Week 10

Question 1

The commands used to modify data is called what?

A. SQL
B. DDL
C. DML

Answer 1

C. DML (Data manipulation language)

Question 2

Match the following commands (A-H) with their descriptions (1-8).
A. INSERT 1. Allows ‘undoing’ uncommited changes
B. UPDATE 2. Adds data to/modifies existing rows
C. DELETE 3. Add new rows to table
D. COMMIT 4. Saves changed data permanently
E. ROLLBACK 5. Prevents others from making
changes to a table
F. SAVEPOINT 6. Creates shared lock to prevent
changes in specific columns
G. LOCK TABLE 7. Sets markers in a transaction
H. SELECT…FOR UPDATE 8. Removes rows

Answer 2

A. 3
B. 2
C. 8
D. 4
E. 1
F. 7
G. 5
H. 6

Question 3

______ must enclose nonnumeric data inserted in a column.

A. double quotes
B. single quotes
C. brackets

Answer 3

B. single quotes

Question 4

What are the ways to insert data with missing data for a column? (select all that apply)
A. List the columns after the table and omit that column name
B. Insert the word NULL where the column would be
C. Insert 2 double quotes where the column would be
D. Insert 2 single quotes where the column would be

Answer 4

A. List the columns after the table and omit that column name
B. Insert the word NULL where the column would be
D. Insert 2 single quotes where the column would be

Question 5

True/False: You can insert data for a virtual column.

Answer 5

False.

Question 6

If the string you need to enter has a single quote (O’hara) what must you do for it to correctly insert into the table?

A. Make is 2 single quotes
B. Nothing
C. Put double quotes around it
D. Remove the single quote to show as a single word instead

Answer 6

A. Make is 2 single quotes

Question 7

You can copy data from one table into another using what command?

A. COPY FROM
B. COPY INTO
C. INSERT INTO
D. INSERT FROM

Answer 7

C. INSERT INTO

Question 8

Choose the correct function to update a row.

A. UPDATE customer (lastname)
TO ‘smith’
WHERE lastname=’jones’;

B. UPDATE customer
IN lastname = ‘smith’
WHERE lastname = ‘jones’;

C. UPDATE customer
SET lastname = ‘smith’
WHERE lastname = ‘jones’;

Answer 8

C. UPDATE customer
SET lastname = ‘smith’
WHERE lastname = ‘jones’;

Question 9

When updating rows in a table, if the WHERE clause is missing what happens?

A. Throws an error
B. updates all rows with the table for the column
C. updates no rows in the table

Answer 9

B. updates all rows with the table for the column

Question 10

The substitution variable is used to substitute a value in place of the variable at the time of execution. What symbol is used for this?

A. &
B. #
C. %
D. @

Answer 10

A. &

Question 11

What command is issued to delete all records in a table?

Answer 11

DELETE FROM ;

Question 12

True/False: An implicit COMMIT occurs if you exit the client tools or a DDL command is issued.

Answer 12

True

Question 13

You use a _____ to create a checkpoint in a transaction where it can be rolled back to if something fails in the transaction.

A. CHECKPOINT
B. SAVEPOINT
C. BOOKMARK

Answer 13

B. SAVEPOINT

Question 14

In a ____ lock, users can view data in a table but they cannot alter the table structure or perform other DDL operations, or make changes to the row that is locked.

Answer 14

Shared

Question 15

If you need to place a shared lock on data you anticipate needs updating what command should you use?

A. LOCK ….FOR UPDATE
B. HOLD … FOR UPDATE
C. SELECT …. FOR UPDATE
D. Non of the above

Answer 15

C. SELECT …. FOR UPDATE

Question 16

If you want to restrict showing results for data based on the data that is in a column, what clause do you use?

Answer 16

WHERE

Question 17

If searching for part of a string or number, what symbol do you use as a wildcard to return all values with part of the string?

A. *
B. %
C. $
D. !

Answer 17

B. %
(EX: SELECT customer
FROM Name
Where name LIKE ‘SM%’;

Question 18

True/False: You can only use the >, < , = operator types on numerical data.

Answer 18

False

Question 19

If you are looking for data in a table where the number could be 5-9, what command could you use?

Answer 19

BETWEEN
(Ex: SELECT cost
FROM Book
Where cost BETWEEN 5 AND 9;

Question 20

If you are looking for data in a table where the state is specifically CA or GA, what command could you use?

Answer 20

IN
(Ex: SELECT state
FROM customers
WHERE state IN (‘GA’ , ‘CA’);

Question 21

You use the _____ operator with wildcard characters to search for patterns.

Answer 21

LIKE

Question 22

In using the LIKE operator what does the underscore (_) mean?

Answer 22

A single character is missing or you do not care what character it is.

Question 23

To sort output in an order what command do you use?

A. ORDER BY
B. LIST BY
C. SORT BY

Answer 23

A. ORDER BY

Question 24

True/False: You cannot order by more than one column at a time.

Answer 24

False