อะไรคือความแตกต่างในค่า hct ของผู้ป่วย 010-37499 ที่วัดที่ 2105-01-18 172300 เทียบกับค่าที่วัดที่ 2105-01-17 215100? ไม่จำเป็นต้องใช้ตารางทั้งหมด
what were the differences in hct values of patient 010-37499 measured at 2105-01-18 172300 compared to the value measured at 2105-01-17 215100?It is not neccessary to use all the tables.
 vitalperiodic:  vitalperiodicid [ number]  patientunitstayid [ number]  temperature [ number]  sao2 [ number]  heartrate [ number]  respiration [ number]  systemicsystolic [ number]  systemicdiastolic [ number]  systemicmean [ number]  observationtime [ time] 
SELECT (SELECT lab.labresult FROM lab WHERE lab.patientunitstayid IN (SELECT patient.patientunitstayid FROM patient WHERE patient.patienthealthsystemstayid IN (SELECT patient.patienthealthsystemstayid FROM patient WHERE patient.uniquepid = '010-37499')) AND lab.labname = 'hct' AND lab.labresulttime = '2105-01-18 17:23:00') - (SELECT lab.labresult FROM lab WHERE lab.patientunitstayid IN (SELECT patient.patientunitstayid FROM patient WHERE patient.patienthealthsystemstayid IN (SELECT patient.patienthealthsystemstayid FROM patient WHERE patient.uniquepid = '010-37499')) AND lab.labname = 'hct' AND lab.labresulttime = '2105-01-17 21:51:00')