อะไรคือความแตกต่างในด้านน้ำหนักของผู้ป่วย 2518 วัดที่ 2105-12-30 090000 เทียบกับค่าที่วัดที่ 2105-12-29 210000 ไม่จำเป็นต้องใช้ตารางทั้งหมด
what was the difference in the weight of patient 2518 measured at 2105-12-30 090000 compared to the value measured at 2105-12-29 210000.It is not neccessary to use all the tables.
 outputevents:  row_id [ number]  subject_id [ number]  hadm_id [ number]  icustay_id [ number]  charttime [ time]  itemid [ number]  value [ number] 
SELECT (SELECT 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 = 2518)) AND chartevents.itemid IN (SELECT d_items.itemid FROM d_items WHERE d_items.label = 'admit wt' AND d_items.linksto = 'chartevents') AND chartevents.charttime = '2105-12-30 09:00:00') - (SELECT 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 = 2518)) AND chartevents.itemid IN (SELECT d_items.itemid FROM d_items WHERE d_items.label = 'admit wt' AND d_items.linksto = 'chartevents') AND chartevents.charttime = '2105-12-29 21:00:00')