Revoke All Privileges from User/Role/Public in Oracle

Revoke All Privileges from User/Role/Public in Oracle

REVOKE ALL FROM {user, | role, |PUBLIC}
   
example: REVOKE ALL FROM SYSTEM;   

REVOKE ALL ON employee FROM SCOTT;

Find Roles Granted to PUBLIC

select * from dba_role_privs where GRANTEE = 'PUBLIC';

Find DBA Roles Granted to Users

select GRANTEE, ADMIN_OPTION, DEFAULT_ROLE 
from dba_role_privs 
where GRANTED_ROLE = 'DBA';