Recover Damaged Oracle Dump Files

In this article, various methods for repairing damaged Oracle dump files are explored. Oracle dump files, also known as export files, are used for backup, recovery, and database migration. However, they may become corrupted due to system failures, media storage damage, viruses, or other factors. There are not too much options to try in this case, because Oracle dump format is not publicly documented.

One solution for repairing a corrupted dump file is manual recovery, which involves creating a new database and user account, and then using the IMP or IMPDP commands to export the data from the damaged dump file:

IMP username/password@database FROMUSER=dump_file_user TOUSER=new_db_user IGNORE=y FILE=path_to_dump_file.dmp
IMPDP username/password@database REMAP_SCHEMA=source_schema:target_schema TABLE_EXISTS_ACTION=REPLACE DUMPFILE=dump_file_name.dmp

Similar approach can also be implemented through Oracle SQL developer studio via the following steps.

  • upload the dump file into some folder on the Oracle database server
  • create new schema and grant the sufficient privileges to the user (CONNECT, RESOURCE, DBA, UNLIMITED TABLESPACE)
  • create data pump directory and grant the sufficient privileges to the user created above for that directory
  • Create a new connection as DBA
  • Expand the connection, highlight ‘Data Pump’ entry and select ‘Data Pump Import Wizard’ menu item
  • Select the data pump directory created on the previous step and give the data dump name as the “File names or URI” column
  • Click on “add row” in the Re-Map Schemas section of the wizard, select the appropriate schema in the database dump as the source and specify the destination as newly created schema
  • Select created data pump folder to save the log file

Those methods are straight forward and quite easy to implement. It can work for slightly corrupted dump files where damage does not affect important data. However, it may result in incomplete database recovery or abnormal termination for more severe damage.

Another option is to use the data recovery service offered by Intelligent Converters, a company that has researched the format of Oracle export files and developed conversion tools for them. Their specialists can recover all available data from highly damaged files using their expertise in low-level data recovery. The result of successful recovery can be either valid Oracle dump or script file containing statements to create all database entries and import the data. Price of the recovery service depends on the volume and complexity of the dump file.

You can learn more about Oracle dump file recovery service provided by Intelligent Converters and request a quote at: