Tuesday, June 28, 2016

Export Oracle Database


In the name of Allah, Most Gracious, Most Merciful
Praise be to Allah, blessing and peace be upon our prophet Mohammed, his family and his companions. After that,


Well, it's quite important to realize how you keep up your existing data safe
Taking a backup file from your database user is the key to safe guard your data.

Task Definition:   

Export data from Oracle database

       What Is the Export Utility?

        The Export utility provides a simple way for you to transfer data objects between Oracle  databases,  even if they reside on platforms with different hardware and software configurations.The extracted data is written to an Export file.


        Before using Export :            

  • Ensure there is sufficient disk or tape storage to write the export file
  • Verify that you have the required access privileges. 

  
Task Solution:

There are two Export utility methods:

1.  Exp.      
2.   Expdp. 

       Both methods will generate a dump file with extension file_name .dmp
    The  Export dump file is an Oracle binary-format dump file. The dump file name and  path directory is pre-determined before running the export utility.

      Start Exporting Data:

     Select Start menu> Run> write CMD then a window will open write the following command according to your naming requirements:


                              exp /@ file=.dmp log=.log full=y;

exp  user_name/password@database_instance  file= file_name.dmp
 log=log_file_name.log   full=y;

Example:

Exp Scott/tiger@orcl file=test.dmp  log= test_log.log full=y;


·                      It is  recommended to start exporting data with expdp command as follow:

    Expdp user_name/password@database_instance  file= file_name.dmp
 log=log_file_name.log   full=y;

            Example:


Expdb Scott/tiger@orcl file=test.dmp  log= test_log.log full=y;

The Data Pump Export utility is invoked using the expdp command. The characteristics of the export operation are determined by the export parameters you specify. These parameters can be specified either on the command line or in a parameter  file. 


Expdp Vs. Exp


  • Both does the same functionality; Exporting data.
  •   The original Export utility dates back to the earliest releases of Oracle, and it's quite slow and primitive compared to Data Pump that  gives 15 – 50%  performance improvement than exp/imp.


Note:


The contents of an export file can be displayed without actually performing an import.  How ???  using the Import   SHOW   parameter.

 The SHOW parameter Default: 'N' can be used ONLY with the FULL=Y 

When SHOW=y, the contents of the export file are listed to the display and not imported. 
The SQL statements contained in the export are displayed in the order in which Import will execute them.

Learn more about:

 ·        Import Oracle Database


Hope this helps...

My success only comes from Allah, pls. note your comments and suggestions are great help for me in progress thanks in advance.