Erase everything - Database schema

If you wish to format your schema, then follow these steps->

1) Run the following query->

SELECT 'DROP '||object_type||' '|| object_name||  DECODE(object_type,'TABLE',' CASCADE CONSTRAINTS;',';') FROM user_objects ORDER BY object_id DESC;

2) Copy and paste the output from above query and execute it.

3) Execute this -> PURGE RECYCLEBIN;