Deck 22: Relational Databases

Question 1

A ____________ is a set of rows and columns that provides a "window" through which you can see some of the database data.

A) table
B) view
C) window
D) subquery

Answer 1

B

Question 2

Based on the table below, which of the following statements will return the number of customers in Michigan (MI)?
Customer table

A) SELECT COUNT(*) FROM Customer WHERE State = 'MI' b) SELECT AVG(*) FROM Customer WHERE State = 'MI'
C) SELECT MAX(*) FROM Customer WHERE State = 'MI'
D) SELECT SUM(*) FROM Customer WHERE State = 'MI'

Answer 2

A

Question 3

Which of the following statements is correct?

A) SQL uses double quotes (") to delimit strings. b) The SQL command INSERT AT adds data to a database
C) SQL is not case sensitive.
D) SQL is a part of the Java API.

Answer 3

C

Question 4

Based on the table below, the query that finds all customers who do not live in Pleasantville is _________________.
Customer table

A) SELECT * FROM Customer WHERE City NOT 'Pleasantville'
B) SELECT * FROM Customer WHERE NOT (City = 'Pleasantville')
C) SELECT * FROM Customer WHERE City <> 'Pleasantville'
D) SELECT * FROM Customer WHERE City != 'Pleasantville'

Question 5

Which of the following would be a good primary key for a Course table designed to hold course information for a university?

A) CourseName
B) CourseID
C) CourseCredit
D) CoursePrerequisites

Question 6

In the table below, the ____ correspond(s) to the attributes of a customer in the database.
Customer table

A) foreign key
B) primary key
C) column headers
D) data type

Question 7

Based on the following table, the query that gets the names and complete mailing addresses of all customers is ____________________.
Customer table

A) SELECT * FROM Customer
B) SELECT Name, Address, City, State, Zip INTO Customer
C) SELECT FROM Customer FIELDS Name, Address, City, State, Zip
D) SELECT Name, Address, City, State, Zip FROM Customer

Question 8

Based on the table below, the query that finds the names and zip codes of all customers is _____________________.
Customer table

A) SELECT ALL Name, Zip FROM Customer
B) SELECT Name, Zip
C) SELECT * FROM Customer
D) SELECT Name, Zip FROM Customer

Question 9

A ____________ is a reference to a primary key in a linked table.

A) foreign key
B) primary key
C) column headers
D) data type

Question 10

In database terminology, a column (or combination of columns) that uniquely identifies a row in a table is called a(n) ____.

A) data type
B) attribute
C) primary key
D) column header

Question 11

Which of the following table attributes could be a unique identifier for a person?

A) Name b) SocialSecurityNumber
C) State
D) Birthday

Question 12

Based on the customer table below, which of the attributes do you think represents the primary key?
Customer table

A) Address b) Name
C) Customer_Number
D) Zip

Question 13

A _____________ is a column (or set of columns) whose value uniquely specifies a table record.

A) foreign key
B) primary key
C) column headers
D) data type

Question 14

Complete the following statement, which inserts rows into the following Course table.
____________________ VALUES ('CS221', 'Data Structures', '4', 'J. Jones')
Course table

A) INSERT INTO Course table
B) INSERT FROM Course
C) INSERT INTO Course
D) INSERT INTO Table Course

Question 15

In SQL, the _____________ command is used to issue queries.

A) QUERY
B) UPDATE
C) START
D) SELECT

Question 16

Insert the statement that would remove the following table from the database.
CREATE TABLE Course
(
Course_ID VARCHAR(11),
Credits VARCHAR(4),
Room_No INT(4)
)
____________________

A) DELETE TABLE Course
B) TRUNCATE TABLE Course
C) DROP Course
D) DROP TABLE Course

Question 17

In SQL, the _____________ command is used to issue queries that do not modify the database.

A) APPEND
B) UPDATE
C) MODIFY
D) SELECT

Question 18

In SQL, ____ is used to test for equality.

A) EQUAL b) ==
C) =
D) EQUALS

Question 19

Based on the table below, insert the statement that queries the database for the names of customers who live in the city of Pleasantville: ______________________
Customer table

A) SELECT Name FROM Customer WHERE City 'Pleasantville'
B) SELECT Name FROM Customer WHERE City == 'Pleasantville'
C) SELECT Name FROM Customer WHERE City >< 'Pleasantville'
D) SELECT Name FROM Customer WHERE City = 'Pleasantville'

Question 20

The outcome of a SQL query is a ____________________.

A) table
B) view of the data
C) list
D) subquery

Question 21

All database URLs have the format:

A) jdbc:subprotocol:driver-specific data
B) jdbc/subprotocol/driver/data
C) oracle.jdbc.driver.OracleDriver
D) c:\jdk1.7.0\db\lib\driver.jar

Question 22

In a Java program, the result of a SQL query is returned in a(n) _____________ object.

A) ResultSet
B) connection
C) view
D) driver

Question 23

The acronym JDBC stands for ________:

A) Joint Data Base Center
B) Java Database Control
C) Joint Database Connectivity
D) Java Database Connectivity

Question 24

The ___ symbol in the query string denotes variables that you fill in when you make an actual query

A) ?
B) *
C) !
D) ::

Question 25

What should the database.properties file contain so you can connect to a database?

A) a database URL, user name, password
B) a database URL, the program name, and a JDBC driver
C) a database URL, the program name, and database name
D) the JDBC driver path

Question 26

What statement will return the value of a given key from the configuration file? Assume props is of type Properties.

A) String driver = props.getProperty("database.properties");
B) Connection conn = SimpleDataSource.getProperty("database.properties");
C) String driver = props.getProperty("jdbc.driver");
D) Properties props = SampleDataSource.init("jdbc.driver");

Question 27

A ______________ object can create statement objects that are used to execute SQL commands.

A) ResultSet
B) Connection
C) JDBC
D) Driver

Question 28

If your statement has variable parts, you should use a _________ object.

A) ResultSet
B) ResultSetMetaData
C) PreparedStatement
D) Statement

Question 29

The outcome of a SELECT query is a _________ that you can view and analyze.

A) table
B) list
C) result set
D) subquery

Question 30

What is one reason why you need a finally clause after a try/catch sequence that accesses a database?

A) To commit the changes
B) To display the ResultSet
C) To display the metadata
D) To close the connection

Question 31

Which Java statement connects to a database using a Connection object?

A) Connection conn = new Connection(url, username, password);
B) Conenction conn = DriverManager.getConnection();
C) Connection conn = DriverManager.connect(url, username, password);
D) Connection conn = DriverManager.getConnection(url, username, password);

Question 32

Based on the table below, the SQL statement that changes the address and city of customer 3175, Gregory Adams, to 1337 Parkway Ave and Pembrook, SD, 57462, respectively, is _____________________.
Customer table

A) UPDATE Customer Address = '1337 Parkway Ave', City = 'Pembrook', State = 'SD', Zip = '57462' WHERE FirstName = 'Gregory' AND LastName = 'Adams'
B) UPDATE Customer SET Address = '1337 Parkway Ave', City = 'Pembrook', State = 'SD', Zip = '57462' WHERE FirstName = 'Gregory' AND LastName = 'Adams'
C) UPDATE Customer SET Address = '1337 Parkway Ave', City = 'Pembrook', State = 'SD', Zip = '57462' WHERE Name = 'Gregory Adams'
D) UPDATE Customer SET Address = '1337 Parkway Ave', City = 'Pembrook', State = 'SD', Zip = '57462'

Question 33

The following command will compile a Java program called TestDB:

A) java TestDB.class
B) java TestDB.java
C) javac TestDB.java
D) javac TestDB.class

Question 34

If you encounter an error during updating a transaction, then call the ______ method:

A) undo
B) takeback
C) rollaround
D) rollback

Question 35

Given the following two statements, what does the call to the next() method return?
ResultSet result = statement.executeQuery();
Result.next();

A) The next record in the result.
B) true or false.
C) The primary key.
D) The next column in the table.

Question 36

An example of a lightweight database is:

A) Oracle
B) MS Access
C) Apache Derby
D) MySQL

Question 37

Based on the table below, the SQL statement that changes the last name of customer 3175 to Michael is _____________________.
Customer table

A) UPDATE Customer SET LastName = 'Michael' WHERE Customer_Number = 3175
B) UPDATE Customer SET Customer_Number = 3175 WHERE LastName = 'Michael'
C) UPDATE Customer table SET LastName = 'Michael' WHERE Customer_Number = 3175
D) UPDATE Customer SET FirstName = 'Susan' WHERE LastName = 'Michael'

Question 38

When you execute a rollback:

A) the temporary data are made permanent.
B) the temporary tables are simply discarded.
C) the database stores the changes in a temporary table.
D) it will commit all the updates.

Question 39

What should be on the class path when you launch a Java program that accesses a database?

A) the JDBC driver
B) the derby.jar file
C) the user name and password
D) the JDK

Question 40

Which SQL command(s) modify the data in a database?
I SELECT
II INSERT
III DELETE
IV UPDATE

A) I, II, III
B) II, III
C) II, III, IV
D) III, IV

Question 41

Microsoft Access is an example of a:

A) Heavyweight Java database.
B) Lightweight Java database.
C) Desktop database.
D) Production-quality database.

Question 42

What will the following command do?
Java -classpath derby.sql;. ExecSQL database.properties Product.sql

A) It will execute the statements in the database.properties file.
B) It will execute the statements in the derby.sql file.
C) It will execute the statements in the Product.sql file.
D) It will act as an interactive testing tool only.

Question 43

An example of a production-quality database is:

A) Oracle
B) MS Access
C) Apache Derby
D) Powerbuilder

Question 44

What does the execute method return?

A) ResultSet
B) Query
C) RecordSet
D) boolean

Question 45

Apache Derby is an example of a:

A) Heavyweight Java database.
B) Lightweight Java database.
C) Desktop database.
D) Production-quality database.

Question 46

If your program needs to look at several result sets at the same time, _____.

A) you need to create multiple Statement objects.
B) you can reuse the Statement or PreparedStatement objects
C) you should close the ResultSet before creating a new one.
D) you are not able to see several sets at the same time.

Question 47

When you close a connection:

A) it closes the connection only.
B) it closes the connection and the associated result set.
C) it closes the connection and the associated statement.
D) it closes the connection and closes all statements and result sets.

Question 48

What is the effect of the following statement?
String product_code = result.getString(1);

A) it will return the data in the second column.
B) it will return the data in the first column.
C) it will store the integer 1 as a string in the product_code.
D) it will return the name of the column.

Question 49

An example of a desktop database is:

A) Oracle
B) MS Access
C) Apache Derby
D) MySQL

Question 50

One of the steps for testing the JDBC driver is:

A) to setup your user account.
B) to find the name of the database URL that your driver expects.
C) to install the JDBC driver program.
D) to change the directory to the JDBC driver directory.

Question 51

What is wrong with the following statement?
ResultSet result = statement.execute("SELECT * from emp WHERE empNum = '5'");

A) ResultSet should be String
B) execute should be executeQuery
C) execute should be prepareStatement
D) 5 should not be used as an empNum value

Question 52

If you want to find out about properties of a result set from an unknown table, you need to use:

A) the ResultSet class.
B) the Statement class.
C) the ResultSetData class.
D) the ResultSetMetaData class.

Question 53

What will the following command do?
Java -classpath derby.sql;. ExecSQL database.properties

A) It will execute the statements in the database.properties file.
B) It will execute the statements in the derby.sql file.
C) It will compile the statements in the derby.sql file.
D) It will use ExecSQL program as an interactive testing tool.

Question 54

You can use the generic ____ method to execute arbitrary SQL statements.

A) setString()
B) prepareStatement()
C) executeQuery()
D) execute()

Question 55

When you are done with a Statement object, _______.

A) you should close it and you must close the associated result set as well.
B) you should not close it and should not close the associated result set.
C) you should close it and that automatically closes the associated result set.
D) you should only close the associated result set.

Question 56

What is wrong with the following statement?
Boolean result = statement.execute("SELECT * from emp WHERE empNum = '?'");

A) boolean should be ResultSet
B) execute should be executeQuery
C) execute should be prepareStatement
D) ? should be an integer

Question 57

The ______ class has a next method to visit the next row of a query result.

A) Scanner
B) Statement
C) ResultSet
D) Connection

Question 58

When you first get a result set from the executeQuery method, you need to call ____ to move to the first row

A) first()
B) start()
C) move()
D) next()

Question 59

Oracle is an example of a:

A) Heavyweight Java database.
B) Lightweight Java database.
C) Desktop database.
D) Production-quality database.

Question 60

A ______ lets you fetch a query result, one row at a time.

A) Query
B) Statement
C) ResultSet
D) PreparedStatement

Question 61

In jdbc.URL, the acronym URL stands for:

A) Universal Resource Locator
B) Uniform Resource Locator
C) Universe Resultset Locator
D) Uniform Resultset Locator

Question 62

Used with the LIKE operator, the ______ symbol matches exactly one character.

A) _
B) %
C) ?
D) $

Question 63

To fetch a column in a result set that stores the number of children, use the ______ method.

A) nextInt()
B) getInt()
C) nextDouble()
D) getDouble()

Question 64

Beginners are afraid of issuing complex SQL queries, so they are ______

A) throwing away a major benefit of a relational database.
B) throwing an exception called badQueryException.
C) doing the right thing by avoiding those queries for efficiency.
D) taking advantage of the SQL benefits.

Question 65

What will the following expression match to?
Name LIKE 'e_%'

A) all strings in the Name column that have at least 3 characters.
B) all strings in the Name column whose first letter is an "e".
C) all strings in the Name column that start with the letter "e" and end with underscore.
D) all strings in the Name column whose second letter is any character.

Question 66

To fetch a column in a result set that stores prices, use the ______ method.

A) nextInt()
B) getInt()
C) nextDouble()
D) getDouble()

Question 67

What does the following statement do?
String prodCode = nextLine(in, "Product Code (D=Done, L=List)");

A) It will store the string "Product Code (D=Done, L=List)" in the variable in.
B) It will display "in, Product Code (D=Done, L=List)" on the screen.
C) It will display the contents of the variable in on the screen.
D) It will read the user's input and store it in the object prodCode.

Question 68

What will the following expression match to?
Name LIKE '%e%'

A) all strings in the Name column that end with "e".
B) all strings in the Name column whose second to last letter is an "e".
C) all strings in the Name column that contain the letter "e".
D) all strings in the Name column whose second letter is an "e".

Question 69

Database tables store rows that contain the following except

A) strings
B) fundamental data types
C) arbitrary objects
D) numbers

Question 70

The ______ clause is used to select data that fulfill a condition

A) SELECT
B) FROM
C) WHEN
D) WHERE

Question 71

"SQL injection attacks" have been responsible for many cases of data theft. One of the solutions is:

A) Never use double quotes in the query.
B) Never use single quotes in the query.
C) Never add a string to a query that you didn't type yourself.
D) Never add a number to a query that you didn't type yourself.

Question 72

What will the following expression match to?
Name LIKE '_e%'

A) all strings in the Name column that end with "e".
B) all strings in the Name column whose second to last letter is an "e".
C) all strings in the Name column that start with the letter "e".
D) all strings in the Name column whose second letter is an "e".

Question 73

To get the number of columns in a result set, you use _________ method of the ResultSetMetaData class.

A) getColumnInt()
B) getColumnsCount()
C) getCount()
D) getColumnCount()

Question 74

Which import statement will allow you to use a SQLException object?

A) import javax.swing.SQLException;
B) import java.sql.SQLException;
C) import java.util.SQLException;
D) import java.io.SQLException;

Question 75

Metadata are ______

A) data about an object.
B) the properties of a result set.
C) the objects that are used to execute the SQL commands.
D) data about a connection.