ขอทราบจำนวนคนไข้ประเภทเข้าฉุกเฉินและวินิจฉัยรหัส icd9 เป็น 1,550 ได้หรือไม่ ไม่จำเป็นต้องใช้ทุกตาราง
give me the number of patients whose admission type is emergency and diagnoses icd9 code is 1550?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 diagnoses ON demographic.hadm_id = diagnoses.hadm_id WHERE demographic.admission_type = "EMERGENCY" AND diagnoses.icd9_code = "1550"