| Question |
| Explain, what backup can perform in ORACLE? |
| Answer |
| FO ORACLE, YOU CAN HAVE TWO KINDS OF BACKUP — LOGICAL BACKU PAND PHYSICAL.. |
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| Question |
| Explains different types of backup in oracle ? |
| Answer |
| FOR ORACLE, YOU CAN HAVE TWO KINDS OF BACKUP — LOGICAL BACKUP AND PHYSICAL.. LOGICAL BEING THE IMPORT / EXPORT AND PHYSICAL BEING THE RMAN BACKUP… |
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| Question |
| What methods we can use for taking oracle backup? |
| Answer |
| FOR ORACLE, YOU CAN HAVE TWO KINDS OF BACKUP — LOGICAL BACKUP AND PHYSICAL.. LOGICAL BEING THE IMPORT / EXPORT AND PHYSICAL BEING THE RMAN BACKUP… |
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| Question |
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| Is backup types same in all Oeacle editions (standard, Enterprise,etc..)? |
| Answer |
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| YES ..IT IS THORUGH RMAN UTILITY WHICH COMES COMES WITH ALL EDITIONS OF ORACLE… |
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| Question |
| If we don’t have any third party backup software tool, then can i backup my data into tape? If yes, then how? |
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| Answer |
| NO IT ISNT POSSIBLE …. AS YOU HAVE TO INTEGRATE YOU ORACLE WITH MML TO BACKUP UR DATA ON TAPE…. |
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| Question |
| Could you pls tell us when to use back up and recovery and how does it works. Being a PL/SQl developer want to know this activity. |
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| Answer |
| HI, SEE IDEALLY YOUR BACKUP IS DEFINED BASED ON HOW CRITICAL YOUR DATA IS.. HOW FREQUENT YOU SHOULD TAKE BACKUP DEPENDS ON THAT..ONCE A WEEK FULL BACKUP IS ALWAYS RECOMMENDED. RECOVERY COMES INTO PICTURE WHEN THERE IS SOME DISASTER.. |
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| Question |
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| Which backup is more preferable to do in oracle ? |
| Answer |
| RECOMMENDED IS RMAN BACKUP.. |
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| Question |
| Suppose you have schema having 2500 objects. your requirement is to create separate copy of same schema with objects,procedures, grants etc. but without data. also want newly created table structure should not occupy space as in earlier schema. |
| Answer |
| YOU CAN TAKE SCHEMA LEVEL BACKUP USING IMPDP AND EXCLUDE DATA…AND ALSO USE REMAP SCHEMA FOR NEW NAME OF SCHEMA. |
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| Question |
| Explain the process of backup ? |
| Answer |
| TWO TYPES OF BACKUP POSSIBLE..SO LOGICAL HAS DIFFERENT PROCESS AND PHYSICAL HAS DIFFERENT.. |
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| Question |
| If we simply run this: RMAN> copy datafile ‘H:dbfstest.DBF’ to ‘+DG/dbname/test.dbf’ to copy my datafile from physical location to ASM. Can i do this for temporary tablespaces? |
| Answer |
| YOU CANNOT MOVE TEMP..BUT AN HAVE A NEW ONE CREATED.. |
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| Question |
| Can we take backup of single table or schema?, If yes, then how? |
| Answer |
| YES..USING LOGICAL BACKUP. |
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| Question |
| You have mentioned two types of backup we can take.. logical & physical.. logical I have understood, but what is physical.. please explain? |
| Answer |
| IT IS THE BACKUP OF YOUR PHYSICAL FILES USNG RMAN UTILITY.. |
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| Question |
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| What is the diff b/w RMAN incremental/differential backup |
| Answer |
| FOR RMAN INCREMENTAL— IT IS THE CHANGED DATA SCHEDULED FOR BACKUP. DIFFERENTIAL IS BACKUP OF ALL THE CHANGED DATA SINCE THE LAST SUCCESSFUL FULL BACKUP. |
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| Question |
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| What is a Logical Backup and how would it be performed ? |
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| Answer |
| LOGICAL BACKUP IS THE BACKUP OF YOUR DATABASE OBJECTS..IMPDP/EXPDP , IT WOULD BE PERFORMED ONLINE RUNNING JOBS AT THE BACKUPEND. |
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| Question |
| Tell me any new features in 11g for RMAN? |
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| Answer |
| RMAN Proactive health checks,DATABASE ADVISOR, Faster Backup Compression,Duplicate Database from Backup (11gR2 only), Set NEWNAME Flexibility while restoring Database (11gR2 only) |
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| Question |
| Consider scenario where I don’t have backup of my control file and i want to recover database with incosistent recovery using current control file ,what will be the scn at my control file.after recovery ? |
| Answer |
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| SCN WOULD BE SAME…AS U USING SAME CONTROLFILE.. |
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| Question |
| Why more redo logs are generated when the database is in begin backup mode? |
| Answer |
| In the begin backup state, Instead of writing the changes that have been done in the block, The entire block is written to the redo log files. |
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| Question |
| Why more redo logs are generated when the database is in begin backup mode? |
| Answer |
| In the begin backup state, Instead of writing the changes that have been done in the block,The entire block is written to the redo log files. |
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| Question |
| I have heared there some different types of backup- Full, differential, log, archive, cold, etc…are these backups are different or same? if different the please explain what is the difference? |
| Answer |
| DIFFERENT TYPE OF BACKUP IF U SAY IN ORACLE , THEN ONLY TWO LOGICAL AND PHYSICAL BACKUP. DIFFERNETIAL ,NCREMENTAL ARE DIFFERENT WAYS OF BACKUP. |
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| Question |
| I want to restore one table from rman backup. Is there any option to restore single table from rman backup or otherwise full datbabse only we have to restore |
| Answer |
| YES..WE CAN TAKE SINGLE TABLE BACKUP.. |
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| Question |
| My database have 10 online redolog files. all are deleted by someone but i have only day before yesterday’s backup. How can i recover this deleted redo log file upto this time? |
| Answer |
| IF YOU REDO LOG FILES ARE NOT IN USE ..U CAN CREATE NEW LOGFILES.. AND DATA CONSSITENTCY WOULD BE MAINTAINED AS ARCHVIES U MITE HAVE.. |
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| Question |
| How can we recover a database in last incarnation, because the archived logs of current incarnation could not be applied for recovery .. Thanks Rahul |
| Answer |
| YOU RESTORE YOUR OLD FULL RMAN BACKUP USING UNTIL CANCEL RECOVERY. |
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| Question |
| As confirmed by you, there are different ways of backup. Request to list the same and explain difference between them. |
| Answer |
| DIFFERENTIAL — CHANGES BACKED UP SINCE YOUR LAST FULL BACKUP.. INCREMENTAL—LATEST CHANGES.. |
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| Question |
| At one time you lost parameter file accidentally and you don’t have any backup. How you will recreate a new parameter file with the parameters set to previous values.? |
| Answer |
| OK..YOU CAN FIND IT IN ALERT LOG FILE AND AWR REPORT IF IT IS ENABLED. |
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| Question |
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| An application user accidently deleted 1000 rows in emp table two hours before. Is it possible to recover those deleted rows using RMAN? |
| Answer |
| RECYCLE BIN IS ONE OPTON….. |
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| Question |
| I don’t use flashback feature that is disabled becuase that needs be allocated some extra space. Is it possible using any alternative method? |
| Answer |
| RECYLCE BIN |
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| Question |
| Tell me how can i improve RMAN backup performance? |
| Answer |
| THIS WOULD BE A SEPARATE CHAT …STILL U CAN IMPROVE PERFORMNCE USING PARELLISM.. |
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| Question |
| Is recovery possible of single schema? |
| Answer |
| YES |
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| Question |
| I want to create a UAT setup having DB same as of production, which backup I should take and restore on UAT? |
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| Answer |
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| DUPLICATE FEATURE IN 11G.. |
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| Question |
| Is there any feature in oracle, we can scheduled automatic backup? |
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| Answer |
| You CAN HAVE CRON JOBS OR BAT FILES FOR AUTOMATIC BAKCUP.. |
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| Question |
| How many types are physical backup? Only RMAN or some other backup also there? |
| Answer |
| HOT BAKCKUP AND COLD BAKCUP…. |
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| Question |
| What are the benefits of using RMAN backup over hot backup? |
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| Answer |
| REDOS ARE GENERATED LESS…MANAGEBILITY IS WITH RMAN… |
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| Question |
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| What purpose the physical & logical back serve |
| Answer |
| DEPENDS ON YOUR ENVIROMENT… AND NEED.. |
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| Question |
| In a table one row is corrupt. how to recovery that particular row? |
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| Answer |
| RECYLCE BIN. |
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| Question |
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| Can you explain the difference between cumulative backup and differential backup? |
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| Answer |
| Differential backup (for level 1 parents only): The default is differential backup, where RMAN looks for last level 1 or level 0 backup, and a differential backup only captures those data block changes that were made after those backups. Differential backups are faster because there are fewer changes stored, but they take longer at recovery time. · Cumulative backup (for level 0 or level 1 parents): With a cumulative backup, RMAN backups up all data block changes that are made after a level 0 backup. The main advantage of cumulative backup over differential is the fast recovery time, but at the expense of a longer daily backup window and more disk usage. |
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| Question |
| Could you tell me what is recycle bin? |
| Answer |
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| THAT IS A FEATURE IN ORACLE…. |
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| Question |
| What is recovery? What are its types? Do we have to follow some procedure or defined/standard steps to do recovery of a DB? |
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| Answer |
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| RECOVERY IS GETTING UR ENVIRMNT BACK TO THE SAME STATE..YES U DO HAVE STRATEGIZE.. |
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| Question |
| I took export of one table without data. size of table was 5GB. now importing same in different schema but blank table is occupying 5GB of space. why this is happening and how can I overcome this situation. |
| Answer |
| WITHOUT DATA THEN HOW SIZE IS 5GB ?? PLEASE EXPLAIN.. |
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| Question |
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| What is cold backup.. plz explain? |
| Answer |
| IT IS CONSISTENT BACKUP TAKEN WHEN DB IS DOWN…IT TAKES BAKCUP OF ALL PHYSICAL DB FILES. |
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| Question |
| Could you explain what is the command for using recycle bin? |
| Answer |
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| ON SQLPLUS U CAN CHECK GIVING COMMND AS SHOW PARAMETER RECYLCE TO CHECK WHETHER THAT FEATURE IS ON OR NOT…. |
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| Question |
| I have taken a expdp backup that size is 300GB from proddb and i want to import into testdb but i don’t have enough space in OS level in testdb to occupy the dumpfile. how can i import this dumpfile into testdb? |
| Answer |
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| NETWORK SHARE ?? |
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| Question |
| Is there any way to check last DB full bkp and incremental bkp? |
| Answer |
| YES….IN RMAN LIST BACKUPSET… |
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| Question |
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| If recycle bin parameter on in the database then how to recover single row in a table? please provide the command? |
| Answer |
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| COMMND IS LENGTH…FIRST YOU WILL HAVE YOU DO LITTLE ANALYSIS AS TO WHERE YOUR ORIGINAL TABLE RESIDES ON RECYCLE BIN ..BECZ IT STORES THE DATA IN BINARY FORMAT.. |
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| Question |
| While performing export storage clause is also part of create table statement within import file. now if we are performing import same storage clause comes in effect and space is allocated to table while import as it was there in older schema ir-respective of data. |
| Answer |
| NOT SURE ABOUT THIS STORAGE CLAUSE.. |
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| Question |
| And for logical backup.. hw we can check last backup |
| Answer |
| YOU CAN GIVE DATE FORMAT AT THE END OF DUMPFILE AND IDENTIFY IT LATER ..AS IT IS MANAGED BY USER.. |
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| Question |
| Row level recovery is possible in expdp/impdp? if yes what is the command |
| Answer |
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| impdp scott/tiger dumpfile=dmp1.dmp schemas=SCOTT query=EMP where salary > 1500000 directory=dpmp logfile=log_123.log |
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| Question |
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| Let me clear for recover a table or rows using Recycle bin. database should be enabled flashback feature. Am i right? |
| Answer |
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| NO..IT IS DIFFERENT ORACLE FEATURE. |
