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Incomplete Recovery (until log sequence)

Point in time recovery using RMAN (until a log sequence number) Recovery Objective SQL> conn scott/tiger Connected. SQL> select count(*) from myobjects; COUNT(*) ———- 249410 Switch a logfile SQL> conn / as sysdba Connected. SQL> alter system switch logfile; System altered. Note the current log sequence number (13) SQL> archive log list Database log mode … continue reading

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Incomplete Recovery (until point in time)

POINT IN TIME RECOVERY via RMAN Scenario: DBA dropped the tablespace TEST which is important for application. Requirement: We need to restore the database before the TEST tablespace was dropped. Solution: SQL> drop tablespace test including contents and datafiles; Tablespace dropped. DBA realized the mistake; He will refer alert log for the exact timing when … continue reading

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Loss Of All Files – Disaster Recovery

RECOVERY SCENARIO: Complete loss of all database files including SPFILE using RMAN Database Details —————— Database Name=OPSDBA Machine Name=ITLINUXDEVBLADE07 DBID=1499754868 (select dbid from v$database) SIMULATING CRASH ———————— opsdba:/u01/ORACLE/opsdba>ls -l total 1948980 drwxr-x— 2 oracle dba 4096 Feb 12 13:35 arch -rw-r—– 1 oracle dba 7389184 Feb 12 13:57 control01.ctl -rw-r—– 1 oracle dba 7389184 Feb … continue reading

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RMAN Restore on another machine with different file system- same database name

RMAN Restore on another machine with different file system – same database name Primary/Target Machine ITLINUXDEVBLADE08 Secondary/Auxiliary Machine ITLINUXDEVBLADE07 Database Name OPSDBA Note For this example, we will be using TSM in order to backup and duplicate the database to the new machine. Hence TSM needs to be configured on both the machines. If you … continue reading

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NOARCHIVELOG Database Recovery

NOARCHIVELOG DATABASE RECOVERY VIA RMAN Your database is running in No Archive log mode and you have daily/weekly RMAN backup configured. One fine day, your server crashed and you lose one of the disks or all the disks. You have no other option but to restore the whole database backup to point of last valid … continue reading

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Recovery of a dropped tablespace

Recovery of a dropped tablespace To recover from a case of a dropped tablespace, the Tablespace Point In Time Recovery (TSPITR) method cannot be used. When you drop a tablespace, the controlfile will then no longer have any records of the tablespace which has been dropped. Attempts to use the RMAN RECOVER TABLESPACE command will … continue reading

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Oracle Real time Interview Questions with Answer

1) How can you see the Current SCN number of the database? > Select current_scn from v$database; 2) How can you see the Current log sequence number the logwriter is writing in to? > Select * from v$log; 3) If you are given a database, how will you know how many datafiles each tablespace contain? … continue reading

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Daily Activities of Oracle Database Administrator

Daily Work of DBA: Check the Database Availability Check the Listener Availability Monitoring space Availability Viewing the Alert log file to analyze the ORA errors if any. Check tablespaces should not be used more that 95%. Viewing the temporary files, through the DBA_TEMP_FILES. Daily resolving the tickets by using Remedy ticketing tool. Taking backups by … continue reading

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The flashback recovery area has run out of space …under different scenarios

The flashback recovery area has run out of space what different solution to overcome that issue. as we see some expert solution to this question lets add some scenarios on that,now i know how i increase-up the FRA say db_recovery_file_dest_size = 10G what happened when we reduced it to db_recovery_file_dest_size = 5G……? The flash recovery … continue reading

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What is the difference between ‘archived’ and ‘applied’ on v$archived_log view ?

Archived means whether the archive is generated or not on primary and  applied means whether the archive applied on standby or not. Enjoy.  

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