Remove duplicate data in revision tables in database Possible Duplicate:
  How to disable the revision feature completely?  




How can I disable duplicate data in database. one example is this image:
You can't unfortunately.

The concept of storing field data and revision data in two different tables is hard coded into entities at the very lowest level.

If you want to change this behaviour you're looking at a major rewrite of the entity and field systems, and I very much doubt there's any way to do it without hacking a fair few of the core files.

The best thing to do is just accept that this is how Drupal stores its data and try to work with it rather than try to get around it.