Database

Database

Managing Databases with Oracle has 40 Questions

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

Application failure
Instance Failure
Media Failure
Rollback failure
Indexes are created to enforce uniqueness on columns and to enable fast retrieval by column values.

True
False
Which statement about sequences is not true?

A sequence is an object that generates a sequential series of unique numbers.
Sequences are most often used to provide values for surrogate keys.
NextVal and CurrVal are both sequence methods.
Sequences guarantee valid surrogate key values.
Money is defined in Oracle with the Currency data type.

True
False
Which prefixes are available to Oracle triggers?

:new only
:old only
Both :new and :old
Neither :new nor :old
The default extension for SQL*Plus is .sql.

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

The line numbers reported match the line numbers you see in your text editor.
SQL*Plus will automatically show the errors to you.
To see the errors, enter SHOW ERRORS in SQL*Plus.
If there are no syntax errors, you will receive the message "NO ERRORS."
The left-leaning slash tells Oracle to execute whatever statement is in the buffer.

True
False
Which of the following is not true about indexes?

Indexes are created to enforce uniqueness on columns.
Indexes are created to enable fast retrieval by column values.
Columns that are frequently used with equal conditions in WHERE clauses are good candidates for indexes.
Indexes are created with the ALTER TABLE command.
Oracle maintains a System Change Number (SCN) which is a database-wide value that is incremented by Oracle whenever database changes are made.

True
False
Which of the following is not true of SQL views?

Oracle views cannot use the ORDER BY clause in view definitions.
Oracle views are created using the standard SQL-92 CREATE VIEW command.
Oracle views can by queried.
The SQL-92 standard does not allow the use of the ORDER BY clause in view definitions.
The semicolon terminates a SQL statement (and executes it).

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

A left slash ( ) followed by [Enter].
A colon ( : ) followed by [Enter].
A semicolon ( ; ) followed by [Enter].
A period ( . ) followed by [Enter].
SQL*Plus is a text editor.

True
False
Which of the following is NOT an Oracle-supported trigger?

BEFORE
DURING
AFTER
INSTEAD OF
When you type Start FILENAME, the statement in your file will be executed automatically.

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

UPDATE TABLE [TableName].
MODIFY TABLE [TableName].
ALTER TABLE [TableName].
CHANGE TABLE [TableName].
You can check on the status of tables with the DESCRIBE or DESC command.

True
False
Which of the following is not true about modifying table columns?

You can drop a column at any time.
You can add a column at any time as long as it is a NULL column.
You can increase the number of characters in character columns or the number of digits in numeric columns
You cannot increase or decrease the number of decimal places.
Oracle directly supports the definition of surrogate keys.

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

Using the Oracle Database Configuration Assistant.
Using the Oracle-supplied database creation procedures.
Using the SQL CREATE DATABASE command.
None of the above is correct.
When you type into SQL*Plus and press enter, the statement will be finished and executed.

True
False
What Oracle backup and recover file contains user and system data?

Control file
Datafile
OnLine ReDo file
Offline ReDo file
Oracle allows the ORDER BY clause in view definitions.

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

are case insensitive.
are case sensitive.
must always be in lower case.
must always be in upper case.
Oracle does NOT support a CASCADE UPDATE constraint.

True
False
Which SQL phrase is not supported by Oracle?

ON DELETE CASCADE
ON UPDATE CASCADE
CREATE SEQUENCE [SequenceName]
DROP SEQUENCE [SequenceName]
Sequences guarantee valid surrogate key values.

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

Full backup
Consistent backup
Inconsistent backup
Differential backup
Oracle will let you define Notepad as your default editor, and whenever you type NOTEPAD, SQL*Plus will invoke Notepad.

True
False
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?

Open [FileName]
Show [FileName]
Alter [FileName]
Edit [FileName]
Oracle commands, column names, table names, view names and all other database elements are case sensitive.

True
False
The default extension for an Oracle SQL*Plus file is:

.txt.
.pls.
.ora.
.sql.
If there is only one statement and no ambiguity about what is wanted, Oracle will treat the semicolon and slash as the same.

True
False
An Oracle System Change Number (SCN):

is a value that is incremented whenever a dirty read occurs.
is incremented whenever a deadlock occurs.
is a value that keeps track of explicit locks.
is a value that is incremented whenever database changes are made.
The only time that case matters is inside quotation marks of strings.

True
False
To obtain the structure of an Oracle table, the command to use is:

STRUCTURE [TableName].
DESCRIBE [TableName].
DESCRIBE STRUCTURE [TableName].
DESC TABLE [TableName].
You can use the DROP statement to remove structures from the database.

True
False
To see the contents of the SQL*Plus buffer, type:

CONTENTS.
BUFFER.
CURRENT.
LIST.
Oracle, the world's most popular DBMS, is powerful and robust, running on many different operating systems.

True
False