吉林大学大型数据库设计与实现dba-06.ppt

MaintainingtheControlFile

ObjectivesAftercompletingthislesson,youshouldbeabletodothefollowing:ExplaintheusesofthecontrolfileListthecontentsofthecontrolfileMultiplexandmanagethecontrolfileManagethecontrolfilewithOracleManagedFilesObtaincontrolfileinformation

ControlFileThecontrolfileisabinaryfilethatdefinesthecurrentstateofthephysicaldatabase.LossofthecontrolfilerequiresrecoveryIsreadatMOUNTstageIsrequiredtooperateIslinkedtoasingledatabaseShouldbemultiplexedMaintainsintegrityofdatabaseSizedinitiallybyCREATEDATABASEControlfilesDatabase

ControlFileContentsAcontrolfilecontainsthefollowingentries:DatabasenameandidentifierTimestampofdatabasecreationTablespacenamesNamesandlocationsofdatafilesandredologfilesCurrentredologfilesequencenumberCheckpointinformationBeginandendofundosegmentsRedologarchiveinformationBackupinformation

MultiplexingtheControlFile

UsingSPFILEAltertheSPFILEShutdownnormal:CreateadditionalcontrolfilesStartthedatabase:SQLALTERSYSTEMSETcontrolfiles=$HOME/ORADATA/u01/ctrl01.ctl,$HOME/ORADATA/u02/ctrl02.ctlSCOPE=SPFILE;$cp$HOME/ORADATA/u01/ctrl01.ctl $HOME/ORADATA/u02/ctrl02.ctlSQLstartupSQLstartup

MultiplexingtheControlFile

Usinginit.oraShutdownthedatabaseinanormalstate:Copytheexistingcontrolfiletoanewnameandlocation:Addthenewcontrolfilenametoinit.ora:Startthedatabase:SQLshutdownnormalCONTROL_FILES=(/DISK1/control01.ctl,/DISK3/control02.ctl)$cpcontrol01.ctl.../DISK3/control02.ctlSQLstartup

ManagingControlFileswithOMFControlfilesareOMFcreatediftheCONTROL_FILESparameterisnotspecified.OMFcontrolfilesarelocatedatDB_CREATE_ONLINE_LOG_DEST_N.ControlfilenamesareuniquelygeneratedanddisplayedinthealertSID.logfilewhenthefilesarecreated.

ObtainingContro