instruction: during their last hospital visit, what was the daily maximum weight of patient 22315?
response: SELECT MAX(chartevents.valuenum) FROM chartevents WHERE chartevents.icustay_id IN (SELECT icustays.icustay_id FROM icustays WHERE icustays.hadm_id IN (SELECT admissions.hadm_id FROM admissions WHERE admissions.subject_id = 22315 AND NOT admissions.dischtime IS NULL ORDER BY admissions.admittime DESC LIMIT 1)) AND chartevents.itemid IN (SELECT d_items.itemid FROM d_items WHERE d_items.label = 'admit wt' AND d_items.linksto = 'chartevents') GROUP BY STRFTIME('%y-%m-%d', chartevents.charttime)