นับจำนวนผู้ป่วยที่ได้รับยาโพลีเอทิลีนไกลคอล 3350 17 กรัม pwpk ทางปากภายในเดือนเดียวกันหลังจากขั้นตอนการให้อิเล็กโทรไลต์ - แคลเซียมจนกระทั่ง 4 ปีที่แล้ว ไม่จำเป็นต้องใช้ตารางทั้งหมด
count the number of patients who were prescribed polyethylene glycol 3350 17 gram oral pwpk within the same month after their procedure of electrolyte administration - calcium until 4 years ago.It is not neccessary to use all the tables.
 patient:  uniquepid [ text]  patienthealthsystemstayid [ number]  patientunitstayid [ number]  gender [ text]  age [ text]  ethnicity [ text]  hospitalid [ number]  wardid [ number]  admissionheight [ number]  admissionweight [ number]  dischargeweight [ number]  hospitaladmittime [ time]  hospitaladmitsource [ text]  unitadmittime [ time]  unitdischargetime [ time]  hospitaldischargetime [ time]  hospitaldischargestatus [ text] 
SELECT COUNT(DISTINCT t1.uniquepid) FROM (SELECT patient.uniquepid, treatment.treatmenttime FROM treatment JOIN patient ON treatment.patientunitstayid = patient.patientunitstayid WHERE treatment.treatmentname = 'electrolyte administration - calcium' AND DATETIME(treatment.treatmenttime) <= DATETIME(CURRENT_TIME(), '-4 year')) AS t1 JOIN (SELECT patient.uniquepid, medication.drugstarttime FROM medication JOIN patient ON medication.patientunitstayid = patient.patientunitstayid WHERE medication.drugname = 'polyethylene glycol 3350 17 gram oral pwpk' AND DATETIME(medication.drugstarttime) <= DATETIME(CURRENT_TIME(), '-4 year')) AS t2 WHERE t1.treatmenttime < t2.drugstarttime AND DATETIME(t1.treatmenttime, 'start of month') = DATETIME(t2.drugstarttime, 'start of month')