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

单项选择题You work as a database administrator for Supportcenter.cn. Users in the Supportcenter.cn 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 return
B.Create more undo segments
C.Create another undotablespace
D.Increase the size of the undo tablespace

单项选择题InyourSupportcenter.cndatabaseservertheparameterPLSQL_CODE_TYPEhasbeensettoNATIVE.Whichobjectwouldbeachievedbythesetting？（）

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.

单项选择题YouworkasadatabaseadministratorforSupportcenter.cn.OnaMondaymorning，youfindthedatabaseinstanceaborted.Afterinspectingthealertlogfile，youexecutetheSTARTUPcommandinSQL*Plustobringtheinstanceup.Whatstatementistrue？（）

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.

单项选择题InyourSupportcenter.cnproductiondatabase，youfindthatthedatabaseusersareabletocreateandreadfileswithunstructureddata，availableinanylocationonthehostmachinefromanapplication.Youwanttorestrictthedatabaseuserstoaccessfilesinaspecificlocationonthehostmachine.Whatcoulddotoachievethis？（）

A.Modify the value for the UTL_FILE_DIR parameter in the parameter file
B.Grant read and write privilege on the operating system path to the database users
C.Modify the value for the LDAP_DIRECTORY_ACCESS parameter in the parameter file
D.Modify the value for the PLSQL_NATIVE_LIBRARY_DIR parameter in the parameter file
E.Create a directory object referring to the operating system path， and grant read and write privilege on the directory object to the database users

单项选择题YouworkasadatabaseadministratorforSupportcenter.cn.Yourdatabaseisconfiguredforautomaticundomanagement.UNDO_RETENTIONissetto3hours.Youwanttoflashbackatablethatwascreatedlastyear.Howfarbackcantheflashbackquerygo？（）

A.3 hours
B.6 months
C.until last year
D.until last commit
E.until the point when the undotablespacewas refreshed
F.until the database is shut down and the memory erased