To recover from a dropped
or truncated table, a dummy database (copy of primary) will be restored and
recovered to point in time so the table can be exported. Once the table
export is complete, the table can be imported into the primary database.
This dummy database can be a subset of the primary database. However, the
'dummy' database must include the SYSTEM, UNDO (or ROLLBACK), and the
tablespace(s) where the dropped/truncated table resid...
Showing posts with label Recovery. Show all posts
Showing posts with label Recovery. Show all posts
Monday, 15 September 2014
Standby MRP needs old log sequence even after restore of incremental backup at standby
At standby
applied incremental backup but MRP process at standby is looking
for very old sequence.
SQL>SELECT
ARCH.THREAD# "Thread", ARCH.SEQUENCE# "Last Sequence
Received", APPL.SEQUENCE# "Last Sequence Applied",
(ARCH.SEQUENCE# - APPL.SEQUENCE#) "Difference"
FROM (SELECT THREAD# ,SEQUENCE#
FROM V$ARCHIVED_LOG&nb...
Saturday, 10 May 2014
LOG MINING IN ORACLE DATABASE
Suppose data in a table has been deleted.
Audit trail was not enabled, therefore we do not have a clue of the user who has
performed deletion and there are around 30 users that have DELETE rights on
that table. Management want to know the name of the user, here we can use Oracle LOG MINING feature to filter out
the transactions performed during that period.
Note: Make sure the Archive log must be
enabled previously, if you want to use LOG Mining technique.
CONSIDERATIONS
Database : ORCL
Schema : SCOTT Table : STUDENTS
Date of Deletion...
Monday, 23 December 2013
Restoring an RMAN Backup to Another Node /Clone Database
In certain circumstances, it may be desirable to restore a
database from an RMAN backup onto a machine other than the original
host.
For example,Restore and recover data at a given point in time for UAT/Testing, or to
duplicate a production instance.
The example assumes:
the target database is on host A
the database is to be restored onto host B
the directory structure of host B is different to host A
the ORACLE_SID will not change for the restored database
a recovery catalog is being used
the backups were carried out to disk (for...
Thursday, 19 December 2013
Full Database Recovery or Disaster Recovery.
You use the RESTORE and RECOVER commands to restore and recover the database.RMAN checks last good backup set and restore the datafiles to the state they were in when that backup set was created. When restoring database files with RMAN, it reads the datafile header and makes the determination as to whether the file needs to be restored.
If you cannot restore datafiles to their default locations, then you must update the control file to reflect the new locations of the datafiles. Use the RMAN SET NEWNAME command within a RUN command to specify...