Will this process affect the availability of the database?

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http://rockingtechnology.blogspot.co.uk/2011/06/oracle-backup-and-restore-code-in-cnet.html

As per the proposed code in the above article, more specifically:

ProcessStartInfo psi = new ProcessStartInfo();
psi.FileName = "C:/oracle/product/10.2.0/db_1/BIN/exp.exe";
Process process = Process.Start(psi);
process.WaitForExit();
process.Close();

How can I expect the database to be affected with regards to interruption of CRUD operations from elsewhere once calling Process.Start(psi) and, hence, executing exp.exe?

Using Oracle's exp.exe process - will the sessions of all users currently writing to the db in question be killed, for example? I'd imagine (or at least hope) not, but I haven't been able to find documentation to confirm this.


EXP and IMP are not proper backup and recover tools. They are intended for exchanging data and data structures between Oracle databases. This is also true for their replacement, Data Pump (EXPDP and IMPDP).

Export unloads to a file so it won't affect any users on the system. However if you want a consistent set of data you need to use the CONSISTENT=Y parameter if there are any other users connecting to the system .

Interestingly Data Pump does not have a CONSISTENT parameter. It unloads tables (or table partitions) as single transactions but the only way to guarantee consistency across all database objects is to use the FLASHBACK_SCN parameter (or kick all your users off the system).


"It is all in aid of DR."

As a DR solution this will work, with the following provisos.

  1. The users will lose all data since the last export (obvious)
  2. You will need to ensure the export is consistent across all objects
  3. Imports take time. A lot of time if you have many tables or a lot of data. Plus indexes, etc

Also remember to export the statistics as well as the data.