calculate patient 15119's length of stay in the icu for the last time.
select strftime('%j',icustays.outtime) - strftime('%j',icustays.intime) from icustays where icustays.hadm_id in ( select admissions.hadm_id from admissions where admissions.subject_id = 15119 ) and icustays.outtime is not null order by icustays.intime desc limit 1