单项选择题Which statement is true regarding the COALESCE function?()

A.It can have a maximum of five expressions in a list 
B.It returns the highest NOT NULL value in the list for all rows 
C.It requires that all expressions in the list must be of the same data type 
D.It requires that at least one of the expressions in the list must have a NOT NULL value


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1.单项选择题What does the minimize load database parameter mean when backing up a database?()

A.RMAN will attempt to make the backup run as fast as possible without any IO limitations. 
B.RMAN will automatically restrict the number of channels in use to one. 
C.RMAN will spread the backup IO over the total duration stated in the backup command.
D.RMAN will skip any datafile that currently is involved in an IO operation. RMAN will retry backing up the datafile later and an error will be raised at the end of the backup if the datafile cannot be backed up. 
E.Datafiles will be backed up; those having the lowest current number of IO operations will be backed up first. 

2.单项选择题What view might you use to try to determine how long a particular backup will take?()

A.V$SESSION_EVENT 
B.V$SESSION 
C.V$W0041ITS
D.V$WAITSTAT 
E.V$SESSION_LONGOPS 

3.单项选择题What does it mean if a backup is expired?()

A.The backup set has exceeded the retention criteria set in RMAN and is eligible for removal. 
B.The backup set has one or more invalid blocks in it and is not usable for recovery. 
C.The backup set contains one or more tablespaces no longer in the database.  
D.The backup set contains one or more missing backup set pieces.
E.The backup set is from a previous version of RMAN and was not upgraded. 

4.单项选择题You want to make sure that your database backup does not exceed 10 hours in length. What command would you issue that would meet this condition?()

A.backup database plus archivelog
B.backup database plus archivlog until time ‘10:00‘
C.backup database plus archivelog timeout ‘10:00‘
D.backup database plus archivelog duration 10:00

6.单项选择题Which command would you use to determine what database backups are currently available for restore?()

A.list database backup
B.report database backup  
C.list backup of database
D.list summary backup
E.report backup of database

7.单项选择题You are using RMAN to backup your ARCHIVELOG mode database. You have enabled control-file autobackups. Which files are not backed up during the RMAN backup?()

A.Database Datafiles 
B.Database Control Files 
C.Online redo logs
D.Archived redo logs 
E.The database SPFILE 
F.None of the above, all these files are backed up. 

8.单项选择题Which command will restore all datafiles to the date 9/30/2008 at 18:00 hours? ()

A.restore datafiles until time '09/28/2008:21:03:11'
B.restore database files until time '09/28/2008:18:00:00'
C.restore database until time '09/28/2008:18:00:00'
D.recover database until time '09/28/2008:18:00:00'
E.recover database until timestamp '09/28/2008:18:00:00'

9.单项选择题What command would you issue to enable automated backups of control files? ()

A.alter database controlfile autobacku on
B.alter system controlfile autobackup on 
C.configure controlfile autobackup on 
D.enable controlfile autobackup

10.单项选择题Which command do you use to create a recovery-catalog schema? ()

A.create recovery catalog 
B.create catalog
C.build catalog 
D.catalog create 
E.mount catalog 

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Note the following statements that use flashback technology:1. FLASHBACK TABLE <table> TO SCN <scn>;2. SELECT * FROM <table> AS OF SCN 123456;3. FLASHBACK TABLE <table> TO BEFORE DROP;4. FLASHBACK DATABASE TO TIMESTAMP <timestamp>;5. SELECT * FROM <table> VERSIONS AS OF SCN 123456 AND 123999;Which of these statements will be dependent on the availability of relevant undo data in the undo segment?()

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Which three functions are performed by the SQL Tuning Advisor? ()

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