NUM, EMP_NUM, PROJ_NAME, EMP_NAME, JOB_CLASS, CHG_HOURS, HOURS), which of the following is a partial dependency?
PROJ_NUM --> PROJ_NAME
JOB_CLASS --> CHG_HOUR
PROJ_NUM, EMP_NUM --> HOURS
PROJ_NUM, EMP_NUM --> CHG_HOURS
A relation is not in 1NF if
it has multiple candidate keys
all of the key attributes are defined
there are repeating groups in the table
all attributes are dependent on the primary key
The SQL command that lets you insert data into a table, one row at a time, is ____
INSERT
COMMIT
UPDATE
The SQL command that enables you to make changes in the data is ____
To list all the contents of the PRODUCT table, you would use ____.
LIST * FROM PRODUCT;
SELECT * FROM PRODUCT;
DISPLAY * FROM PRODUCT;
SELECT ALL FROM PRODUCT;
Which command would you use when making corrections to the PRODUCT table?
CHANGE PRODUCT SET P_INDATE = '01/18/2004' WHERE P_CODE = '13-Q2/P2';
ROLLBACK PRODUCT SET P_INDATE = '01/18/2004' WHERE P_CODE = '13-Q2/P2';
EDIT PRODUCT SET P_INDATE = '01/18/2004' WHERE P_CODE = '13-Q2/P2';
UPDATE PRODUCT SET P_INDATE = '01/18/2004' WHERE P_CODE = '13-Q2/P2';
Which command would be used to delete the table row where the P_Code = '2238/QPD'?
DELETE FROM PRODUCT WHERE P_CODE = '2238/QPD';
REMOVE FROM PRODUCT WHERE P_CODE = '2238/QPD'
ERASE FROM PRODUCT WHERE P_CODE = '2238/QPD';
ROLLBACK FROM PRODUCT WHERE P_CODE = '2238/QPD';
Which command is used to select partial table contents?
SELECT <column(s)> FROM <Table name> WHERE <Item>;
LIST <column(s)> FROM <Table name> WHERE <Conditions>;
SELECT <column(s)> FROM <Table name> WHERE <Conditions>;
LIST<column(s)> FROM <Table name> WHERE <Item>;
Which query will output the table contents when the value of V_CODE is less than or equal to 21344?
SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE FROM PRODUCT WHERE V_CODE <> 21344;
SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE FROM PRODUCT WHERE V_CODE <=21344;
SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE FROM PRODUCT WHERE V_CODE => 21344;
SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE FROM PRODUCT WHERE V_CODE = 21344;
Which query will list all the rows in which the inventory stock dates occur on or after January 20, 2006?
SELECT P_DESCRIPT, P_QOH, P_MIN, P_PRICE, P_INDATE FROM PRODUCT WHERE P_INDICATE >= '01/20/2006'
SELECT P_DESCRIPT, P_QOH, P_MIN, P_PRICE, P_INDATE FROM PRODUCT WHERE P_INDICATE >= #01/20/2004#
SELECT P_DESCRIPT, P_QOH, P_MIN, P_PRICE, P_INDATE FROM PRODUCT WHERE P_INDICATE >= '20-JAN-2004'
SELECT P_DESCRIPT, P_QOH, P_MIN, P_PRICE, P_INDATE FROM PRODUCT WHERE P_INDICATE >= {01-20-2004}
What is the SQL syntax requirement to list the table contents for either V_CODE = 21344 or V_CODE = 24288?
SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE FROM PRODUCT WHERE V_CODE = 21344 OR V_CODE <= 24288
SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE FROM PRODUCT WHERE V_CODE = 21344 OR V_CODE => 24288
SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE FROM PRODUCT WHERE V_CODE = 21344 OR V_CODE > 24288
SELECT P_DESCRIPT, P_INDATE, P_PRICE, V_CODE FROM PRODUCT WHERE V_CODE = 21344 OR V_CODE = 24288
What is the command to join the P_DESCRIPT and P_PRICE fields from the PRODUCT table and the V_NAME, V_AREACODE, V_PHONE, and V_CONTACT fields from the VENDOR table where the value of V_CODE match?
SELECT P_DESCRIPT, P_PRICE, V_NAME, V_CONTACT, V_AREACODE, V_PHONE FROM PRODUCT, VENDOR WHERE PRODUCT.V_CODE <> VENDOR.V_CODE;
SELECT P_DESCRIPT, P_PRICE, V_NAME, V_CONTACT, V_AREACODE, V_PHONE FROM PRODUCT, VENDOR WHERE PRODUCT.V_CODE = VENDOR.V_CODE
SELECT P_DESCRIPT, P_PRICE, V_NAME, V_CONTACT, V_AREACODE, V_PHONE FROM PRODUCT, VENDOR WHERE PRODUCT.V_CODE <= VENDOR.V_CODE;
SELECT P_DESCRIPT, P_PRICE, V_NAME, V_CONTACT, V_AREACODE, V_PHONE FROM PRODUCT, VENDOR WHERE PRODUCT.V_CODE => VENDOR.V_CODE;
SQL allows the use of special operators in conjunction with the WHERE clause. A special operator used to check for similar character strings is ____.
BETWEEN
IS NULL
LIKE
IN
A table can be deleted from the database by using the ____ command.
DROP
DELETE
MODIFY
ERASE
UPDATE tablename ***** [WHERE conditionlist]; What command replaces the ***** in the above statement?
SET columnname = expression
columnname = expression
expression = columnname
LET columnname = expression
A ____ join returns rows with matching values and includes all rows from both tables (T1 and T2) with unmatched values.
natural
cross
full outer
left outer
During which step in the extract, transform, load (ETL) process are raw data sets aggregated?
Transformation
Extraction
Loading
Denormalization
Which is an important issue associated with the loading component of extract, transform, load (ETL)?
Mapping keys from one system to another
Monitor refreshing volume and frequency
Determining the content of the data
Denormalizing and renormalizing data
A database includes the table shown above in the exhibit. Each teacher is associated with exactly one campus. The address in the table is the address for the campus where the teacher teaches.
What change would you need to make to normalize the database to the third normal form (3NF)?
Combine the FirstName and LastName columns into a single column.
Combine the Campus, Address, City, State, Country, and PostalCode columns into a single column.
Create a separate table for campus address information. Use the Campus as the primary key. Add a TeacherID column to the table and relate it to the Teacher ID column in the Teachers table.
Create a separate table for campus address information. Use Campus as the primary key for the table. Create a foreign key in the Teachers table that relates teacher to the campus.
Which statement will remove all rows from the Materials table that have a Status value of ‘Obsolete’ but do not have a value for the VendorID column?
DELETE Materials WHERE Status = ‘Obsolete’ OR VendorID IS NULL
DELETE FROM Materials WHERE Status = ‘Obsolete’ AND VendorID IS NULL
DELETE MaterialID, Description, Status, VendorID FROM Materials WHERE Status = ‘Obsolete’ AND VendorID IS NULL
DELETE FROM Materials WHERE Status = ‘Obsolete’ WHERE VendorID IS NULL
The TestScores table is shown in the exhibit and has these characteristics: Each student has a unique StudentID that references the Students table. A specific test can be taken more than once. Each instructor has a unique InstructorID that references the Instructors table Each student may take multiple tests on the same date. Each student may take tests on multiple dates.
What column or columns should you use for the primary key?
StudentID, Date
StudentID, Test, Date, InstructorID
StudentID, Test, and Date
Test
You are creating a relational database to store information about instructors and the courses that each instructor teaches. Each course is taught by a single instructor.
You have created an Instructor table and a Course table as shown above. You need to create a relationship between the Instructor table and the Course table. You need to keep duplicate data to a minimum. What should you do?
Create a new column in the Instructor table.
Create new columns in the Instructors table for each course taught
Create a new table that includes two columns.
Create a new column in the Course table
Which of the following is structured data?
Images
Email Attachments
Records in a database
Audio/Video
Which kind of relationship does the diagram depict?
Unary one-to-many
Binary many-to-many
Unary many-to-many
Binary one-to-many
Unary one-to-one
What is the modality of appointment?
Dependent on the quantity
What form is this table in?
Unnormalized
First normal form
Second normal form
Third normal form
Affinity grouping question – Where does affinity grouping occur in data mining?
Between objects
Among clusters
Among entities and target applications
Between entity group names
How is prediction distinguished from estimation in data mining?
Estimation assumptions do not need to be tested.
Prediction is used to look at historical data only.
Estimation divides small collections of entities into smaller groups of similar entities.
Prediction classifies objects according to an expected future behavior.
Conversion
Which issues is focused on the loading component of extract, transform, load (ETL)?
Denormalizaing and renormalizing the data
How can a data warehouse assist in an organization’s data analysis?
By serving as the primary source of information that feeds analytical processing
By storing data that is no longer in use but may be needed for future analyses
By providing a place where unnormalized data can reside before it is processed
By providing a physical space where groups of servers can process data on a large scale
Which set of results should a company expect from implementing a business intelligence system?
Reduced hardware redundancy and decreased workloads
Riskier capital and asset investments and increased throughput
Increased profitability and reduced hardware redundancy
Increased profitability and increased throughput.
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