Check Database User privileges and Roles

You can check the particular user privileges and roles (system and object) by the use of following script.
This script gives all the privileges and roles granted to a particular user by setting usercheck environment.

set lines 110 pages 1000 ver off
col role for a16
col pv for a75 hea 'PRIVILEGE OR ROLE'
bre on role on type skip 1

define usercheck = 'USERNAME'

select grantee, 'ROL' type, granted_role pv 
from dba_role_privs where grantee = '&usercheck' union 
select grantee, 'PRV' type, privilege pv 
from dba_sys_privs where grantee = '&usercheck' union
select grantee, 'OBJ' type, 
max(decode(privilege,'WRITE','WRITE,'))||max(decode(privilege,'READ','READ'))||
max(decode(privilege,'EXECUTE','EXECUTE'))||max(decode(privilege,'SELECT','SELECT'))||
max(decode(privilege,'DELETE',',DELETE'))||max(decode(privilege,'UPDATE',',UPDATE'))||
max(decode(privilege,'INSERT',',INSERT'))||' ON '||object_type||' "'||a.owner||'.'||table_name||'"' pv 
from dba_tab_privs a, dba_objects b 
where a.owner=b.owner and a.table_name = b.object_name and a.grantee='&usercheck'
group by a.owner,table_name,object_type,grantee union
select username grantee, '---' type, 'empty user ---' pv from dba_users 
where not username in (select distinct grantee from dba_role_privs) and
not username in (select distinct grantee from dba_sys_privs) and 
not username in (select distinct grantee from dba_tab_privs) and username like '%&usercheck%'
group by username
order by grantee, type, pv;