I installed drupal 7.34 with oracle database. Now i need to save user registration data to another non-drupal table. User authentication also need to do with these non-drupal database field. Is there any method to generate the per-existing set of users in non-drupal database as drupal users.
This looks similar to what happens when someone tries to access CiviCRM tables from Drupal when the CiviCRM tables exist in different database containers.
Are these tables in the same database container or just on the same database server?
You may want to look at How to use separate databases for Drupal tables?
It might also be worth looking at http://wiki.civicrm.org/confluence/display/CRMDOC44/Creating+a+Drupal+user+for+every+CiviCRM+contact
That gives both a manual process of generating Drupal users from a CSV export as well as the drush method.