มีผู้ป่วยกี่รายที่ได้รับการฉีดวัคซีนซึ่งต้องดำเนินการสองครั้งในปีที่แล้ว?ไม่จำเป็นต้องใช้ตารางทั้งหมด
how many patients have received a vaccination nec procedure two times the previous year?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 COUNT(DISTINCT t1.subject_id) FROM (SELECT admissions.subject_id, COUNT(*) AS c1 FROM procedures_icd JOIN admissions ON procedures_icd.hadm_id = admissions.hadm_id WHERE procedures_icd.icd9_code = (SELECT d_icd_procedures.icd9_code FROM d_icd_procedures WHERE d_icd_procedures.short_title = 'vaccination nec') AND DATETIME(procedures_icd.charttime, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-1 year') GROUP BY admissions.subject_id) AS t1 WHERE t1.c1 = 2