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优点是水位波动振幅小衰减快,需要调压室的容积小,且引水系统与其接头处的水头损失小;缺点是反射

水击波的效果较差的调压室是()。

A.简单圆筒式

B.阻抗式

C.溢流式

D.差动式

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第1题

WhichtypeofPL/SQLconstructwouldyouusetoautomaticallycorrecttheerrorresultingfromastatementthatwassuspendedduetoaspace-relatedproblem?()

A.functions

B.package

C.procedure

D.databasetrigger

E.anonymousPL/SQLblock

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第2题

Which two statements about Oracle Direct Network File System (NFS) are true?()

A. It bypasses the OS file system cache.

B. A separate NFS interface is required for use across Linux, UNIX, and Windows platforms.

C. It uses the operating system kernel NFS layer for user tasks and network communication modules.

D. File systems need not be mounted by the kernel NFS system when being served through Direct NFS.

E. Oracle Disk Manager can manage NFS on its own, without using the operating system kernel NFS driver.

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第3题

The OPTIMIZER_USE_PLAN_BASELINES parameter is set to TRUE. The optimizer generates a plan
for a SQL statement but does not find a matching plan in the SQL plan baseline.Which two operations are performed by the optimizer in this scenario?()

A. The optimizer adds the new plan to the plan history.

B. The optimizer selects the new plan for the execution of the SQL statement.

C. The optimizer adds the new plan to the SQL plan baseline as an accepted plan.

D. The optimizer adds the new plan to the SQL plan baseline but not in the ENABLED state.

E. The optimizer costs each of the accepted plans in the SQL plan baseline and picks the one with the lowest cost.

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第4题

Identitytwoadvantagesofusingarecoverycatalogin-loadofthecontrolFileofthetargetdatabaseRecoveryManager(RMAN).()

A.YoucanuseRMANstoredscripts.

B.Recoveryisfasterifdataisstoredincataloginadditiontothecontrolfile.

C.YoucanstorebackupInformationofallregistereddatabasesinoneplace.

D.Databasebackupsareautomaticallydeletedwhentheyareolderthanthespecifiedtimeperiod.

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第5题

Given:Which exception or error will be thrown when a programmer attempts to run this code?()

A.java.lang.StackOverflowError

B.java.lang.IllegalStateException

C.java.lang.ExceptionInInitializerError

D.java.lang.ArrayIndexOutOfBoundsException

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第6题

TheuserSCOTTexecutesthefollowingcommandsuccessfullytoincreasethesalaryvaluesinoneofhissess
ions:SQL>UPDATEempSETsal=sal*1.15WHEREdeptno=20BeforeSCOTTendsthetransaction,userHRwhohastheprivilegesonEMPtableexecutesaquerytofetchthesalarydetailsbutfindstheoldsalaryvaluesinsteadoftheincreasedvalues.WhydoesHRstillseetheolddata?()

A.becauseofredodatafromredologfile

B.becauseofdatafromdatabasebuffercache

C.becauseofdatafromatemporarytablespace

D.becauseofundodatafromtheundotablespace

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第7题

AdatabaseisrunningInARCHIVBXXMSmode.Ithas&
AdatabaseisrunningInARCHIVBXXMSmode.Ithastwoonlineredologgroupsandeachgrouphasonemember.

ALGWRInput/output(I/O)fellsduetopermanentmediafailurethathasresultedInthelossofredologfileandtheLWGRterminatescausingtheinstancetocrash.Thestepstorecoverfromthelossofacurrentredologgroupmemberintherandomorderareasfollow.

1)Restorethecorruptedredologgroup.

2)Restorefromawholedatabasebackup.

3)Performincompleterecovery.

4)Relocatebyrenamingthememberofthedamagedonlineredologgrouptoanewlocation.

5)OpenthedatabasewiththeRESETLOGSoption.

6)Restartthedatabaseinstance.

7)Issueacheckpointandclearthelog.

Identifytheoptionwiththecorrectsequentialstepstoaccomplishthetaskefficiently().

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第8题

Which statements are true regarding system-partitioned tables?()

A. Only a single partitioning key column can be specified.

B. All DML statements must use partition-extended syntax.

C. The same physical attributes must be specified for each partition.

D. Unique local indexes cannot be created on a system-partitioned table.

E. Traditional partition pruning and partitionwise joins are not supported on these tables.

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第9题

Notetheoutputofthefollowingquery;SQL>SELECTflashback_archieve_name,statusFROMdba_flashb
Notetheoutputofthefollowingquery;SQL>SELECTflashback_archieve_name,statusFROMdba_flashback_archieve;FLASHBACK_ARCHIEVE_NAMESTATUSFLA1YouexecutedthefollowingcommandtoenableFlashbackDataArchiveontheEXCHANGB_PATEtable:ALTERTABLEexchange_rateFLASHBACKARCHIEVE;Whatistheoutcomeofthiscommand?()

A.ThetableusesthedefaultFlashbackDataArchive.

B.TheFlashbackDataArchiveIscreatedIntheSYSAUXtablespace.

C.TheFlashbackDataArchiveiscreatedinthesametablespacewherethetablesarestored.

D.ThecommandgeneratesanerrorbecausenoflashbackDataArchivenameisspecifiedandthereis nodefaultFlashbackDataAchieve.

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第10题

Inyourproductiondatabase,youhaveobservedthatthedatabaseserverperformancedegradeswheneverth
Inyourproductiondatabase,youhaveobservedthatthedatabaseserverperformancedegradeswheneverthereisaswitchbetweentheloggroups.Onfurtherinvestigation,youfindthatthedatabaseisrunninginARCHIVELOGmodeandthearchivedlogfilesarebeingwrittentothesamediskthatisusedtostoretheredologmembers.Whichtwoactionswouldyoutaketoimprovetheperformanceofthedatabaseserver?()

A.increasethesizeoftheredologbuffer

B.increasethenumberofredologgroups

C.increasethenumberoflogwriterprocesses

D.increasethenumberofARCnprocesses

E.changetheappropriateLOG_ARCHIVE_DEST_nparametertoplacethearchivedlogfilesinaseparatelocation

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