ราคาของยา dexamethasone คืออะไร?ไม่จำเป็นต้องใช้ตารางทั้งหมด
what are the prices of the drug dexamethasone?It is not neccessary to use all the tables.
 procedures_icd:  row_id [ number]  subject_id [ number]  hadm_id [ number]  icd9_code [ text]  charttime [ time] 
SELECT DISTINCT cost.cost FROM cost WHERE cost.event_type = 'prescriptions' AND cost.event_id IN (SELECT prescriptions.row_id FROM prescriptions WHERE prescriptions.drug = 'dexamethasone')