แจ้งชื่อและอายุของคนไข้ด้วย ID คนไข้ 81254 ไม่จำเป็นต้องใช้ทุกโต๊ะ
Let me know the name and age of the patient with patient id 81254.It is not neccessary to use all the tables.
 lab:  subject_id [ text]  hadm_id [ text]  itemid [ text]  charttime [ text]  flag [ text]  value_unit [ text]  label [ text]  fluid [ text] 
SELECT demographic.name, demographic.age FROM demographic WHERE demographic.subject_id = "81254"