Week 9

Question 1

What language is used to create and modify tables?

A. data design language (ddl)
B. data information language (dil)
C. data definition language (ddl)
D. simple query language (sql)

Answer 1

C. data definition language (ddl)

Question 2

A variable length character data. the (n) is the maximum length.

A. VARCHAR2(n)
B. CHAR(n)
C.CHAR2(n)
D. NUMBER(n)

Answer 2

A. VARCHAR2(n)

Question 3

A fixed length character folumn. The (n) is the column length.

A. VARCHAR2(n)
B. CHAR(n)
C.CHAR2(n)
D. NUMBER(n)

Answer 3

B. CHAR(n)

Question 4

The p in NUMBER(p,s) stands for what? Select all that apply.

A. Precision
B. Percent
C. total number of digits
D. digits only to the left of the decimal

Answer 4

A. Precision

C. total number of digits

Question 5

The type of data Oracle12C is expected to store in a column is called what?

Answer 5

datatype

Question 6

How many columns can a table contain?

A. 100
B. 1000
C. 10000
D. none of the above

Answer 6

B. 1000

Question 7

True/False: When creating a table, columns should be enclosed in parenthesis.

Answer 7

True

Question 8

When creating a table, the columns must have what after the name to define them?

A. datatype
B. datafield
C. datadefinition
D. None of the above

Answer 8

A. datatype

Question 9

What command do you use to add rows after a table is created?

A. ADD
B. INSERT
C. CREATE RECORD

Answer 9

B. INSERT

Question 10

To view the stRucture of a table, what command do you use?

A. SHOW SCHEMA
B. DETAILS
C. DESCRIBE

Answer 10

C. DESCRIBE

Question 11

Choose the correct syntax for creating a table.

A. CREATE TABLE test
(ID CHAR(4)
name VARCHAR2(15)
bday DATE DEFAULT SYSDATE);

B. CREATE TABLE test
(ID CHAR(4),
name VARCHAR2(15),
bday DATE DEFAULT SYSDATE)

C. CREATE TABLE test
(ID CHAR(4),
name VARCHAR2(15),
bday DATE DEFAULT SYSDATE;

D. CREATE TABLE test
(ID CHAR(4),
name VARCHAR2(15),
bday DATE DEFAULT SYSDATE);

Answer 11

D. CREATE TABLE test
(ID CHAR(4),
name VARCHAR2(15),
bday DATE DEFAULT SYSDATE);

Question 12

The _____ data dictionary object maintains information on all your tables. Use it to show all the tables in your schema.

A. TABLES_DATA
B. USER_TABLES
C. USER_DATA
D. TABLES_USER

Answer 12

B. USER_TABLES

Question 13

The ___ TABLE command is used to modify tables.

A. ALTER
B. CHANGE
C. MODIFY

Answer 13

A. ALTER

Question 14

Using the ALTER TABLE ADD does what?

Answer 14

Adds a column

Question 15

To change the column definition after it’s already been created what syntax do you use?

A. ALTER TABLE CHANGE
B. ALTER TABLE FIX
C. ALTER TABLE MODIFY

Answer 15

C. ALTER TABLE MODIFY

Question 16

Which of the following are true of modifying existing columns?

A. it must be as wide as the data fields it already contains
B. Changes to a NUMBER column that already contains data will erase the data
C. You cannot decrease the precision or scale of a NUMBER column if it already contains data

Answer 16

A. it must be as wide as the data fields it already contains

C. You cannot decrease the precision or scale of a NUMBER column if it already contains data

Question 17

What command is used in creating a table or columns to set the date to the current date without the user inputting data?

Answer 17

SYSDATE

Question 18

To create a table from an existing table what command do you use?

A. CREATE FROM
B. CREATE TABLE…AS
C. NEW TABLE…AS
D. NEW TABLE FROM

Answer 18

B. CREATE TABLE…AS

Question 19

Use the ALTER TABLE _____ COLUMN to delete an existing column from a table.

A. DROP
B. DELETE
C. REMOVE
D. ERASE

Answer 19

A. DROP

Question 20

You cannot remove what two types of columns from a table?

Answer 20

Primary key column

last column in the table

Question 21

The SET UNUSED command is used to what? It makes the data in the column unavailable.

Answer 21

Marks it for deletion at another time.
Useful to use in production environments if you want the data to be ‘gone’ but you do not want the server to process it until a time there is less load on the server.

Question 22

True/False: You can query a table based on it’s old name if you used the RENAME command.

Answer 22

False

Question 23

If you want to remove all the records (rows) in a table, but keep the columns, what command would you use?

A. REMOVE ALL
B. DELETE * ROWS
C. TRUNCATE TABLE
D. TRUNCATE RECORDS

Answer 23

C. TRUNCATE TABLE

Question 24

The DROP TABLE command does what?

Answer 24

Deletes an entire table, structure and data.

Question 25

True/False: After using the DROP TABLE command, it can be recovered from a recycle bin.

Answer 25

True

Question 26

What command is used to restore a table after it was deleted?

A. FLASHBACK TABLE
B. RESTORE TABLE
C. RECREATE TABLE

Answer 26

A. FLASHBACK TABLE

Question 27

Use the ____ TABLE to remove it from the recycle bin.

A. DELETE
B. REMOVE
C. ERASE
D. PURGE

Answer 27

D. PURGE

Question 28

What constraint type cannot be created at the table level?

Answer 28

NOT NULL

Question 29

True/False: If a data value violates a constraint, the entire row is rejected

Answer 29

True

Question 30

True/False: You can delete a value in a parent table if it is referenced by a child table? (foreign keys)

Answer 30

No

If a value is referenced in another table, it cannot be deleted.

Question 31

What command is used to automatically set a parent row value to delete if the foreign key value is deleted in a child table?

A. ON DELETE REPLICATE
B. ON DELETE CASCADE
C. ON DELETE PARENT
D. ON DELETE PURGE

Answer 31

A. ON DELETE REPLICATE

Question 32

The _____ constraint is used to verify another condition is true before accepting input.

A. VERIFY
B. CHECK
C. UNIQUE

Answer 32

B. CHECK

Question 33

What command is used to display constraint listing for a specific table?

Answer 33

USER_CONSTRAINTS

Question 34

Use the ____ command to stop using a constraint.

Answer 34

DISABLE