As a result it reduces lots of junk that is taken up in the database.
Besides deleting a large amount of redundant post revisions, it helps to increase the speed of implementation of the SQL statement and so is your WordPress speed.
Install And Setup Delete-Revision Plugin
Go to: http://wordpress.org/plugins/delete-revision/
1. Install it.
2. Click on Activate Plugin.
3. Go to Tools and look for Delete-Revision.
4. Click on it and it will immediately show you the data.
5. That's all you have to do.