จำนวนผู้ป่วยที่อยู่ใน careunit micu ในปี 2104 ไม่จำเป็นต้องใช้ตารางทั้งหมด
how many patients were in careunit micu in 2104.It is not neccessary to use all the tables.
 prescriptions:  row_id [ number]  subject_id [ number]  hadm_id [ number]  startdate [ time]  enddate [ time]  drug [ text]  dose_val_rx [ text]  dose_unit_rx [ text]  route [ text] 
SELECT COUNT(DISTINCT admissions.subject_id) FROM admissions WHERE admissions.hadm_id IN (SELECT transfers.hadm_id FROM transfers WHERE transfers.careunit = 'micu' AND STRFTIME('%y', transfers.intime) = '2104')