what's the total amount of output that patient 18457 has had on 10/04/2102?
select sum(outputevents.value) from outputevents where outputevents.icustay_id in ( select icustays.icustay_id from icustays where icustays.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 18457 ) ) and strftime('%y-%m-%d',outputevents.charttime) = '2102-10-04'