Oracle 11g RMAN Active Database Duplication Feature.

Earlier in pre Oracle 11g releases in order to clone or duplicate a database, we had to take backups with RMAN of the source database and copy the backup files to the destination server as well. But with 11g database duplication or cloning has gone one step further. With the new RMAN active database duplication feature taking backups and staging them is no longer required. RMAN can now directly clone the database from the source without the need for backups. The only criteria are that the source database should be in archivelog mode.

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Oracle 11g I/O Calibration Feature.

Earlier in order to assess the I/O capabilities of the system
on which you would install Oracle database, there were
two options.

1)Use third party tools (Mercury loadRunner, Benchmark Factory etc).
2)Use ORION from Oracle.

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Oracle 11gR2 Deinstall tool.

Before 11gR2 Uninstalling the Oracle software was really
a pain both on windows as well as on linux platforms.

But now Oracle 11gR2 with comes with aa awesome tool 'Oracle Deinstall utiliy'.

Just execute one simple command answer a couple of questions
and you can remove your whole Oracle software along with your database
and listeners.

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Oracle 11g create spfile from memory.

In pre Oracle 11g releases we had the feature of conversion from SPFILE to PFILE and vice versa. But Oracle 11g has gone one step further, SPFILE can now be created directly from memory.

SQL> create spfile=’/u01/app/spfileorcl.bak’ from memory;

This command will capture all the settings from the memory and dump them to an SPFILE. This is a very useful utility to take backup of your SPFILE before any changes are made using ‘alter system’ command. In order to check and read the new created file the following command can be used : -

 
SQL>!strings /u01/app/spfileorcl.bak

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Oracle 11g Memory Advisor feature.

Among many dynamic views oracle has added a new view,
V$MEMORY_TARGET_ADVICE. The purpose of this view is 
to give recommendations related to the 
sizing of the memory_target parameter.

Before going further please make sure that memory
management is set to automatic in your database,
otherwise this feature will not work.

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SQL*LOADER

This example illustrates how to insert data from a text file to a table in the HR schema using SQL loader.

The data file is named as “records.dat”.
The controlfile file is named as “records.ctl”.
The logfile is named as “records.log”.

1)Connect to the HR schema and create a tables as “TEST”.

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How to repair broken MBR in RHEL 6 ?

1) Go to the grub command line when the system boots up.
2) Find the partition which contains the grub.conf file.

grub> root
  (hd0,0): Filesystem type is unknown, partition type 0x8e

3) Reinstall grub on the returned partition.

grub> setup (hd0)

4) The above command should fix your broken MBR, now reboot the system.

grub> reboot

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