postgresql7.1
select response_id, case when initial_response_id is NULL then 'T' else 'F' end as original_p, coalesce(initial_response_id,response_id) as initial_response, creation_date
from survey_responses, acs_objects
where response_id = object_id
and creation_user = :user_id
and survey_id=:survey_id
order by creation_date desc