instruction: what is the number of patients who are taking main type drug medication and have diagnoses of other fingers amputation status?
response: SELECT COUNT(DISTINCT demographic.subject_id) FROM demographic INNER JOIN diagnoses ON demographic.hadm_id = diagnoses.hadm_id INNER JOIN prescriptions ON demographic.hadm_id = prescriptions.hadm_id WHERE diagnoses.short_title = "Status amput oth fingers" AND prescriptions.drug_type = "MAIN"