คำนวณจำนวนผู้ป่วยที่ได้รับยาระงับประสาท - ลอราซีแพม จนถึงปี 2104 ไม่จำเป็นต้องใช้ตารางทั้งหมด
calculate the number of patients who had received a sedative - lorazepam procedure until 2104.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 COUNT(DISTINCT patient.uniquepid) FROM patient WHERE patient.patientunitstayid IN (SELECT treatment.patientunitstayid FROM treatment WHERE treatment.treatmentname = 'sedative - lorazepam' AND STRFTIME('%y', treatment.treatmenttime) <= '2104')