ขอทราบจำนวนคนไข้ที่มีผลตรวจแลปไฮยาลินและเกิดก่อนปี 2121 ค่ะ ไม่จำเป็นต้องใช้ทุกโต๊ะ
give me the number of patients who had hyaline casts lab test and were born before 2121.It is not neccessary to use all the tables.
 diagnoses:  subject_id [ text]  hadm_id [ text]  icd9_code [ text]  short_title [ text]  long_title [ text] 
SELECT COUNT(DISTINCT demographic.subject_id) FROM demographic INNER JOIN lab ON demographic.hadm_id = lab.hadm_id WHERE demographic.dob_year < "2121" AND lab.label = "Hyaline Casts"