บอกฉันหน่อยว่าการทดสอบตัวอย่างที่พบบ่อยที่สุดสามอันดับแรกในปีนี้คืออะไร?ไม่จำเป็นต้องใช้ตารางทั้งหมด
tell me what the top three most common specimen tests were this year?It is not neccessary to use all the tables.
 chartevents:  row_id [ number]  subject_id [ number]  hadm_id [ number]  icustay_id [ number]  itemid [ number]  charttime [ time]  valuenum [ number]  valueuom [ text] 
SELECT t1.spec_type_desc FROM (SELECT microbiologyevents.spec_type_desc, DENSE_RANK() OVER (ORDER BY COUNT(*) DESC) AS c1 FROM microbiologyevents WHERE DATETIME(microbiologyevents.charttime, 'start of year') = DATETIME(CURRENT_TIME(), 'start of year', '-0 year') GROUP BY microbiologyevents.spec_type_desc) AS t1 WHERE t1.c1 <= 3