2024年Oracle认证笔试历年真题荟萃含答案

2024年Oracle认证笔试历年真题荟萃含答案（图片大小可自由调整）答案解析附后卷I一.参考题库(共25题)1.Which two statements are true about a job chain？（）A、 A job chain can contain a nested chain of jobsB、 The jobs in a job chain cannot have more than one dependencyC、 A job of the CHAIN type can be run using event-based or time-based schedulesD、 The jobs in a job chain can be executed only by using the events generated by the Scheduler2.WhichtwostatementsaretrueaboutWHEREandHAVINGclauses?（）A、AWHEREclausecanbeusedtorestrictbothrowsandgroups.B、AWHEREclausecanbeusedtorestrictrowsonly.C、AHAVINGclausecanbeusedtorestrictbothrowsandgroups.D、AHAVINGclausecanbeusedtorestrictgroupsonly.E、AWHEREclauseCANNOTbeusedinaqueryofthequeryusesaHAVINGclause.F、AHAVINGclauseCANNOTbeusedinsubqueries.3.Given： What is the result？（）A、Afoo AfooB、Afoo BfooC、Bfoo AfooD、Bfoo BfooE、Compilation fails4.User SCOTT wants to export his objects using Oracle Data Pump and executes the following command： $ expdp scott/tiger  directory = EXPORT_DIR  dumpfile = scott.dmp include = table  include = view："like ’%DEPARTMENTS%’"  content = DATA_ONLY  Which task would the command accomplish？（）A、AB、BC、CD、DE、E5.What is the implication of this command?（）A、The command produces an error because the retention time cannot be reduced. B、All historical data is retained but the subsequent flashback data archives are maintained for only three years. C、All historical data is purged and the new flashback data archives are maintained for three years. D、All historical data older than three years is purged from the flashback archive FLA1. 6.You are managing an Oracle Database 11g database. You want to take the backup of MULT_DATA， a big file tablespace of size 100 TB on tape drive， but you have tapedrives of only 10 GB each.  Which method would accomplish the task quickly and efficiently？（）  A、 parallel image copy backupB、 backup with MAXPIECESIZE configured for the channelC、 parallel backup with MAXPIECESIZE configured for the channeD、 intrafile parallel backup7.You work as a database administrator for S. One of the database users accidentally deleted all the rows of a critical table and committed the delete at 1：30 p.m. You senior database administrator， SupportCenter， asks you to retrieve the lost data. Which two actions would you use to ensure that there is no impact on other connected users while retrieving the deleted rows？（）A、Use a flashback query to retrieve the rows that were deletedB、Useconventialincremental export and then import the affected objectC、Shutdown the database inNORMALmode and restart the database instanceD、Use DBMS_META package to reconstruct the object using undo segmentsE、UseTablespacePoint in Time Recovery （TSPITR） method to recover the table and the dataF、Use Oracle DataPumptwithflashback_timeoption toentableflashback export and then import the affected object.8.TheCUSTOMERStablehasthesecolumns: WhichstatementfindstherowsintheCUSTOMERStablethatdonothaveapostalcode?（）A、SELECTcustomer_id,customer_name

FROMcustomers

WHEREpostal_codeCONTAINSNULL;B、SELECTcustomer_id,customer_name

FROMcustomers

WHEREpostal_code='________';C、SELECTcustomer_id,customer_name

FROMcustomers

WHEREpostal_codeISNULL;D、SELECTcustomer_id,customer_name

FROMcustomers

WHEREpostalcodeISNVL;E、SELECTcustomer_id,customer_name

FROMcustomers

WHEREpostal_code=NULL;9.YouexecutethefollowingstatementinaMicrosoftWindowsenvironment.Therearenoconflictsinthepathnamedefinitions. C:/＞mysqld–installMysql56–defaults–file=C:/my–fWhatistheexpectedoutcome?（）A、MysqlisinstalledastheWindowsservicenameMysql56,andusesc:/fastheconfigurationfileB、Anerrormessageisissuedbecause–installisnotavalidoptionformysqldC、ArunningMysql5.6installationhasitsruntimeconfigurationupdatedwiththeservervariablessetinc:/fD、MysqldactsasanMSIinstallerandinstallstheMysql5.6version,withthec:/fconfigurationfile10.Which four service offerings are included in Oracle Public Cloud?（）A、 Database ServiceB、 Data ServiceC、 Java ServiceD、 Security ServiceE、 .NET ServiceF、 SOA Service11.The SCOTT user has an index on the ITEM_DESC column of the ITEM table. As part of the year-ending task， SCOTT updates the ITEM_DESC column for most of the rows in the ITEM table. How does this change to the table affect the index？（）A、An update in a leaf row takes place.B、The index becomes invalid after the update.C、The leaf block containing the row to be updated is marked as invalid.D、A row in the leaf block of the index for the key value is deleted and inserted.12.Whichobjectprivilegescanbegrantedonaview?（）A、noneB、DELETE,INSERT,SELECTC、ALTER,DELETE,INSERT,SELECTD、DELETE,INSERT,SELECT,UPDATE13.WhichtasksarerunautomaticallyaspartoftheAutomatedMaintenanceTaskbydefault?（）A、SegmentAdvisorB、SQLAccessAdvisorC、OptimizerstatisticsgatheringD、AutomaticSQLTuningAdvisorE、AutomaticDatabaseDiagnosticsMonitor14.ExaminethestructureoftheEMPLOYEESandDEPARTMENTStables: EMPLOYEES EMPLOYEE_IDNUMBER DEPARTMENT_IDNUMBER MANAGER_IDNUMBER LAST_NAMEVARCHAR2(25) DEPARTMENTS DEPARTMENT_IDNUMBER MANAGER_IDNUMBER DEPARTMENT_NAMEVARCHAR2(35) LOCATION_IDNUMBER Youwanttocreateareportdisplayingemployeelastnames,departmentnames,andlocations.Whichqueryshouldyouusetocreateanequi-join?（）A、SELECTlast_name,department_name,location_idFROMemployees,department;B、SELECTemployees.last_name,departments.department_name,departments.location_idFROMemployeese,departmentsDWHEREe.department_id=d.department_id;C、SELECTe.last_name,d.department_name,d.location_idFROMemployeese,departmentsDWHEREmanager_id=manager_id;D、SELECTe.last_name,d.department_name,d.location_idFROMemployeese,departmentsDWHEREe.department_id=d.department_id;15.Oracle的数据操纵包括（）。A、数据查询操作B、数据更新操作C、数据删除操作D、数据插入操作16.You receive the following error：   ORA-19804： cannot reclaim nnnnn bytes disk space from mmmmm limit   Identify the reason for receiving the above error message？（）A、 The sort area is very small.B、 There is no more space in the Undo tablespace.C、 The flash recovery area is full.D、 The online redo log file is full.17.TheEMPLOYEEStablecontainsthesecolumns: LAST_NAMEVARCHAR2(25) SALARYNUMBER(6,2) COMMISSION_PCTNUMBER(6) Youneedtowriteaquerythatwillproducetheseresults: 1.Displaythesalarymultipliedbythecommission_pct. 2.Excludeemployeeswithazerocommission_pct. 3.Displayazeroforemployeeswithanullcommissionvalue. EvaluatetheSQLstatement: SELECTLAST_NAME,SALARY*COMMISSION_PCT FROMEMPLOYEES WHERECOMMISSION_PCTISNOTNULL; Whatdoesthestatementprovide?（）A、AllofthedesiredresultsB、TwoofthedesiredresultsC、OneofthedesiredresultsD、Anerrorstatement18.You are maintaining the PROD database for NetFx Corporation. You have configured controlfile autobackup in your database. At 6：00 P.M. on Monday， you issue the following command：       RMAN>BACKUP DATABASE；  At 8：00 A.M. on Tuesday， you are unable to start the database because all the control files are missing. You decide to restore the control files from the backup by using the RMAN> RESTORE CONTROLFILE FROM AUTOBACKUP； command. Which operation should you perform before using the RMAN> RESTORE CONTROLFILE FROM AUTOBACKUP； command？（）A、 Start the database in the MOUNT stage.B、 Back up the control file to trace.C、 Set the DBIDD、 Issue the RECOVER DATABASE command.19.You want to rebuild a free list in the free lists of the EMPLOYEE table in the Scott schema. Which package will you use to accomplish this？（）A、 DBMS_REPAIRB、 DBMS_SCHDULERC、 DBMS_STATSD、 DBMS_RESOURCE_MANAGER20.What is the result of this command？（） RMAN> Report need backup days 3；A、 Lists all datafiles created in the last three days that are not backed up.B、 Lists all datafiles not recoverable based on the current retention criteria.C、 Lists all datafiles not backed up in the last three days. The datafile is not recoverable. D、 Lists all datafiles that need to be backed up due to unrecoverable operations.E、 Lists all datafiles not backed up in the last three days. It does not imply that the datafile is not recoverable.21.To clean up old records that are in a Flashback Data Archive and are past the retention period， what must the DBA do？（）  A、 TRUNCATE the archive table.B、 DROP the Flashback Data Archive.C、 Nothing；expired rows are automatically removed.D、 Nothing；expired rows are moved to an archive table.E、 Delete entries from the archive where the metadata date retained is greater than the retention period.22.A user is running a long update batch file. Many tables are updated and all the  statements are in one transaction. Before the process is finished， the user machine lost power. When the user calls you， what should you do as DBA？（）A、AB、BC、CD、D23.授予sa用户在SCOTT.EMP表中SAL列的更新权限的语句是（）。A、GRANTCHANGEONSCOTT.EMPTOSAB、GRANTUPDATEONSCOTT.EMP（SAL）TOSAC、GRANTUPDATE（SAL）ONSCOTT.EMPTOSAD、GRANTMODIFYONSCOTT.EMP（SAL）TOSA24.You work as a database administrator for S. Users in the S PROD database complain about the slow response of transactions. While investigating the reason you find that the transactions are waiting for the undo segments to be available， and undo retention has been set to zero.  What would you do to overcome this problem？（）A、Increase the undo returnB、Create more undo segmentsC、Create another undotablespaceD、Increase the size of the undo tablespace25.YoudatabaseisrunninganARCHIVELOGmode. Thefollowingparameteraresetinyourdatabaseinstance: LOG_ARCHIVE_FORMAT=arch+%t_%r.arc LOG_ARCHIVE_DEST_1=‘LOCATION=/disk1/archive’ DB_RECOVERY_FILE_DEST_SIZE=50G DB_RECOVERY_FILE=‘/u01/oradata’ Whichstatementistrueaboutthearchivedredologfiles?（）A、TheyarecreatedonlyinthelocationspecifiedbytheLOG_ARCHIVE_DEST_1parameter.B、TheyarecreatedonlyintheFastRecoveryArea.C、TheyarecreatedinthelocationspecifiedbytheLOG_ARCHIVE_DEST_1parameterandinthedefaultlocation$ORACLE_HOME/dbs/arch.D、TheyarecreatedinthelocationspecifiedbytheLOG_ARCHIVE_DEST_1parameterandthelocationspecifiedbytheDB_RECOVERY_FILE_DESTparameter.卷II一.参考题库(共25题)1.Aclass games.cards.Poker is correctly defined in the jar file Poker.jar. A user wants to execute the main method of Poker on a UNIX system using the command：java games.cards. PokerWhat allows the user to do this？（）A、put Poker.jar in directory /stuff/java， and set the CLASSPATH to include /stuff/javaB、put Poker.jar in directory /stuff/java， and set the CLASSPATH to include /stuff/java/*.jarC、put Poker.jar in directory /stuff/java， and set the CLASSPATH to include /stuff/java/Poker.jarD、put Poker.jar in directory /stuff/java/games/cards， and set the CLASSPATH to include /stuff/java2.ExaminethestructureoftheEMPLOYEEStable: EMPLOYEE_IDNUMBERPrimaryKey FIRST_NAMEVARCHAR2(25) LAST_NAMEVARCHAR2(25) HIRE_DATEDATE WhichINSERTstatementisvalid?（）A、INSERTINTOemployees(employee_id,first_name,last_name,hire_date)VALUES(1000,'John','smith','01/01/01);B、INSERTINTOemployees(employee_id,first_name,last_name,hire_date)VALUES(1000,'John','smith','01january01');C、INSERTINTOemployees(employee_id,first_name,last_name,Hire_date)VALUES(1000,'John','smith',To_date('01/01/01));D、INSERTINTOemployees(employee_id,first_name,last_name,hire_date)VALUES(1000,'John','smith','01-Jan-01');3.TapestreamingisnothappeningwhileperformingRMANtapebackup.Oninvestigation,youfindthatitisnotbecauseoftheincrementalbackuportheemptyfilebackupandthatRMANissendingdatablockstothetapedrivefastenough. Whatcouldbeasolutiontomaketapestreaminghappenduringthebackup?（）A、ConfigurebackupoptimizationB、ConfigurethechanneltoincreaseMAXOPENFILESC、ConfigurethechanneltoincreasethecapacitywiththeRATEparameterD、ConfigurethechanneltoadjustthetapebuffersizewiththeBLKSIZEoption4.You executed the following command in Recovery Manager （RMAN）：  RMAN> RESTORE CONTROLFILE；  Which operation must you perform before this command is executed？（） A、back up the control file to traceB、bring database to the MOUNT stateC、open a connection to the RMAN recovery catalog， which contains the RMAN metadata for the target databaseD、set the database ID （DBID）， but only if the DB_NAME parameter associated with the target database is unique in the recovery catalog5.Which built-in copies values from a record group into a list item? （）A、POPULATE_LIST B、POPULATE_GROUP C、POPULATE_LIST_ITEM D、POPULATE_LIST_FROM_GROUP E、POPULATE_LIST_ITEM_FROM_GROUP6.DRAGDROPClicktheTaskbutton. 7.WhichthreearetrueaboutthelargepoolforanOracledatabaseinstancethatsupportssharedserverconnections?（）A、AllocatesmemoryforRMANbackupandrestoreoperationsB、AllocatesmemoryforsharedandprivateSQLareasC、ContainsacursorareaforstoringruntimeinformationaboutcursorsD、ContainsstackspaceE、Containsahashareaperforminghashjoinsoftables8.YouareusingRecoveryManager(RMAN)witharecoverycatalogtobackupyourproductiondatabase.Thebackupsandthearchivedredologfilesarecopiedtoatapedriveonadailybasis.Becauseofmediafailure,youlostyourproductiondatabasecompletelyalongwiththerecoverycatalogdatabase.Youwanttorecoverthetargetdatabaseandmakeitfunctional.Youconsiderperformingthefollowingstepstoaccomplishthetask: Whichoptionillustratesthecorrectsequencethatyoumustuse?（）A、8,1,3,2,4,5,7,6B、1,8,3,4,2,5,7,6C、1,3,4,2,8,5,6,7D、1,3,2,4,6,5,7,89.（）可用于返回会话中的日期和时间。A、months_between（）B、next_day（）C、current_date（）D、localtimestamp（）10.TheEMPLOYEEStablehasthesecolumns: ManagementwantstoaddadefaultvaluetotheSALARYcolumn.YouplantoalterthetablebyusingthisSQLstatement: WhatistrueaboutyourALTERstatement?（）A、ColumndefinitionscannotbealteredtoaddDEFAULTvalues.B、AchangetotheDEFAULTvalueaffectsonlysubsequentinsertionstothetable.C、ColumndefinitionscannotbealteredataddDEFAULTvaluesforcolumnswithaNUMBERdatatype.D、AlltherowsthathaveaNULLvaluefortheSALARYcolumnwillbeupdatedwiththevalue5000.11.While designing the database for one of your online transaction processing （OLTP） applications， you want to achieve the following：  a） high availability of data  b） faster primary key access to the table data  c） compact storage for the table  Which type of tables would you use to achieve these objectives？（）A、 heap tablesB、 object tablesC、 partitioned tablesD、 index-organized tables （IOTs）12.哪一个表空间不能切换为脱机状态（）A、临时表空间TEMPB、用户表空间USERC、索引表空间INDEXD、系统表空间SYSTEM13.Whichtwostatementscompleteatransaction?（）A、DELETEemployees;B、DESCRIBEemployees;C、ROLLBACKTOSAVEPOINTC;D、GRANTSELECTONemployeesTOSCOTHE、ALTERTABLEemployeesSETUNUSEDCOLUMNsal;F、SelectMAX(sal)FROMemployeesWHEREdepartment_id20;14.Why should you back up a duplicated tablespace after a TSPITR is complete？（）  A、 The tablespace cannot be duplicated or restored to any point in time after the duplication. B、 The tablespace cannot be duplicated or restored to the point in time before the duplication. C、 The entire database cannot be restored after a TSPITR， so a backup is required.D、 You cannot bring the tablespace online until its been backed up.E、 There is no requirement to do so， as RMAN will back up the tablespace after the TSPITR.15.Which of the following ALTER DISKGROUP commands does not use V$ASM_OPERATION to record the status of the operation？（）  A、 ADD DIRECTORYB、 DROP DISKC、 RESIZE DISKD、 REBALANCEE、 ADD FAILGROUP16.Given the following RMAN commands，choose the option that reflects the order required to restore your currently operational ARCHIVELOG-mode database.（）   a. restore database  b. recover database  c. shutdown immediate  d. startup  e. restore archivelog all f. alter database open A、 a， b， c， d， e， fB、 c， b， a， d， e， fC、 c， b， a， d， fD、 c， a， b， dE、 c， a， e， b， d， f17.Which two statements about workload capture and replay operations are true？（）  A、 The clients must be created manually on the test machines to perform more realistic testing.B、 Restart the database in RESTRICTED mode before beginning workload replay to enable a clean state for workload replay.C、 Restart the database in RESTRICTED mode before beginning workload capture to enable a clean state for capturing the workload.D、 The application state of the capture system must be identical to the application state of the replay system when the workload replay begins.18.Click the Exhibit button. Which three code fragments， added individually at line 29， produce the output 100？（）A、n = 100；B、i.setX（ 100 ）；C、o.getY（）.setX（ 100 ）；D、i = new Inner（）； i.setX（ 100 ）；E、o.setY（ i ）； i = new Inner（）； i.setX（ 100 ）；F、i = new Inner（）； i.setX（ 100 ）； o.setY（ i ）；19.Given： What is the result？（）A、Compilation fails because of an error in line 3.B、Compilation fails because of an error in line 7.C、Compilation fails because of an error in line 9.D、If you define D e = new E（）， then e.bMethod（） invokes the version of bMethod（） defined in Line 5.E、If you define D e = （D）（new E（））， then e.bMethod（） invokes the version of bMethod（） defined in Line 5.F、If you define D e = （D）（new E（））， then e.bMethod（） invokes the version of bMethod（） defined in Line 9.20.YouperformthefollowingactivitiesduringthedatabaseupgradefromOracleDatabase10gtoOracleDatabase11g: 1.CaptureplansforaSQLworkloadintoaSQLTuningSet(STS)beforeupgrade. 2.LoadtheseplansfromtheSTSintotheSQLplanbaselineimmediatelyaftertheupgrade. Whatisthereasonforperformingtheseactivities?（）A、tominimizeplanregressionduetotheuseofanewoptimizerversionB、tocompletelyavoidtheuseofnewplansgeneratedbyanewoptimizerversionC、topreventplancapturingwhentheSQLstatementisexecutedafterthedatabaseupgradeD、tokeeptheplanintheplanhistorysothatitcanbeusedwhentheolderversionoftheoptimizerisused21.The system was running a normal workload during the last 24 hours. You need to ensure that with the same workload you should be able to flashback tables by three hours. What would you do to find the system recommendations for the undo retention period and the undo tablespace size?（）A、set DB_FLASHBACK_RETENTION_TARGET=10800  B、create a new scheduler window for the time period of 24 hours and use the optimizer statistics C、modify the Automatic Workload Repository (AWR) snapshot time interval to three hours and use ADDMfindings D、specify New Undo Retention as three hours and Analysis Time period as Last One Day in the Undo Advisor page and use its recommendations22.YouneedtoperformcertaindatamanipulationoperationsthroughaviewcalledEMP_DEPT_VU,whichyoupreviouslycreated.Youwanttolookatthedefinitionoftheview(theSELECTstatementonwhichtheviewwascreated.)Howdoyouobtainthedefinitionoftheview?（）A、UsetheDESCRIBEcommandontheEMP_DEPT_VUview.B、UsetheDEFINEVIEWcommandontheEMP_DEPT_VUview.C、UsetheDESCRIBEVIEWcommandontheEMP_DEPT_VUview.D、QuerytheUSER_VIEWSdatadictionaryviewtosearchfortheEMP_DEPT_VUview.E、QuerytheUSER_SOURCEdatadictionaryviewtosearchfortheEMP_DEPT_VUview.F、QuerytheUSER_OBJECTSdatadictionaryviewtosearchfortheEMP_DEPT_VUview.23.TheuserAlicewantstograntallusersqueryprivilegesonherDEPTtable.WhichSQLstatementaccomplishesthis?（）A、GRANTselectONdeptTOALL_USER;B、GRANTselectONdeptTOALL;C、GRANTQUERYONdeptTOALL_USERSD、GRANTselectONdeptTOPUBLIC;24.The ORDERS table belongs to the user OE. OE has granted the SELECT privilege on the ORDERS table to the user HR.Which statement would create a synonym ORD so that HR can execute the following query successfully?（）A、CREATE SYNONYM ord FOR orders; This command is issued by OE B、CREATE PUBLIC SYNONYM ord FOR orders; This command is issued by OE C、CREATE SYNONYM ord FOR oe.orders; This command is issued by the database administrator D、CREATE PUBLIC SYNONYM ord FOR oe.orders; This command is issued by the database administrator 25.Yourmultitenantcontainerdatabase(CDB)containsapluggabledatabase,HR_PDB.ThedefaultpermanenttablespaceinHR_PDBisUSERDATA.Thecontainerdatabase(CDB)isopenandyouconnectRMAN. YouwanttoissuethefollowingRMANcommand: RMAN>BACKUPTABLESPACEhr_pdb:userdata; Whichtaskshouldyouperformbeforeissuingthecommand?（）A、PlacetherootcontainerinARHCHIVELOGmode.B、Taketheuserdatatablespaceoffline.C、Placetherootcontainerinthenomountstage.D、EnsurethatHR_PDBisopen.卷III一.参考题库(共25题)1.Archived redo logs can be copied to more than one destination by Oracle.（）A、 TrueB、 False2.Which of the following describes how a distributed resumable transaction behaves？（）  A、 The resumable setting on the initiating session determines the resumable conditions for the entire distributed transaction.B、 The resumable setting for the initiating instance determines the resumable conditions for the entire distributed transaction.C、 The resumable setting on the initiating session controls only that part of the transaction that occurs within the local instance； remote resumable settings determine the behavior of the distributed parts  of the transaction.D、 None of the above.3.The ORDERS table in the database of a company contains one million records. The table is stored in the DATA tablespace and the index created on the ORDERS table is stored in the index tablespace named INDEXES. On Monday， you failed to start the database because the datafiles of the INDEXES tablespace were missing. You dropped and recreated the INDEXES tablespace by issuing the following command：    SQL>DROP TABLESPACE INDEXES INCLUDING CONTENTS；    SQL> CREATE TABLESPACE INDEXES DATAFILE   ’C:///ORACLE/ORADATA/ORA101t/INDEX01.DBF’ SIZE 50m；   After that， you issued the following command to recreate the index：    CREATE UNIQUE INDEX sales_index_pk ON sales （order_id）   PCTFREE 10   INITRANS 2   MAXTRANS 255   TABLESPACE indexes   STORAGE （   INITIAL 1m  NEXT 1m   PCTINCREASE 0   MINEXTENTS 1   MAXEXTENTS 8192  ）   NOLOGGING   PARALLEL（ degree 4）   Which two clauses are responsible for reducing the time for the recreation of the index？（）A、 PCTFREEB、 MAXTRANSC、 PCTINCREASED、 INITIALE、 NOLOGGINGF、 PARALLEL4.Which two statements are true regarding the WebLogic domain?（）A、A WebLogic domain can have more than one Administration server.B、A WebLogic domain has at least one WebLogic server.C、A WebLogic domain can have at the most one cluster.  D、A WebLogic domain can cross multiple physical machines.  E、Each WebLogic domain is associated with a different Node Manager.5.ClicktheExhibitbuttontoexaminethestructuresoftheEMPLOYEESandTAXtables. Youneedtofindthepercentagetaxapplicableforeachemployee.WhichSQLstatementwouldyouuse?（） A、SELECTemployee_id,salary,tax_percentFROMemployeeseJOINtaxtONe.salaryBETWEENt.min_salaryANDt.max_salary;B、SELECTemployee_id,salary,tax_percentFROMemployeeseJOINtaxtWHEREe.salary>t.min_salaryAND<t.max_salary;C、SELECTemployee_id,salary,tax_percentFROMemployeeseJOINtaxtON(MIN(e.salary)=t.min_salaryANDMAX(e.salary)=t.max_salary);

D、Youcannotfindtheinformationbecausethereisnocommoncolumnbetweenthetwotables.6.You execute the following command in your S production database to change the width of the CUST_NAME column of the CUSTOMERS table：  ALTER TABLE customers   MODIFY （cust_nameVARCHAR2 （40））   /   When you execute the command， it displays the following error message：   ERROR at line 1：   ORA-00054： resource busy and acquire with NOWAIT specified   What could be the reason for the error message？（）A、The database instance is not available.B、The ALTER TABLE command does not have WAIT optionC、The table or a row in the table is currently locked by another user session.D、The database instance is busy processing other user sessions commands.E、The CUSTOMERS table has no long running query active at the time when this request is made.F、The server process executing the ALTER TABLE command is busy with another command execution7.Whichthreefeaturesworktogether,toallowaSQLstatementtohavedifferentcursorsforthesamestatementbasedondifferentselectivityranges?（）A、BindVariablePeekingB、SQLPlanBaselinesC、AdaptiveCursorSharingD、BindvariableusedinaSQLstatementE、LiteralsinaSQLstatement8.TheEMPtablecontainsthesecolumns: LASTNAMEVARCHAR2(25) SALARYNUMBER(6,2) DEPARTMENT_IDNUMBER(6) Youneedtodisplaytheemployeeswhohavenotbeenassignedtoanydepartment. YouwritetheSELECTstatement: SELECTLAST_NAME,SALARY,DEPARTMENT_ID FROMEMP WHEREDEPARMENT_ID=NULL; WhatistrueaboutthisSQLstatement?（）A、TheSQLstatementdisplaysthedesiredresults.B、ThecolumnintheWHEREclauseshouldbechangedtodisplaythedesiredresults.C、TheoperatorintheWHEREclauseshouldbechangedtodisplaythedesiredresults.D、TheWHEREclauseshouldbechangedtouseanouterjointodisplaythedesiredresults.9.selectcount（*）fromstudent和selectcount（id）fromstudent之间的区别是什么？10.ExaminethestructureiftheEMPLOYEESandNEWEMPLOYEEStables: WhichMERGEstatementisvalid?（）A、B、C、D、11.Whichtwocommandsnevertriggeranimplicitrebalancingwithinthediskgroup?（）(Choosetwo.)A、ALTERDISKGROUPmiscMOUNT;B、ALTERDISKGROUPmiscDROPDISKmisc2;C、ALTERDISKGROUPmiscCHECKALLNOREPAIR;D、ALTERDISKGROUPmiscRESIZEALLSIZE1023m;E、ALTERDISKGROUPdgroupAADDDISK'/devices/A*';12.ExaminethestructuresoftheEMPLOYEESandTAXtables. EMPLOYEES EMPLOYEE_IDNUMBERNOTNULL,Primary Key EMP_NAMEVARCHAR2(30) JOB_IDVARCHAR2(20) SALARYNUMBER References MGR_IDNUMBER EMPLOYEE_ID column DEPARTMENT_IDNUMBERForeignkeyto DEPARTMENT_ID columnofthe DEPARTMENTtable TAX MIN_SALARYNUMBER MAX_SALARYNUMBER TAX_PERCENTNUMBER Percentagetaxforgiven salaryrange Youneedtofindthepercentagetaxapplicableforeachemployee.WhichSQLstatementwouldyouuse?（）A、SELECTemployee_id,salary,tax_percentFROMemployeese,taxtWHEREe.salaryBETWEENt.min_salaryANDt.max_salaryB、SELECTemployee_id,salary,tax_percentFROMemployeese,taxtWHEREe.salary>t.min_salary,tax_percentC、SELECTemployee_id,salary,tax_percentFROMemployeese,taxtWHEREMIN(e.salary)=t.min_salaryANDMAX(e.salary)=t.max_salaryD、Youcannotfindtheinformationbecausethereisnocommoncolumnbetweenthetwotables.13.You have many users complaining about slow inserts into a large table. While investigating the reason， you find that the number of indexes on the table is high. You want to find out which indexes are not being used.