postgresql7.3 select round(date_part('epoch', now() - creation_datetime)) as elapsed_time from as_sessions where session_id = :session_id select s.section_id, cr.title, cr.description, s.instructions, m.max_time_to_complete, s.display_type_id, s.num_items, round(date_part('epoch', now() - d.creation_datetime)) as elapsed_time from cr_revisions cr, as_sections s, as_assessment_section_map m, as_section_data d where cr.revision_id = s.section_id and s.section_id = :section_id and m.section_id = s.section_id and m.assessment_id = :assessment_rev_id and d.session_id = :session_id and d.section_id = m.section_id