ในบรรดาผู้ป่วยที่เปลี่ยนลิ้นหัวใจเอออร์ติคแบบเปิดและการปลูกถ่ายเนื้อเยื่อ มีกี่รายที่เป็นเชื้อสายผิวขาว?ไม่จำเป็นต้องใช้ตารางทั้งหมด
among patients who had open and other replacement of aortic valve with tissue graft, how many of them belonged to white ethnic origin?It is not neccessary to use all the tables.
 demographic:  subject_id [ text]  hadm_id [ text]  name [ text]  marital_status [ text]  age [ text]  dob [ text]  gender [ text]  language [ text]  religion [ text]  admission_type [ text]  days_stay [ text]  insurance [ text]  ethnicity [ text]  expire_flag [ text]  admission_location [ text]  discharge_location [ text]  diagnosis [ text]  dod [ text]  dob_year [ text]  dod_year [ text]  admittime [ text]  dischtime [ text]  admityear [ text] 
SELECT COUNT(DISTINCT demographic.subject_id) FROM demographic INNER JOIN procedures ON demographic.hadm_id = procedures.hadm_id WHERE demographic.ethnicity = "WHITE" AND procedures.long_title = "Open and other replacement of aortic valve with tissue graft"