单项选择题

Two database users, Jack and Bill, are accessing the Certkiller STAFF table of the Certkiller DB database. When Jack modifies a value in the table, the new value is invisible to Bill. 
Which is the modified value invisible to Bill?()

A.The modified data are not available on disk.
B.The modified data have been flushed out from memory.
C.The modified rows of the Certkiller STAFF table have been locked.
D.Jack has not committed the changes after modifying the value.
E.Both users are accessing the database from two different machines.


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1.单项选择题

You work as a database administrator for Certkiller .com. As a result of performance analysis, you created an index on theprod_namecolumn of the 
Certkiller prodtable, which contains about ten thousand rows. Later, you updated a product name in the table. 
How does this change affect the index?()

A.A leaf will be marked as invalid.
B.An update in a leaf row takes place.
C.The index will be updated automatically at commit.
D.A leaf row in the index will be deleted and inserted.
E.The index becomes invalid when you make any updates

3.单项选择题

You are working on the Certkiller database. 
What is the default name of the alert log file in this database?()

A.alert_ Certkiller .log
B.alertlog_ Certkiller .log
C.alert_log_ Certkiller .log
D.Certkiller _alert_log.log
E.log_alert_: Certkiller .log
F.trace_alert_ Certkiller .log

5.单项选择题You work as a database administrator for Certkiller .com. The database is open. A media failure has occurred, resulting in loss of all the control files in your database. Which statement regarding the database instance is true in this scenario?()

A.The instance would hang.
B.The instance needs to be shut down.
C.The instance would be in the open state.
D.The instance would abort in such cases.
E.The instance would be in the open and invalid state.
F.The instance would in the open state, but all the background processes will be restarted.

6.多项选择题You are working on a test database where instance recovery takes a considerable amount of time.How can reduce the recovery time?()

A.By multiplexing the control files
B.By multiplexing the redo log files
C.By decreasing the size of redo log files
D.By configuring mean time to recover (MTTR) to a lower value
E.By setting the UNDO_RETENTION parameter to a higher value

9.单项选择题In your Certkiller .com database server the parameter PLSQL_CODE_TYPE has been set to NATIVE. Which object would be achieved by the setting?()

A.The source PL/SQL code will be stored in native machine code.
B.The source PL/SQL code will be stored in interpreted byte code.
C.The compiled PL/SQL code will be stored in native machine code.
D.The compiled PL/SQL code will be stored in interpreted byte code.

10.单项选择题You work as a database administrator for Certkiller .com. On a Monday morning, you find the database instance aborted. After inspecting the alert log file, you execute the STARTUP command in SQL*Plus to bring the instance up. What statement is true?()

A.PMON coordinates media recovery.
B.SMON coordinates instance recovery.
C.PMON coordinates instance recovery.
D.Undo Advisor would roll back all uncommitted transactions.
E.SQL*PLUS reports an error with the message asking you to perform instance recovery. 

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