If you didn't know how you can easily select the current APEX version or the current APEX database user APEX_xxxxx. You can use these selects:
-- Select current APEX user over all_users/dba_users
select max(u1.username) as current_apex_user
from all_users u1
where u1.username like 'APEX%'
and REGEXP_LIKE (substr(u1.username,'6',1), '^[0-9]*$');
-- CURRENT_APEX_USER
---------------------
-- APEX_040000
-- Select current version over dba_registry
select comp_name, version from dba_registry
where comp_name = 'Oracle Application Express';
-- COMP_NAME VERSION_NO
-------------------------------------------
-- Oracle Application Express 4.0.1.00.03
-- Select current version over apex_release
select * from apex_release;
-- VERSION_NO API_COMPATIBILITY PATCH_APPLIED
----------------------------------------------------
-- 4.0.1.00.03 2010.05.13 null
