Oracle DB what is the difference between ALL, USER and DBA Objects?
USER_OBJECTS are your objects, i.e. the objects where the current user is the owner
ALL_OBJECTS are all objects which you can access. These are of course your own objects from above plus objects from other schemas where access is granted to you.
DBA_OBJECTS are all objects in the database. As a DBA you have access to all objects, thus ALL_OBJECTS and DBA_OBJECTS should be the same if you are connected as DBA.


If you want to remove all objects from a user then the best command would be DROP USER xyz CASCADE;

Do not delete anything from XXX_OBJECTS view. Use DROP ... commands to removed those objects.