Database - Managing Databases with Oracle MCQs Part

1. What type of failure occurs when Oracle fails due to an operating system or computer hardware failure?

A.
Application failure
B.
Instance Failure
C.
Media Failure
D.
Rollback failure

 Answer Option B

2. Which statement about sequences is not true?

A.
A sequence is an object that generates a sequential series of unique numbers.
B.
Sequences are most often used to provide values for surrogate keys.
C.
NextVal and CurrVal are both sequence methods.
D.
Sequences guarantee valid surrogate key values.

 Answer Option D

3. Which prefixes are available to Oracle triggers?

A.
:new only
B.
:old only
C.
Both :new and :old
D.
Neither :new nor :old

 Answer Option C

4. In creating a procedure, you may get a message if you have compile errors. Which of the following is true?

A.
The line numbers reported match the line numbers you see in your text editor.
B.
SQL*Plus will automatically show the errors to you.
C.
To see the errors, enter SHOW ERRORS in SQL*Plus.
D.
If there are no syntax errors, you will receive the message "NO ERRORS."

 Answer Option C

5. Which of the following is not true about indexes?

A.
Indexes are created to enforce uniqueness on columns.
B.
Indexes are created to enable fast retrieval by column values.
C.
Columns that are frequently used with equal conditions in WHERE clauses are good candidates for indexes.
D.
Indexes are created with the ALTER TABLE command.

 Answer Option D

6. Which of the following is not true of SQL views?

A. Oracle views cannot use the ORDER BY clause in view definitions.
B. Oracle views are created using the standard SQL-92 CREATE VIEW command.
C. Oracle views can by queried.
D. The SQL-92 standard does not allow the use of the ORDER BY clause in view definitions.

 Answer Option A

7. SQL*Plus will finish the statement and execute it when the user types in this:

A. A left slash ( \ ) followed by [Enter].
B. A colon ( : ) followed by [Enter].
C. A semicolon ( ; ) followed by [Enter].
D. A period ( . ) followed by [Enter].

 Answer Option C

8. Which of the following is NOT an Oracle-supported trigger?

A. BEFORE
B. DURING
C. AFTER
D. INSTEAD OF

 Answer Option B

9. After a table has been created, its structure can be modified using the SQL command:

A. UPDATE TABLE [TableName].
B. MODIFY TABLE [TableName].
C. ALTER TABLE [TableName].
D. CHANGE TABLE [TableName].

 Answer Option C

10. Which of the following is not true about modifying table columns?

A. You can drop a column at any time.
B. You can add a column at any time as long as it is a NULL column.
C. You can increase the number of characters in character columns or the number of digits in numeric columns
D. You cannot increase or decrease the number of decimal places.

 Answer Option D

11. Of the three ways to create an Oracle database, which one is the easiest and most recommended?

A. Using the Oracle Database Configuration Assistant.
B. Using the Oracle-supplied database creation procedures.
C. Using the SQL CREATE DATABASE command.
D. None of the above is correct.

 Answer Option A

12. What Oracle backup and recover file contains user and system data?

A. Control file
B. Datafile
C. OnLine ReDo file
D. Offline ReDo file

 Answer Option B

13. When using SQL*Plus, Oracle commands, column names, table names and all other database elements:

A. are case insensitive.
B. are case sensitive.
C. must always be in lower case.
D. must always be in upper case.

 Answer Option A

14. Which SQL phrase is not supported by Oracle?

A. ON DELETE CASCADE
B. ON UPDATE CASCADE
C. CREATE SEQUENCE [SequenceName]
D. DROP SEQUENCE [SequenceName]

 Answer Option B

15. What is the type of Oracle backup in which all uncommitted changes have been removed from the datafiles?

A. Full backup
B. Consistent backup
C. Inconsistent backup
D. Differential backup

 Answer Option B

16. You have linked SQL*Plus to an external text editor. To invoke the text editor for use within SQL*Plus, which command do you use?

A. Open [FileName]
B. Show [FileName]
C. Alter [FileName]
D. Edit [FileName]

 Answer Option D

17. The default extension for an Oracle SQL*Plus file is:

A. .txt.
B. .pls.
C. .ora.
D. .sql.

 Answer Option D

18. An Oracle System Change Number (SCN):

A. is a value that is incremented whenever a dirty read occurs.
B. is incremented whenever a deadlock occurs.
C. is a value that keeps track of explicit locks.
D. is a value that is incremented whenever database changes are made.

 Answer Option D

19. To obtain the structure of an Oracle table, the command to use is:

A. STRUCTURE [TableName].
B. DESCRIBE [TableName].
C. DESCRIBE STRUCTURE [TableName].
D. DESC TABLE [TableName].

 Answer Option B

20. To see the contents of the SQL*Plus buffer, type:

A. CONTENTS.
B. BUFFER.
C. CURRENT.
D. LIST.

 Answer Option D

6. Which of the following is not true of SQL views?

A. Oracle views cannot use the ORDER BY clause in view definitions.
B. Oracle views are created using the standard SQL-92 CREATE VIEW command.
C. Oracle views can by queried.
D. The SQL-92 standard does not allow the use of the ORDER BY clause in view definitions.

 Answer Option A

7. SQL*Plus will finish the statement and execute it when the user types in this:

A. A left slash ( \ ) followed by [Enter].
B. A colon ( : ) followed by [Enter].
C. A semicolon ( ; ) followed by [Enter].
D. A period ( . ) followed by [Enter].

 Answer Option C

8. Which of the following is NOT an Oracle-supported trigger?

A. BEFORE
B. DURING
C. AFTER
D. INSTEAD OF

 Answer Option B

9. After a table has been created, its structure can be modified using the SQL command:

A. UPDATE TABLE [TableName].
B. MODIFY TABLE [TableName].
C. ALTER TABLE [TableName].
D. CHANGE TABLE [TableName].

 Answer Option C

10. Which of the following is not true about modifying table columns?

A. You can drop a column at any time.
B. You can add a column at any time as long as it is a NULL column.
C. You can increase the number of characters in character columns or the number of digits in numeric columns
D. You cannot increase or decrease the number of decimal places.

 Answer Option D

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