Question: List the violation type ID of business with business ID from 30 to 50 and located at 747 IRVING St, San Francisco.
SQL: SELECT DISTINCT T1.violation_type_id FROM violations AS T1 INNER JOIN businesses AS T2 ON T1.business_id = T2.business_id WHERE T2.business_id BETWEEN 30 AND 50 AND T2.address = '747 IRVING St' AND T2.city = 'San Francisco'