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Oracle 10g Availability Enhancements, Part 1: Backup and Recovery mprovementsBy !im "#uprynski$ynopsis% Oracle 10g offers significant enhancements that help insure the high availability of any Oracle database, especially in the arena of disaster recovery. This article - the first ina series - concentrates on several new features available for backup, restoration, and recovery of Oracle databases, especially when using Oracle Recovery anager !R"#$.If you have read my earlier article about setting up disaster recovery for Oracle databases, you already know that I sincerely enjoy experimenting with the myriad robust features of Oracle Recovery Manager (RM!"# I am willing to bet that any seasoned Oracle $% sighs knowingly and thankfully when she thinks of a potentially disastrous loss of data that has been averted by a well&planned backup and recovery strategy that incorporates RM!#Oracle '(g expands significantly the RM! backup, restoration, and recovery features that Ihave grown to appreciate# &lash Backup and Recovery appears to be the most exciting improvement, and I will cover that in greater detail in the next article in this series, but for now, this article will focus on numerous significant features that beg for illustration#Backup EnhancementsE'panded mage "opying &eatures%standard RM! backup set contains one or more backup pieces, and each of these pieces consists of the data blocks for a particular datafile stored in a special compressed format# )hen a datafile needs to be restored, therefore, the entire datafile essentially needs to be recreated from the blocks present in the backup piece#n image copy of a datafile, on the other hand, is much faster to restore because the physical structure of the datafile already exists# Oracle '(g now permits image copies to be created at the database, tablespace, or datafile level through the new RM! directive BA"()P A$ "OP*# *or example, here is a command script to create image copies for all datafiles in the entire database+R,! -. /et the default channel configuration# !ote the use of the . 0, directive to insure uni1ue file names for the image copies22O345 36!!52 dbkp' $57I35 4895 $I/: *ORM4 ;c+R5A6/$.A.)$ lists the historical status of all RM! jobs# 6ere is the resulting output from my (not always successfulI" experiments with image backups+ Results of most recent Recovery Manager sessions 3ommandR4ime/tamp/essionction /tatus&&&&&&&&&&&&&&&&&&&& &&&&&&&& &&&&&&&& &&&&&&&&&&&&&&&&&&&&&&&&H((N&''&H(4''+N(+GG3OMM!$%3:,9 3OM92545$H((N&''&H(4''+N(+GG/5//IO!RM! 3OM92545$H((N&''&H(4''+GE+F(/5//IO!RM! 3OM92545$ )I46 5RROR/H((N&''&H(4''+GE+F(3OMM!$%3:,9 *I25$H((N&''&H(4''+GG+NE3OMM!$%3:,9 *I25$H((N&''&H(4''+GG+NE/5//IO!RM! 3OM92545$ )I46 5RROR/M rows selected#/ee +isting 1%? for the 1ueries used to create this output#mproved Recovery "atalog 5aintenance% Oracle '(g offers a new catalog maintenancecommand, )6RE7$.ER -A.ABA$E, to remove all information about an Oracle database from an RM! repository# -ropping a -atabase "ompletely% If you really must drop an entire database, the new -ROP -A.ABA$E command will remove all of the specified database;s physical files, including control files, datafiles, online redo log members, and server parameter files (if any exist"# !ote that the database must be mounted in exclusive, restricted mode for this command to succeed#"onclusionOracle '(g;s new Recovery Manager features greatly expand the flexibility and reliability of any Oracle $%;s tool kit for disaster recovery planning, backup strategies and failure recovery scenarios# nd I;ve just scratched the surfaceI s promised, the next article in this series will focus on one of the most intriguing new availability features+ Flash Backup and Recovery.Re2erences and Additional Reading)hile there is no substitute for direct experience, reading the manual is not a bad idea, either# I have drawn upon the following Oracle '(g documentation for the deeper technical details of this article+B10@4:A01 Oracle Database Backup and Recovery Advanced User's GuideB10@4?A01 Oracle Database Backup and Recovery BasicsB10@?0A01 Oracle Database New Features GuideB10@@0A01 Oracle Database Recovery ana!er Re"erence/*|| Oracle 10g RMAN Listing 1|||| Contains examples of new Oracle 10g Recovery Manager RMAN! feat"res#|||| A"t$or% &im C'"pryns(i|||| )sage Notes%|| *$is script is provi+e+ to +emonstrate vario"s feat"res of Oracle 10g,s || new Recovery Manager RMAN! feat"res an+ s$o"l+ -e caref"lly proofrea+|| -efore exec"ting it against any existing Oracle +ata-ase to ins"re|| t$at no potential +amage can occ"r#||*/ ....... Listing 1#1% /mage Copy 0n$ancements .....R)N 12 3et t$e +efa"lt c$annel config"rationALLOCA*0 C4ANN0L +-(p1 506/C0 *780 5/39 :ORMA* ,c%;oracle;rman-("p;ic2 3$ow w$at files will -e "se+ to restore t$e 373*0M ta-lespace,s +atafileR03*OR0 5A*A:/L0 1 8R06/0H>2 3$ow w$at files will -e "se+ to restore a specific ta-lespaceR03*OR0 *A?L038AC0 $r 8R06/0H>2 3$ow a s"mmary for a f"ll +ata-ase restoreR03*OR0 5A*A?A30 8R06/0H 3)MMAR7>2 Close t$e log file38OOL LOK O::>....... *$e res"lting o"tp"t%.....3pooling starte+ in log file% c%;oracle;rmancm+;restores"mmary#lstRecovery Manager% Release 10#1#0#@#0 . 8ro+"ctionRMANQ 3tarting restore at @1.NO6.0O"sing c$annel ORA


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