อะไรคือห้าขั้นตอนที่พบบ่อยที่สุดในปี 2101?ไม่จำเป็นต้องใช้ตารางทั้งหมด
what were the five procedures that were the most frequent in 2101?It is not neccessary to use all the tables.
 labevents:  row_id [ number]  subject_id [ number]  hadm_id [ number]  itemid [ number]  charttime [ time]  valuenum [ number]  valueuom [ text] 
SELECT d_icd_procedures.short_title FROM d_icd_procedures WHERE d_icd_procedures.icd9_code IN (SELECT t1.icd9_code FROM (SELECT procedures_icd.icd9_code, DENSE_RANK() OVER (ORDER BY COUNT(*) DESC) AS c1 FROM procedures_icd WHERE STRFTIME('%y', procedures_icd.charttime) = '2101' GROUP BY procedures_icd.icd9_code) AS t1 WHERE t1.c1 <= 5)