HOW TO: Recover a deleted object from a PowerCenter versioned repository

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Solution :

If the PowerCenter repository is a versioned repository, it is possible to rollback changes to previous (checked-in) versions.
User gets an object (such as Mapping, Workflow or Transformation) deleted then it is no longer available through the GUI 
but all versions are still in the repository.

To recover the last version if you deleted an object you can first check if the object is still checked out:
  1. Select in the PowerCenter Client menu Versioning > Find Checkouts...
  2. Locate the deleted object, verify if it is the deleted object and restore the object through right-click > Undo Checkout
If the deleted object was already checked-in, you can recover the object by using the Repository Managers Query tool:
  1. Open in the Repository Manager's menu Tools > Queries...
  2. Create a new query at least with the filter parameter 'Version Status' 'Is Equal To' 'Deleted'
  3. You can define the query more specific if needed or use an existing one.
  4. Run the query.
  5. Locate the deleted object, example, by sorting for Time Stamp.
  6. Right-click on the object and select View History
  7. In the resulting list you should see all versions of the object. The latest one is the deleted version.
  8. Select the latest deleted version.
  9. In the menu select Tools > Purge Object Version
  10. When you then select Ok from the following dialog the version gets removed from the repository
    and the version before is active again.